Hayabusa 2021 Symposium Schedule (Online Meeting)version. 20211111(8th ISAS Symposium of the Solar System Materials )16th(Tue)‐17th(Wed) of November 2021
Oral : Zoom Meeting (10+5 min for Invited and normal talks, 7+3 min for 10 min short talks)
Poster : Zoom Meeting Breakout Rooms
Non‐real time discussion : Slack
Day‐1 (Nov 16th) : Oral Session
JST

GMT

EST

PST

No.

(‐1day) (‐1day)

Title
Session‐0 : Opening session:

Author/Presenter

InvitedT. Okada

09:45

00:45

19:45

16:45

S0‐1

Opening and Logistics

Tatsuaki Okada

09:50

00:50

19:50

16:50

S0‐2

Status of JAXA Curation activity and future plan

Tomohiro Usui

Session‐1: Ryugu sample : S. Tachibana, T. Usui
10:00

01:00

20:00

17:00

S1‐1

An overview of initial descriptions for samples returned from C‐type asteroid Ryugu

Toru Yada

Invited

10:15

01:15

20:15

17:15

S1‐2

First NIR hyperspectral imaging of Hayabusa2 returned samples by the MicrOmega microscope within the ISAS Curation Facility

Cedric Pilorget

Invited

10:30

01:30

20:30

17:30

S1‐3

Initial analysis of Hayabusa2 returned samples from asteroid (162173) Ryugu

Shogo Tachibana

10:45

01:45

20:45

17:45

S1‐4

Progress of chemical characterization of asteroid Ryugu samples

Hisayoshi Yurimoto

Invited

11:00

02:00

21:00

18:00

S1‐5

Initial analysis of “stone” size Ryugu samples: current status

Tomoki Nakamura

Invited

11:15

02:15

21:15

18:15

S1‐6

Mineralogy and surface modification of small grains recovered from the asteroid 162173 Ryugu

Takaaki Noguchi

Invited

11:30

02:30

21:30

18:30

S1‐7

Initial Analysis of Volatile Components in the Hayabusa2 Samples

Ryuji Okazaki

Invited

11:45

02:45

21:45

18:45

S1‐8

An initial look at the distributions and compositions of organic macromolecules in the asteroid Ryugu samples

Hikaru Yabuta

Invited

12:00

03:00

22:00

19:00

S1‐9

Soluble Organic Matter (SOM) analysis of the Hayabusa2 samples: The first results

Hiroshi Naraoka

Invited

12:15

03:15

22:15

19:15

<Lunch break>

All

13:30

04:30

23:30

20:30

S2‐1

A first look at the interior and exterior of Ryugu preserved in samples collected by Hayabusa2

Eizo Nakamura

Invited

13:45

04:45

23:45

20:45

S2‐2

The C‐type asteroid Ryugu: A first detailed look by Phase2 Curation Kochi (Ph2K)

Motoo Ito

Invited

14:00

05:00

00:00

21:00

S2‐3

JAXA Detailed Description ‐Variation of surface characteristics of Ryugu returned samples‐

Aiko Nakato[Group Photo‐1]

Sessions‐2 : Ryugu Sample (Cont.) : R. Brunetto, A. Nakato

14:15

05:15

00:15

21:15

S2‐4

Overview of the features of returned samples from the C‐type asteroid 162173 Ryugu based on optical microscope observations and their weights

Akiko Miyazaki

10 min

14:25

05:25

00:25

21:25

S2‐5

Initial description of Ryugu returned samples: characteristics of individual grains by FT‐IR analysis

Kentaro Hatakeda

10 min

14:35

05:35

00:35

21:35

S2‐6

MicrOmega detections of C‐rich phases in Ryugu returned samples within the Hayabusa2 JAXA Extraterrestrial Curation Center

Jean‐Pierre Bibring

14:50

05:50

00:50

21:50

S2‐7

MicrOmega detections of carbonates in Ryugu returned samples within the Hayabusa 2 JAXA Extraterrestrial Curation Center

Damien Loizeau

10 min

15:00

06:00

01:00

22:00

S2‐8

The 2.7μm OH band in different grains of Ryugu from the two collection sites, as seen by MicrOmega in the Hayabusa2 Curation Facility

Tania Le Pivert‐Jolivet

10 min

15:10

06:10

01:10

22:10

S2‐9

Microscale diversity of H, C, and N isotopes in asteroid Ryugu

Larry R. Nittler

15:25

06:25

01:25

22:25

S2‐10

Diversity of Insoluble Organic Matter at the Nanoscale in Asteroid Ryugu

Rhonda Stroud

15:40

06:40

01:40

22:40

S2‐11

Infrared transmission spectra of Ryugu particles and their unique adsorption behavior

Yoko Kebukawa

15:55

06:55

01:55

22:55

S2‐12

Thermal history of Ryugu based on Raman characterization of Hayabusa2 samples

Lydie Bonal

16:10

07:10

02:10

23:10

S2‐13

Elemental and isotopic compositions of organic grains from asteroid Ryugu

Laurent Remusat

16:25

07:25

02:25

23:25

16:40

07:40

02:40

23:40

S3‐1

Exposure Conditions of Samples Collected on Ryugu’s Two Touchdown Sites Determined by Cosmogenic Nuclides

Kunihiko Nishiizumi

16:55

07:55

02:55

23:55

S3‐2

Small grains from Ryugu: handling and analysis pipeline for Infrared Synchrotron Microspectroscopy

Stefano Rubino

17:10

08:10

03:10

00:10

S3‐3

Preliminary results from FTIR hyper‐spectral imaging campaign on Ryugu small grains and fragments.

Zelia Dionnet

17:25

08:25

03:25

00:25

S3‐4

Iron valence state and mineralogy in particles from asteroid Ryugu

Mathieu Roskosz

17:40

08:40

03:40

00:40

S3‐5

Three‐dimensional analysis of Ryugu sample particles using X‐ray nanotomography.

Akira Tsuchiyama

17:55

08:55

03:55

00:55

S3‐6

Surface morphologies and space weathering features of Ryugu samples

Toru Matsumoto

18:10

09:10

04:10

01:10

S3‐7

CNHOS contents with their isotopic compositions and preliminary organic profiles from the Hayabusa2 samples

Yoshinori Takano

18:25

09:25

04:25

01:25

S3‐8

Compound distribution determined by nanoLC‐Orbitrap MS

François‐Régis Orthous‐Daunay

18:40

09:40

04:40

01:40

S3‐9

Highest molecular diversity and structural complexity revealed with ultrahigh resolution mass spectrometry and nuclear magnetic resonance spectroscopy of Ryugu
Philippe Schmitt‐Kopplin´s samples

18:55

09:55

04:55

01:55

<Coffee Break>Sessions‐3 : Ryugu Sample (Cont.) : H. Sugahara, D. Yamamoto

Discussion on Ryugu sample

S. Tachibana (Lead)[Group Photo‐2]

AllHayabusa 2021 Symposium Schedule (Online Meeting)version. 20211111(8th ISAS Symposium of the Solar System Materials )16th(Tue)‐17th(Wed) of November 2021
Oral : Zoom Meeting (10+5 min for Invited and normal talks, 7+3 min for 10 min short talks)
Poster : Zoom Meeting Breakout Rooms
Non‐real time discussion : SlackDay‐2 (Nov 17th) : Oral Session
JST

GMT

EST

PST

No.

(‐1day) (‐1day)

Title

Author/Presenter

InvitedSession‐4 : Asteroid ‐ Meteorite Connection : K. Righter, T. Okada

09:30

00:30

19:30

16:30

S4‐1

The Winchcombe Meteorite: A Pristine Sample of the Outer Asteroid Belt

Ashley J King

09:45

00:45

19:45

16:45

S4‐2

Thermal History of Dehydrated CY Chondrites Reconstructed from their Fe‐sulfide Grains

Catherine Harrison

Invited

10:00

01:00

20:00

17:00

S4‐3

Hydrothermal history of (162173) Ryugu’s parent body inferred from remote‐sensing data

Eri Tatsumi

Invited

10:15

01:15

20:15

17:15

S4‐4

Multiband thermal radiometry and related laboratory studies, indicating possible origin and evolution of Ryugu.

Maximilian Hamm

Invited

10:30

01:30

20:30

17:30

S4‐5

Color Mapping of Asteroid Bennu

Daniella DellaGiustina

Invited

10:45

01:45

20:45

17:45

S4‐6

The Mineralogy and Organic Composition of Bennu as Observed by VNIR and TIR Spectroscopy

Victoria E. Hamilton

Invited

11:00

02:00

21:00

18:00

S4‐7

The Nature of Extraterrestrial Amino Acids in Carbonaceous Chondrites and Links to Their Parent Bodies

Daniel Patrick Glavin

Invited

11:15

02:15

21:15

18:15

S4‐8

Oxygen isotopes and water in bulk matrix of CM2 Murchison as an analog for Ryugu matrix

Aditya Patkar

S4‐9

11:30

02:30

21:30

18:30

11:45

02:45

21:45

18:45

Anomalous and ungrouped carbonaceous chondrites in the US Antarctic meteorite collection and their potential relevance to Ryugu and Bennu

Kevin Righter<Lunch break>

All

13:00

04:00

23:00

20:00

S5‐1

Volatiles in Chondrites and Achondrites

Maitrayee Bose

13:15

04:15

23:15

20:15

S5‐2

Space weathering of sulfides and silicate minerals from asteroid Itokawa

Laura Camila Chaves[Group Photo‐3]

Session-5 : Itokawa Sample and Meteorites : T. Ireland, T. Yada
Invited

13:30

04:30

23:30

20:30

S5‐3

Space weathering of iron sulfides on airless bodies

Toru Matsumoto

13:45

04:45

23:45

20:45

S5‐4

Extraterrestrial Non‐Protein Amino Acids Identified in Carbon‐Rich Particles Returned from Asteroid Itokawa

Eric Thomas Parker

Invited

14:00

05:00

00:00

21:00

S5‐5

NaCl in an Itokawa Particle: Terrestrial or Asteroidal?

Shaofan Che

14:15

05:15

00:15

21:15

S5‐6

Northwest Africa 5401 CV chondrite: Not oxidized, not reduced, maybe in between?

Timothy J. Fagan

14:30

05:30

00:30

21:30

S5‐7

Organics and iron speciation in CI chondrites : a combined STXM and TEM study

Corentin Le Guillou

14:45

05:45

00:45

21:45

S5‐8

Shocked regolith in asteroid 25143 Itokawa surface

Josep M. Trigo‐Rodriguez

15:00

06:00

01:00

22:00

S5‐9

Organic matter in Itokawa particles

Queenie Hoi Shan Chan

15:15

06:15

01:15

22:15

15:30

06:30

01:30

22:30

S6‐1

Hayabusa2 curation: from concept, design, development, to operations

Masanao Abe

15:45

06:45

01:45

22:45

S6‐2

Sample Analysis Plan for NASA’s OSIRIS‐REx Mission

Harold C. Connolly Jr.

Invited

16:00

07:00

02:00

23:00

S6‐3

Scientific importance of the sample analyses of Phobos regolith and the analytical protocols of returned samples by the MMX mission

Wataru Fujiya

Invited

16:15

07:15

02:15

23:15

S6‐4

What should we do with these Martian rocks? A tale of MSR Sample Science and Curation

Aurore Hutzler

Invited

16:30

07:30

02:30

23:30

S6‐5

A New Laboratory Facility in the Era of Sample Return: the Sample Analysis Laboratory (SAL) at DLR Berlin

Enrica Bonato

Invited<Coffee Break>Session‐6 : Sample Return & Space Missions: M. Abe, J. Helbert

16:45

07:45

02:45

23:45

S6‐6

Milani CubeSat for ESA Hera mission

Tomas Kohout

17:00

08:00

03:00

00:00

S6‐7

The young basalts on the Moon: Pb–Pb isochron dating in Chang’e‐5 Basalt CE5C0000YJYX03501GP

Dunyi Liu

17:15

<Coffee break>Session-7 : Summary and Ending : T. Usui

17:30

08:30

03:30

00:30

18:00

09:00

04:00

01:00

S7‐1

Wrap‐up and Summary

Tomohiro Usui (Lead)

AdjournAll[Group Photo‐4]

InvitedHayabusa 2021 Symposium Schedule (Online Meeting)(8th ISAS Symposium of the Solar System Materials )16th(Tue)‐17th(Wed) of November 2021

version. 20211111

Oral : Zoom Meeting (10+5 min for Invited and normal talks, 7+3 min for 10 min short talks)
Poster : Zoom Meeting Breakout Rooms
Non‐real time discussion : Slack
Day‐1 (Nov 16th) : Poster Session
JST

GMT

EST

PST

No.

Title
Poster Session and chat (2 hours)

19:15

10:15

05:15

02:15

:

Author/Presenter

R. Fukai, T. Hayashi

P‐1

The fundamental deformation of cosmic bodies not depending of their sizes and compositions(from asteroids to Universe)

Gennady Gregory Kochemasov

P‐2

Exogenous copper sulfide in a returned grain from asteroid Itokawa

Katherine D Burgess

P‐3

A Series of Recent Falls of Carbonaceous Chondrites ‐ Perfect Analogues for Returned Hayabusa 2 and Osiris Rex Asteroidal Materials

Viktor H Hoffmann

P‐4

Heated Synthetic Murchison Reflectance Spectra

Sahejpal Sidhu

P‐5

Status of the Curatorial Database System for the Ryugu Samples

Masahiro Nishimura

P‐6

Methodology of MicrOmega data acquisition/processing in initial description of Ryugu returned samples

Kasumi Yogata

P‐7Comparison of ion‐ and laser‐weathered spectra of olivines and pyroxenesKateřina Chrbolková

P‐8

Solid Materials of Mineral and Rock on the Solar System: X‐ray Unit and Mixed Status

Yasunori Miura

P‐9Model of Material Characteristics of Carbonaceous Meteorites from Texture of Carbon‐Bearing Grains

Yasunori Miura

P‐10

Neural network for classification of asteroid spectraDavid Korda

P‐11

Assessment of organic, inorganic, and microbial contamination in the facilities of the Extraterrestrial Sample Curation Center of JAXA

Yuya Hitomi

InvitedAn overview of initial descriptions for samples returned from C-type asteroid Ryugu.
T. Yada1, M. Abe1, A. Nakato1, K. Yogata1, A. Miyazaki1, K. Kumagai2, K. Hatakeda2, T. Okada1, M. Nishimura1,
S. Furuya1,3, M. Yoshitake1,4, A. Iwamae2,5, Y. Hitomi2, H. Soejima2, K. Nagashima1, R. Sawada2, L. Riu1,6, L. Lourit6,
C. Pilorget6, V. Hamm6, D. Loizeau6, R. Brunetto6, J.-P. Bibring6, Y. Cho3, K. Yumoto3, Y. Yabe3, S. Mori3, S. Sugita3,
S. Tachibana1,3, H. Sawada1, K. Sakamoto1, T. Hayashi1, D. Yamamoto1, R. Fukai1, H. Sugahara1, H. Yurimoto7, T. Usui1,
S. Watanabe8, Y. Tsuda1
1Inst. Space Astronaut. Sci., Japan Aerosp. Explor. Agency (JAXA), Kanagawa 252-5210, Japan(yada@planeta.sci.isas.jaxa.jp), 2Marine Works Japan Ltd., Yokosuka 237-0063, Japan, 3UTOPS, Grad. Sch. Sci., Univ.
Tokyo, Tokyo 113-0033, Japan, 4Japan Patent Office, Chiyoda-ku, Tokyo 100-8915, Japan, 5Toyo Univ., Bunkyo-ku, Tokyo
112-8606, Japan, 6Institut d'Astrophysique Spatiale, Université Paris-Saclay, CNRS, 91400 Orsay, France, 7Dept. Earth Planet.
Sci., Grad. Sch. Sci., Hokkaido Univ., Hokkaido 060-0808, Japan, 8Dept Earth Planet. Sci., Grad. Sch. Sci., Nagoya Univ.,
Nagoya 464-8601, Japan.
Introduction: Hayaubsa2 spacecraft operated by JAXA explored a near-Earth asteroid 162173 Ryugu from Jun 2017 to Nov
2019 [1]. During the exploration, the spacecraft accomplished touchdown sampling on the asteroid’s surface in Feb and Jul of2019 [2]. The samples recovered by the first touchdown were stored in the Chamber A of a sample catcher and those by thesecond one were in the Chamber C [2]. The sample catcher was sealed in a sample container, which was set in a reentry capsuleof the spacecraft, and the capsule was returned to the Earth, the Woomera Prohibited Area in South Australia, on 6 Dec 2020 [2,3].
Extraction Procedures for Ryugu samples: As the container was transported from Australia to Japan by air and arrived atcleanrooms of the Extraterrestrial Sample Curation Center (ESCuC), it was disassembled to remove unnecessary parts andcleaned on its surface in the cleanrooms and introduced into the clean chamber (CC) 3-1 to be evacuated to high vacuum [2, 3].
In the static vacuum condition, the container was opened and the sample catcher was extracted from the container. The catcher
was transported to the next chamber, CC3-2, and a lid of the Chamber A of the catcher was removed from the catcher and a few
mm-size particles were recovered from the Chamber A to a quartz glass container in vacuo. Then the catcher with rest of samples
was transported to the next chamber, CC3-3, then the catcher handling environment have changed from vacuum to purified
nitrogen condition. Hereafter, all the extraction works and initial descriptions have been done in this purified nitrogen conditionin the clean chambers. The catcher was firstly measured with a balance equipped in the chamber CC4-2 to confirm the bulk
samples’ weight in it, to be 5.4 grams [3]. Then it was dismantled with catcher handling tools in the chamber CC4-1 to recoversamples from each chamber of the catcher to sapphire dishes of 23mm in diameter.
Initial descriptions for bulk and individual Ryugu samples: Each of the bulk samples in the dishes were observed andphotographed with a stereomicroscope equipped above the chamber CC4-2. Then they were also measured with the balance for
their bulk weights to be 3.2 grams and 2.0 grams from the from the Chamber A and C, respectively [4]. They were then analyzed
with a Fourier Transmission Infrared spectrometer (FT-IR) for their near infrared reflectance spectra in wavelength ranging from
2.0 to 4.0 µm [4]. They were also analyzed with a MicrOmega, infrared imager comparable to that onboard instrument of
MASCOT lander released from Hayabusa2 spacecraft, for obtaining overall and local infrared spectra in the bulk Ryugu samples[1, 5-7]. Finally, they were analyzed with an optical microscopic imaging through six filters (ul: 0.39 µm, b: 0.48µm, v: 0.55µm, Na: 0.59 µm, w: 0.70 µm, x: 0.85 µm), compatible with the ONC-T camera of Hayabusa2, onboard instrument of Hayabusa2[8]. After the series of initial descriptions for bulk Ryugu samples, individual particles have been handpicked from the bulk
samples to sapphire dishes for individual samples with a vacuum tweezer, and described in the same manner as the bulk samples
experienced [9-11]. The results of initial descriptions for bulk Ryugu samples are presented in [4]. Their small bulk densities
and dark visible and infrared spectral features indicates that obtained samples are representative of surface materials of Ryugu.
Together with absence of high temperature components like a chondrule and a Calcium-Aluminum rich Inclusion (CAI) andpresence of 2.7 µm absorption band in infrared spectra, which corresponds to hydroxyls (-OH) absorption implying abundantphyllosilicate, they are most similar to CI chondrites among known planetary materials.
Data archive and sample distributions: All the obtained data by the initial descriptions have been archived in Hayabusa2
sample data catalog [12]. This catalog will be in public soon as a reference of Announcement of Opportunity (AO) for Ryugu
samples, which will start in early 2022. Any researcher can apply for the AO, and Ryugu samples will be distributed to Principle
Investigators (PIs) of selected proposals in the middle of 2022.

References: [1] Tsuda Y. et al. (2020) Acta Astron. 171, 42-54. [2] Tachibana S. et al. (2021) LPS, XXXXXII, Abstract #1289.
[3] Yada T. et al. (2021) LPS, XXXXXII, Abstract #2008. [4] Yada T. et al., submitted to Nature Astron. [5] Pilorget C. et al.,submitted to Nature Astron. [6] Bibring J.-P. et al., this meeting. [7] Yogata K. et al., this meeting. [8] Sugita S. et al. (2020)
Science 364, eaaw0422. [9] Miyazaki A. et al., this meeting. [10] Hatakeda K. et al., this meeting. [11] Cho Y. et al., thismeeting. [12] Nishimura M. et al., this meeting.

First NIR hyperspectral imaging of Hayabusa2 returned samples by the MicrOmega microscope within the ISAS Curation Facility
1

Pilorget, C.; 2,3Okada, T.; 1Hamm, V.; 1Brunetto, R.; 2Yada, T.; 1Loizeau, D.; 2Riu, L.; 2,3Usui, T.; 4Moussi-Soffys,
A.; 2,5Hatakeda, K; 2Nakato, A.; 2Yogata, K.; 2,6Abe, M.; 1Aléon-Toppani, A.; 1Carter, J.; 1Chaigneau, M.; 1Crane, B.;1
Gondet, B.; 2,5Kumagai, K.; 1Langevin, Y.; 1Lantz, C.; 1Le Pivert-Jolivet, T.; 1Lequertier, G.; 1Lourit, L.; 2Miyazaki,
A.; 2Nishimura, M.; 1Poulet, F.; 7Arakawa, M.; 8Hirata, N.; 8Kitazato, K.; 2Nakazawa, S.; 9Namiki, N.; 2Saiki, T.;
3
Sugita, S.; 2,3Tachibana, S.; 2,6,10Tanaka, S.; 2,6Yoshikawa, M.; 2,6Tsuda, Y.; 11Watanabe, S.; 1Bibring, J.-P.
[1] Institut d'Astrophysique Spatiale, Université Paris-Saclay, CNRS, 91400 Orsay, France, [2] Institute of Space andAstronautical Science, Japan Aerospace Exploration Agency, Sagamihara 252-5210, Japan, [3] University of Tokyo,
Bunkyo, Tokyo 113-0033, Japan, [4] Centre National d'Etudes Spatiales, 18 Avenue E. Belin, 31401 Toulouse,
France, [5] Marine Works Japan, Ltd., Yokosuka 237-0063, Japan, [6] The Graduate University for Advanced Studies(SOKENDAI), Hayama 240-0193, Japan, [7] Kobe University, Kobe 657-8501, Japan, [8] The University of Aizu,
Aizu-Wakamatsu 965-8580, Japan, [9] National Astronomical Observatory of Japan, Mitaka 181-8588, Japan, [10]University of Tokyo, Kashiwa 277-8561, Japan, [11] Nagoya University, Nagoya 464-8601, Japan.
Introduction: On December 6, 2020, the Hayabusa2 mission successfully returned to Earth ~ 5.4 g of samples collected at the surface of the C-type asteroid Ryugu [1,2]. Its surface was first sampled on February 22, 2019, then on
July 11, 2019, close to a 15-meter large artificial crater, so as to possibly access sub-surface material [3]. The collected
samples are now kept at the Extraterrestrial Samples Curation Center of JAXA at ISAS in Sagamihara, Japan, for a
first round of preliminary analyses, with the objective of characterizing in a non-destructive manner both the bulk
samples and a few hundreds of grains extracted from them [4]. In particular, the goal is 1) to support their further
detailed characterization by the international Initial Analysis Teams, and 2) to build a catalogue of the grains, accessible to the international community through AO selection, starting mid-2022.
Methods: The preliminary characterization of these samples is being conducted with a visible microscope withfive color filters, a FTIR spectrometer operating in the 1-4 µm range, and MicrOmega, a hyperspectral NIR microscope
developed at Institut d'Astrophysique Spatiale (Université Paris-Saclay/CNRS, Orsay, France), operating in the nearinfrared range (0.99-3.65 µm) [5]. This is the first time that preliminary analyses of returned extraterrestrial samples
include a characterization by a NIR hyperspectral microscope.
Results: Preliminary outcomes of the analyses performed with MicrOmega will be presented. In particular, therepresentativity of the samples collected by the Hayabusa2 spacecraft will be addressed through the comparison of
the spectra obtained by MicrOmega and of the NIRS3 remote sensing IR spectrometer [6] which performed a spectral
characterization (1.8-3.2 µm) of Ryugu's surface, including the sites of the samples' collection [7,8].
At a global scale, all bulks exhibit similar features, with a dominant OH- 2.7 µm component and a 3.3 – 3.5 µm
band centered around 3.4 µm. Their variation at different spatial scales and significance will be presented. Specificsignatures, detected in grains typically present in <1% of the pixels, but of high relevance regarding the processes
determining Ryugu formation and evolution, will also be presented and discussed.
References: [1] Binzel R. P. et al. (2002), Physical Properties of Near-Earth Objects. pp. 255-271, [2] Vilas F.
(2008) The Astronomical Journal 135 (4), 1101-1105, [3] Morota et al. (2020) Science 368, Issue 6491, pp. 654-659,[4] Yada T. et al., Nature Astronomy, submitted, [5] Bibring J.-P. et al. (2017) Astrobiology 17, Issue 6-7, pp.621626, [6] Iwata T. et al. (2017) Space Science Reviews 208 (1-4), 317-337, [7] Kitazato K. et al. (2019) Science 364(6437), 272-275, [8] Kitazato K. et al. (2020) Nature Astronomy, Volume 5, p. 246-250.

Initial analysis of Hayabusa2 returned samples from asteroid (162173) Ryugu
Shogo Tachibana1,2, Hisayoshi Yurimoto3, Tomoki Nakamura4, Takaaki Noguchi5,6, Ryuji Okazaki6, Hikaru Yabuta7, Hiroshi
Naraoka6, Kanako Sakamoto2, Sei-ichiro Watanabe8, Yuichi Tsuda2, and the Hayabusa2 Initial Analysis team1
Univ. Tokyo, 2ISAS, JAXA, 3Hokkaido Univ, 4Tohoku Univ., 5Kyushu Univ., 6Kyoto Univ., 7Hiroshima Univ., 8Nagoya Univ.
The JAXA’s Hayabusa2 spacecraft explored C-type near-Earth asteroid (162173) Ryugu from June 2018 to November 2019,
during which two touchdown operations were made to collect surface and subsurface samples. The Hayabusa2 delivered its
reentry capsule on December 6, 2020 to Woomera, South Australia [1]. The sample container inside the reentry capsule was
opened in the clean chamber system dedicated to Ryugu samples at ISAS, JAXA. Dark particles were found in both chambers
A and C, which were used for the storage of the samples collected at the first and second touchdown, respectively. The total
amount of the samples exceeds 5 g, which is much larger than the minimum requirement of 0.1 g [2]. Many millimeter-sizedparticles were present with fine powdery materials, and centimeter-sized grains, close to the maximum obtainable size [3],were found in the chamber C. The color, morphology, and spectroscopic features of the grains indicates that they well
represent the surface materials of Ryugu.
The initial analysis of a fraction of returned samples, led by the Hayabusa2 project, has begun in June 2021 after the
6-month sample description at the ISAS curation facility without exposure to the air. The initial analysis aims at maximizing
the scientific achievement of the project with answering important fundamental questions such as what materials Ryugu
consists of, how Ryugu evolved from its formation to the present, and how similar or different Ryugu samples are to the
known meteorites. The findings from Ryugu samples are expected to invoke cosmochemical discussion on the origin andevolution of the Solar System architecture such as the isotopic dichotomy in the early Solar System, the delivery of water andorganics to the inner Solar System, and the asteroid-comet continuum. The initial analysis also aims at providing the groundtruth for the remote sensing data obtained by the Hayabusa2 spacecraft.
The initial analysis team consists of six sub-teams for 1) chemistry (elements and isotopes) (Lead: Hisayoshi
Yurimoto, Hokkaido University), 2) petrology and mineralogy of coarse grains (mm-sized grains [stone]) (Lead: Tomoki
Nakamura, Tohoku University), 3) petrology and mineralogy of fine grains (<100 μm-sized grains [sand]) (Lead: Takaaki
Noguchi, Kyoto University/Kyushu University), 4) volatiles (Lead: Ryuji Okazaki, Kyushu University), 5) insoluble organic
matter (macromolecular organics) (Lead: Hikaru Yabuta, Hiroshima University), and 6) soluble organic matter (organic
molecules) (Lead: Hiroshi Naraoka, Kyushu University). The total number of teams members is nearly 300 from fourteen
countries. The initial analysis will continue for 12 months. The data obtained during the initial analysis will be archived in the
JAXA curatorial sample database to prove the potential of the samples to the community.
Three hundred milligrams of Ryugu samples (6 % of the total samples by mass) have been allocated from JAXA tothe initial analysis team; Twenty two grains, which were individually photographed, weighed, and spectroscopically examinedin the clean chamber system, and ten aggregate samples that mainly consist of particles smaller than 1 mm in diameter (Table
1).
Table 1. Samples allocated to the Hayabusa2 initial analysis team.
Individual grains
Individual grains
Aggregates
Aggregates(Chamber A)(Chamber C)(Chamber A)(Chamber C)
A0026 3.9 mg
C0002 93.5 mg
A0104 0.3 mg
C0105 0.4 mg
A0040 3.0 mg
C0023 5.0 mg
A0105 4.0 mg
C0106 4.0 mg
A0055 5.9 mg
C0025 5.6 mg
A0106 38.4 mg
C0107 38.8 mg
A0058 3.3 mg
C0033 2.4 mg
A0107 31.0 mg
C0108 33.0 mg
A0063 3.8 mg
C0040 4.9 mg
A0108 3.5 mg
C0109 3.7 mg
A0064 6.7 mg
C0046 2.6 mg
A0067 3.6 mg
C0055 0.8 mg
A0080 1.4 mg
C0057 0.9 mg
A0086 0.9 mg
C0061 1.3 mg
A0089 1.0 mg
C0076 4.7 mg
A0094 1.8 mg
C0103 1.5 mg

The allocated samples have been individually investigated by each sub-team or by collaboration of multiple sub-teams. The
C0002 grain from the chamber C is the third largest particle (~9 x 5 x 4 mm) among all the returned particles (Table 1). Thisgrain has been analyzed by all six sub-teams.
In this presentation we discuss the goals and overall activities of the initial analysis of Ryugu samples. Preliminary
results of elemental and isotopic analyses, mineralogical and petrological observation, and analyses of volatiles and organic
components will be presented from each sub team at the meeting [e.g., 4–22].
References[1] Tachibana S. et al. (2021) 51st LPSC, Abstract #1289. [2] Tachibana S. et al. (2014) Geochem. J. 48, 571–587. [3] Sawada
H. et al. (2017) Space Sci. Rev. 208, 81–106. [4] The Hayabusa2-initial-analysis chemistry team et al. (2021) this meeting. [5]Nakamura T. et al. (2021) this meeting. [6] Noguchi T. et al. (2021) this meeting. [7] Okazaki R. et al. (2021) this meeting. [8]Yabuta H. et al. (2021) this meeting. [9] Naraoka H. et al. (2021) this meeting. [10] Tsuchiyama A. et al. (2021) this meeting.
[11] Dionnet Z. et al. (2021) this meeting. [12] Rubino S. et al. (2021) this meeting. [13] Viennet J.-C. et al. (2021) thismeeting. [14] Matsumoto T. et al. (2021) this meeting. [15] Nishiizumi K. et al. (2021) this meeting. [16] Kebukawa Y. et al.
(2021) this meeting. [17] Bonal L. et al. (2021) this meeting. [18] Stroud R. M. et al. (2021) this meeting. [19] Nittler L. R. etal. (2021) this meeting. [20] Takano Y. et al. (2021) this meeting. [21] Orthous-Daunay F.-R. et al. (2021) this meeting. [22]Schmitt-Kopplin P. et al. (2021) this meeting.

Progress of chemical characterization of asteroid Ryugu samples
The Hayabusa2-initial-analysis chemistry team1,
T. Nakamura , T. Noguchi , R. Okazaki2, H. Yabuta2, H. Naraoka2, K. Sakamoto2, S. Tachibana2, S. Watanabe2 and Y. Tsuda2
2

2

1

2

See end of this abstract
Tohoku Univ., Kyoto Univ., Kyushu Univ., Hiroshima Univ., Kyushu Univ., JAXA, Tokyo Univ., Nagoya Univ. and JAXA

It is believed that meteorites come from asteroids. Samples of asteroid (25143) Itokawa returned by the JAXA Hayabusa
mission revealed that S-type asteroids are composed of materials consistent with the ordinary chondrite class [1, 2]. The JAXA
Hayabusa2 [3] spacecraft launched on December 3rd, 2014 towards an asteroid (162173) Ryugu to clarify relationships
between C-type asteroids and the carbonaceous chondrite class. Remote sensing observations from Hayabusa2 show that (1)the albedo of Ryugu is darker than those of every known meteorite class [4, 5], (2) an absorption band at 2.72 µm indicatesthat phyllosilicates are ubiquitous on Ryugu [5], (3) the strength and shape of the absorption band feature suggests that Ryugu
materials experienced heating above 300 °C [6], and (4) thermal inertia suggests that Ryugu materials are more porous thanevery known carbonaceous chondrite [7]. These results suggest that carbonaceous chondrite class materials are plausible for
Ryugu materials, but no known carbonaceous chondrite completely matches the results obtained from Ryugu.
The Hayabusa2 spacecraft made two successful landings operations onto Ryugu to collect asteroidal materials in 2019and delivered the collected samples to the Earth on December 6th, 2020. The returned samples are detritus from pebbles to clay,
exceeding 5 grams in total. Their colors, shapes and macro-structures are consistent with those of the remote sensing
observations, indicating that the returned samples are representative of the asteroid Ryugu [8]. The initial analysis of the
Ryugu samples began in June 2021. At that time, samples totaling ~125 mg, containing powder and particles from the 1st and2nd touchdown sites, were allocated to the Initial Analysis Chemistry Team.
The goals of the Initial Analysis Chemistry Team analyses are to provide fundamental answers to questions relating to
the provenance of Ryugu samples for in-depth research by international scientists in the future: (i) What are the elemental
abundances of Ryugu? (ii) What are the isotopic compositions of Ryugu? (iii) Does Ryugu consist of primary materials formedin the protosolar disk or secondary materials altered on the parent body? (iv) When were Ryugu materials formed? and (v)What are the relations to known meteoritic samples?
Hydrogen, C and S are analyzed by combination of thermogravimetric analysis coupled with mass spectrometry (TGMS) and by pyrolysis and combustion analyses (EMIA-Step). Major and minor elements are analyzed by X-ray fluorescenceanalysis (XRF) using laboratory X-rays and synchrotron radiation. Trace elements are analyzed by inductively coupled plasma
mass spectrometry (ICP-MS) using calibration curve and isotope dilution methods after acid digestion. We quantify theabundance of 66 elements in Ryugu samples: H, Li, Be, C, O, Na, Mg, Al, Si, P, S, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni,
Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, In, Sn, Te, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy,
Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Tl, Pb, Bi, Th, and U. Inorganic and organic element concentrations are also analyzed for H
and C.
For isotope analyses, the Ryugu samples are digested with acids, and the target elements are successively separated byion-exchange column chromatography. We use thermal ionization mass spectrometry (TIMS) and ICP-MS with multicollectors to measure isotope ratios. We determine isotope ratios for chronological systems of Rb-Sr, Sm-Nd, U-Th-Pb, Lu-Hf,
Hf-W, Re-Os, Al-Mg, and Mn-Cr. We also determine stable isotope systematics of Ca, Ti, Cr, Fe, Ni, Sr, Ba, Zr, Mo, Ce, Gd,
Ru and Nd to test isotopic dichotomy in the solar system. Oxygen isotope systematics of Ryugu are measured by laserfluorination isotope-ratio mass-spectrometry (LF-IRMS) for bulk samples and by secondary ion mass spectrometry (SIMS) for
individual components in the samples. The SIMS technique is also applied to the Mn-Cr chronological systematics todetermine ages of aqueous alteration. Surveying for circumstellar and molecular cloud matter is conducted by isotope
microscope and NanoSIMS.
References[1] Yurimoto H. et al. 2011. Science 333: 1116. [2] Nakamura T. et al. 2011. Science 333: 1113. [3] Tachibana S. et al. 2014.
Geochem. J. 48: 571. [4] Kitazato K. et al. 2019. Science 364: 272. [5] Sugita S. 2019. Science 364, eaaw0422. [6] Kitazato K.
et al. 2021. Nature Astronomy 5: 246. [7] Okada T. et al. 2020. Nature 579: 518. [8] Tachibana S. et al. 2021. in review.

The Hayabusa2-initial-analysis chemistry team:
H. Yurimoto1, T. Yokoyama2, K. Nagashima3, I. Nakai4, Y. Abe5, Y. Terada6, S. Komatani7, M. Morita7, K. Ichida7, H.
Homma8, K. Motomura8, K. Yui4, T. Usui9, M. K. Haba2, T. Iizuka10, S. Yoneda11, H. Hidaka12, K. Yamashita13, M. Bizzarro14,
F. Moynier15, M. Schöenbächler16, T. Kleine17, N. Dauphas18, Q-Z. Yin19, M. Wadhwa20, R. J. Walker21, R. W. Carlson22, A.
Bouvier23, Y. Amelin24, L. Qin25, I. Gautam2, R. Fukai9, Y. Masuda2, Y. Hibiya10, A. Ishikawa2, A. Pack26, E. D. Young27, C.
Park28, N. Sakamoto1, W. Fujiya29, N. Kawasaki1, S. Itoh30, K. Terada31, M. Ito32, M. Chaussidon15, J. Aleon33, L. Piani34, S.
Russell35, P. Hoppe36, S. Amari37, K. D. McKeegan27, M-C. Liu27, G. R. Huss3, A. N. Krot3, C. M. O’D. Alexander22, L. R.
Nittler22, A. M. Davis18, A. Nguyen38, N. Kita39, K. Kitajima39, T. R. Ireland40, B-G. Choi41, A-C. Zhang42, K. Bajo1
1

Hokkaodo Univ., 2Tokyo Tech., 3Univ. Hawai‘i, 4Tokyo Univ. Sci. 5Tokyo Denki Univ., 6SPring-8, 7HORIBA TECHINOSERVICE Co., Ltd., 8Rigaku Co., 9JAXA, 10Univ. Tokyo, 11National Museum Nature Sci. Tokyo, 12Nagoya Univ. 13Okayama
Univ., 14Natural History Museum Denmark, 15Inst. Phys. Globe Paris, 16ETH, 17Univ. Münster, 18Univ. Chicago, 19UC Davis,
20
ASU, 21Univ. Maryland, 22Carnegie Inst. Sci., 23Univ. Bayreuth, 24ANU, 25China Univ. Geosci., 26Univ. Göttingen, 27UCLA,28
KOPRI, 29Ibaraki Univ., 30Kyoto Univ., 31Osaka Univ., 32JAMSTEC, 33MNHN, 34CRPG, 35NHM, 36MPI Chemistry,
37
Washington Univ. St. Louis, 38NASA, 39Univ. Wisconsin, 40Univ. Queensland, 41SNU, 42Nanjing Univ.

Initial analysis of “stone” size Ryugu samples: current status
Tomoki Nakamura1, Megumi Matsumoto1, Kana Amano1, Yuma Enokido1, Mike Zolensky2, Takashi Mikouchi3, Yuri Fujioka1,
Mizuha Kikuiri1, Eiichi Kagawa1, Daisuke Nakashima1, Adrian Brearley4, Mikhail Zolotov5, Akira Tsuchiyama6, Masayuki
Uesugi7, Yoshio Takahashi3, Moe Matsuoka8, Ralph Milliken9, Donald Brownlee10, David Joswiak10, Miki Takahashi1,
Kazuhiko Ninomiya11, Tadayuki Takahashi3, Takahito Osawa12, Kentaro Terada11, Frank E. Brenker13, Beverley Tkalcec13,
Yuki Kimura14, Satoshi Tanaka8, Housei Nagano15, Rosario Brunetto16, Alice Aléon-Toppani16, Queenie Chan17, Mathieu
Roskosz18, Esen Ercan Alp19, Pierre Beck20, Aiko Nakato8, Takaaki Noguchi21, Masahiko Tanaka22, Takahiro Hiroi9, Eri
Tatsumi23, Faith Vilas24, Amanda R. Hendrix24, Camilo Jaramillo25, Gerardo Dominguez26, Cecile Engrand16, Jean Duprat16,
Hidenori Genda27, Kousuke Kurosawa28, Sara Russell29, Ashley King29, Enrica Bonato30, Chi Ma31, Kentaro Uesugi7, Akihisa
Takeuchi7, Jyunya Matsuno21, Akira Miyake21, Satomi Enju32, Masahiro Yasutake7, Toru Matsumoto33, Shota Okumura21, Aki
Takigawa3, Shohei Yamashita34, Takahiro Kawai3, Jean-Christophe Viennet18, Barbara Lavina19, Toshiaki Tanigaki35, Kazuo
Yamamoto36, Deborah Domingue Lorin24, Ferenc Borondics37, Zélia Dionnet16, Donia Baklouti16, Zahia Djouadi16, Cateline
Lantz16, Stefano Rubino16, Laszlo Vincze38, Bart Vekemans38, Gerald Falkenberg39, Pieter Tack38, Ella De Pauw38, Miles
Lindner13, Benjamin Bazi38, Shinya Yamada40, Kenya Kubo41, Shunsaku Nagasawa3, Taiga Wada1, Satoshi Takeshita34,
Akihiro Taniguchi21, Shin Watanabe3, 8, Izumi Umegaki34, Chiu I-Huan11, Yasuhiro Miyake34, Kosuke Inoue42, Seiji Sugita3,
Kohei Kitasato43, Hisayoshi Yurimoto14, Ryuji Okazaki33, Hikaru Yabuta44, Hiroshi Naraoka33, Kanako Sakamoto8, Shogo
Tachibana3,8, Seiichiro Watanabe15, Yuichi Tsuda8 and the Hayabusa2-initial-analysis Stone team.
1Tohoku University, Japan, 2NASA/JSC, USA, 3The University of Tokyo, Japan, 4University of New Mexico, USA, 5Arizona State University,

USA, 6Ritsumeikan University, Japan and CAS, GIG, China, 7JASRI/SPring-8, Japan, 8ISAS/JAXA, Japan, 9Brown University, USA,
10University of Washington, USA, 11Osaka University, Japan, 12Japan Atomic Energy Agency, Japan, 13Goethe University Frankfurt,
Germany, 14Hokkaido University, Japan, 15Nagoya University, Japan, 16University of Paris-Saclay, France, 17University of London, UK,
18Muséum National d'Histoire Naturelle, France, 19Argonne National Laboratory, USA, 20Université Grenoble Alpes, France, 21Kyoto
University, Japan, 22National Institute for Materials Science, Japan. 23 Instituto de Astrofísica de Canarias, Spain,, 24Planetary Science
Institute, USA, 25Pensylvania State University, 26Callfornia State University, USA, 27Tokyo tech, Japan, 28Chiba tech, Japan, 29Natural
History Museum, UK, 30Deutsches Zentrum für Luft- und Raumfahrt, Germany, 31Caltech, USA, 32Ehime University, Japan, 33Kyusyu
University, Japan, 34High Energy Accelerator Research Organization (KEK), Japan, 35Hitachi, Ltd., Japan, 36Japan Fine Ceramics
Center, Japan, 37SOLEIL Synchrotron, France, 38Ghent University, Belgium, 39DESY, Germany, 40Rikkyo University, Japan,
41International Christian University, Japan, 42Kanazawa University 43University of Aizu, Japan, 44Hiroshima University, Japan.

As a part of the initial analysis of the Ryugu samples, we perform a variety of analyses of millimeter-sized "stones". Our
goals are to elucidate the entire formation process of Cb-type asteroid Ryugu from the viewpoint of petrology and mineralogy
and obtain necessary information by sample analysis, and then simulate the formation of Ryugu based on the evidence
obtained from sample analysis. Eighteen stones (8 from the chamber A and 10 from the chamber C) were received from the
ISAS curation facility on June 1, 2021, and placed into a fully nitrogen-displaced glove box at Tohoku University. At the sametime, we also received the powder samples from the chamber A and the chamber C. All the allocated samples were put in thesample transport containers prepared by ISAS in the nitrogen atmosphere inside the clean chamber system dedicated to Ryugu
samples. The containers were then transferred to the nitrogen glovebox at ISAS, where all the containers were completely
sealed in plastic bags with moisture and oxygen absorbers. No moisture or oxygen was detected when the bags were opened in
the glove box at Tohoku University, so it was confirmed that there was no exposure to the atmosphere during transport.
To date, a number of analyses have been carried out successfully and within schedule margins. The analysis started with themeasurement of reflectance spectra, which are sensitive to atmospheric oxidation, hydroxylation, and adsorbed water. The
ultraviolet, visible, near-infrared, and mid-infrared reflectance spectra were measured while the samples were kept airtight.
The spectra of powder samples and stone samples (as aggregates and as a single stone) were successfully obtained. Concurrent
with the analyses described below were ultra-violet spectral observations on stone samples, also transported and performed in
an inert environment, conducted at the University of Illinois Urbana-Champaign (USA).
A major feature of the stone team's analysis is the use of synchrotron radiation facilities around the world. Since thisanalysis is non-destructive, stone samples whose reflectance spectra were measured were sent to KEK, SPring-8, ESRF
(France), SOLEIL (France), DESY (Germany), and APS (USA). Using these synchrotron radiation facilities, high spatial
resolution and sensitivity XRD, STXM, XANES, CT [1], IR-CT, FT-IR [2, 3], XRF, and Mössbauer [4] analyses were
performed. Most of the analyses were carried out under airtight conditions on the stone samples and the particulates separated
from the stone samples. These analyses allowed us to determine the three-dimensional distribution of solid phases andelements, redox state, density, and porosity of the stone samples.
Furthermore, as a characteristic analysis of the stone team, light elemental analysis using negative Muon was performed at the
MLF facility of J-PARC with an exceptionally long allocation of machine time. This is the non-destructive method to measure
the concentration of light elements in the whole (not the surface) of stone samples. Because the characteristic X-rays produced

by muon irradiation are much higher in energy than the fluorescent X-rays produced by X-ray irradiation, there is little effectof self-absorption by the sample, and therefore, the concentration of light elements such as carbon, oxygen, and sodium in theentire "stone" sample can be determined.
Some stone samples are currently being measured for thermal conductivity and strengths in order to understand the physicalproperties of asteroid Ryugu. The data obtained from these measurements are useful for interpreting the remote-sensing data
data taken from the surface layer of the asteroid Ryugu [5-8]. It is also important for understanding the behavior of the Ryugu
material during impact events.
The surfaces of many stone samples were observed by electron microscopy and other techniques, especially on natural “flat”
surfaces formed on 5 stones. As a result, characteristric mineral aggregates formed by the reactions with water andcharacteristic impact features were observed on some samples. Based on the observations of surfaces and the synchrotron
measurements of the whole stones, important objects such as characteristic structures and specific crystal aggregates forunderstanding the formation history of the asteroid were identified, and these parts were separated from the stone samples
using a Xe beam (pFIB) and analyzed by various methods including transmission electron microscopy and synchrotron
radiation analysis. Many stone samples, from which important objects have been separated, are embedded in epoxy resin andcut to produce many polished sections. Electron microscopy and spectroscopic measurements of the polished surfaces arebeing carried out to reveal the detailed mineralogical properties and elemental distribution inside the stone samples. In this fall,
the allocate beam time for synchrotron radiation will begin, and we plan to analyze single crystals and characteristic objects
separated from the stone samples. Photometric measurements in the ultra-violet and visible to near-infrared will also be madethis fall on the powders produced in the structural experiments to facilitate comparisons with the ONC-T and NIRS3 remotesensing observations.
Acknowledgement
We thank Drs. H. Nakao (KEK), K. Nitta (JASRI/SPring-8), O. Sekizawa (JASRI/SPring-8) for support in synchrotron
analysis and Dr. O. Sasaki for support in CT analysis at Tohoku University.
References[1] Tsuchiyama A. et al. in this volume. [2] Dionnet Z. et al. in this volume.[3] Rubino S. et al. in this volume. [4] Viennet J-C.
et al. in this volume [5] Watanabe S. et al. 2019. Science 364:268.[6] Sugita S. et al. 2019. Science 364:252. [7] Kitazato K. et
al. 2019. Science 364:272. [8] Okada T. et al. 2020. Nature 579:518.

Mineralogy and surface modification of small grains recovered from the asteroid 162173 Ryugu
T. Noguchi1, T. Matsumoto1, A. Miyake1, Y. Igami1, M. Haruta1, H. Saito2, S. Hata2, Y. Seto3, M. Miyahara4, N. Tomioka5, H.
A. Ishii6, J. P. Bradley6, K. Ohtaki6, E. Dobrică6, T. Nakamura7, M. Matsumoto7, A. Tsuchiyama8, 9; M. Yasutake10, J.
Matsuno8, S. Okumura1, K. Uesugi10, M. Uesugi10, A. Takeuchi10, M. Sun9, S. Enju11, A. Takigawa12, H. Leroux13, C. Le
Guillou13, D. Jacob13, M. Marinova13, F. de la Peña13, F. Langenhorst14, D. Harries14, P. Beck15, T. H. V. Phan15, R. Rebois15,
N. M. Abreu16, T. Zega17, P.-M. Zanetta17, M. Thompson18, M. Lee19, L. Daly19, P. A. Bland20, R. Stroud21, K. Burgess21, J. C.
Bridges22, L. Hicks22, M. E. Zolensky23, D. R. Frank6, J. Martinez24, H. Yurimoto25, K. Nagashima6, N. Kawasaki25, R.
Okazaki2, H. Yabuta4, H. Naraoka2, K. Sakamoto26, S. Tachibana12, S. Watanabe27, Y. Tsuda26, and the Hayabusa2 Initial
Analysis Team1
2
3
Kyoto Univ., Japan; Kyushu Univ., Japan; Kobe Univ., Japan; 4Hiroshima Univ., Japan; 5Kochi Core
Center, JAMSTEC, Japan; 6Univ. of Hawaii, USA; 7Tohoku Univ., Japan; 8Ritsumeikan Univ., Japan; 9Guangzhou Instituteof Geochemistry, China; 10JASRI, Japan; 11Ehime Univ., Japan; 12Univ. of Tokyo, Japan; 13Univ. de Lille, France; 14Univ. ofJena, Germany; 15Univ. Grenoble Alpes, France; 16Penn State, USA; 17Univ. of Arizona, USA; 18Purdue Univ., USA; 19Univ. of
Glasgow, UK; 20Curtin Univ., Australia; 21US Naval Research Laboratory, USA; 22Univ. of Leicester, UK; 23JSC/NASA, USA;
24
Jacobs Engineering, USA, 25Hokkaido Univ., Japan; 26JAXA/ISAS, Japan; 27Nagoya Univ., Japan
Introduction: Surface material on airless bodies exposed to the interplanetary space experienced the bombardment by lowenergy (~1 keV/nucleon) solar wind particles and micrometeoroid impacts. These processes, alongside the resultant surface
modifications, and spectral darkening and reddening are called space weathering [1]. Space weathering of the Moon and theasteroid 25143 Itokawa belonging to S-type asteroids have been investigated intensively [e.g. 1-5]. The Hayabusa 2 spacecraft
returned samples from the asteroid 162173 Ryugu C-type asteroid. The Ryugu samples give us the first opportunity toinvestigate space weathering of C-type asteroids. The Mineralogy-Petrology Fine (M-P F or Sand) sub-team mainly
investigates small grains (typically ~100 µm across). The main purposes of the M-P F sub-team are to understand the variationof mineralogy of the allocated grains and the nature of space weathering of the asteroid Ryugu. The M-P F sub-team iscomprised of 51 members belonging to 25 universities and laboratories.
Sample and methods: Numerous small Ryugu grains, ~100 µm across on average, were allocated to the M-P F sub-team.
Surface morphology of >350 grains from the chamber A of the sample canister have been observed by JEOL JSM-7001F fieldemission scanning electron microscope (FE-SEM) at Kyoto Univ. and by Thermo Scios focused ion beam (FIB)-SEM at
Kyushu Univ. Elemental mapping analysis was also performed using Energy dispersive spectrometer (EDS) equipped on the
FE-SEM. Most of the grains were attached to Au plates with small amounts of epoxy glue in N2 filled glove box for SEM
observation. Some grains were just placed on Pt plates without using any glue to make FIB sections in response to requests
from some members. One sample was prepared by Reichelt Ultracut ultramicrotome at Kyoto Univ. In addition to the small
grains, the Chemistry sub-team loaned a polished sample of a fragment originating from a large grain A0026 (~3 mm wide)
because the sample has a bubble-rich material on its surface. Seven samples were able to be prepared for the detailed analysis.
Up to now we have prepared ~80 FIB sections from 40 grains and >30 FIB sections have already been distributed to themembers. To understand mineralogy and petrology down to the nanometer of these grains and to clarify the detailed
mineralogical analyses of space weathering of the C-type asteroid Ryugu, we are now performing (scanning) transmission
electron microscopy ((S)TEM), synchrotron radiation X-ray absorption fine structure (XANES and EXAFS) analysis, nanotomography, and atom probe analysis at 15 universities and laboratories.
Results: Major minerals of the small Ryugu grains are phyllosilicates (saponite and serpentine), Fe-bearing sulfides, magnetite,
dolomite, and a lesser amount of breunnerite. It is obvious that the asteroid Ryugu experienced severe aqueous alteration anddid not experience heating enough to make secondary anhydrous minerals such as olivine, pyroxene and Fe metal, which arecommon in severely heated carbonaceous chondrites. Serpentine in these Ryugu grains may have better crystallinity than thatin Orgueil and Ivuna CI chondrites [e.g., 6]. Typical spacing of (001) of saponite is ~1.0-1.3 nm, which suggests partial
dehydration of interlayer H2O molecules. Minor minerals so for observed are hydroxyapatite, ilmenite, magnesiochromite,
manganochromite, Cr oxide, Cu-bearing ZnS, (Fe, Ni)2P, FeCr2S4, cubanite, Na- and Mg-bearing phosphate, forsteritic olivine,
and Fe-free low-Ca pigeonite. A moissanite crystal was also identified, which could be a presolar grain.
The surfaces of the most Ryugu grains investigated have highly euhedral pyrrhotite crystals. Their surfaces preserve quite
sharp steps, which may reflect growth or dissolution in aqueous solutions. Magnetite crystals that form framboidal aggregateshave shapes as rounded as those in Orgueil and Ivuna. In addition, some magnetite crystals have facets as sharp as those inTagish Lake C ungrouped meteorite. The presence of these Fe sulfide and oxide suggests that these surfaces did not experienceenough exposure to the interplanetary space to degrade the surfaces of these minerals.
After scrutinizing >350 small Ryugu grains by FE-SEM and FIB-SEM, we found 10 small Ryugu grains having obviously
different surface morphology. Figure 1 shows an example of such grains with abundant open bubbles. The bubble-rich surfaces
form a continuous layer containing abundant bubbles. In Fig. 1(b), the bubble walls are as thick as ~0.5 µm at the thickest
places. Most bubble-rich layers have ~50 - ~500 nm thick, but the layer of A0026 has up to ~3 µm thick. The bubble-rich layer
in Fig. 1(b) is amorphous and contains abundant tiny Fe sulfide crystals based on selected area electron diffraction (SAED)
patterns and electron diffraction mapping. Preliminary analysis of energy-loss near-edge structures of Fe L2, 3 edge of the
bubble-rich layer and the subsurface phyllosilicate suggests that the former is much more enriched in Fe2+ than the latter. Moredetailed description of the rugged Fe sulfide and the other phases will be presented in another presentation [7].

Fig. 1 Secondary electron and annular dark-field images of a small Ryugu grain with a bubble-rich surface. (a) The surface iscovered by a gently rolling layer with abundant open bubbles. Abundant bright tiny speckles are on the surface. (b) A crosssection of the bubble-rich layer and the interior. Abbreviations: Po: pyrrhotite; Phy: phyllosilicate; depo: deposition.
Discussion and conclusion: These major minerals and the petrography of the small Ryugu grains indicate that the asteroid
Ryugu experienced severe aqueous alteration that can be classified as C1. The mineralogy and petrology of these grains are
similar to CI chondrites but these grains lack ferrihydrite and sulfates, both common among CI chondrites [e.g., 6, 8 andreferences therein]. The formation of ferrihydrite and sulfates may have occurred by terrestrial weathering. The spacing of(001) of saponite increased to ~1.3 nm on average by using ethylene glycol as the trough liquid during ultramicrotomy, whichmeans that saponite in the Ryugu samples can rehydrate.
Morphology of the bubble-rich layers is apparently similar to melt sheets (Fig. 1a). However, it does not necessarily mean that
all the layers were formed through melting by meteoroid impacts. The formation of similar bubble-rich amorphous layers by
H+ or He+ ion irradiation has already been reported [9-11]. Although the size and number density of bubbles in the amorphouslayer are different from the irradiation experiments and the natural samples, the difference can be interpreted by the different
fluxes between them. Therefore, we believe that at least thin bubble-rich layers were related to solar wind irradiation. Unlike
the irradiation experiments, the bubble-rich layer in Fig. 1(b) is more enriched in Fe, S, and Ca than the subsurfacephyllosilicate. Recondensation of elements derived from the surrounding phases may have also played a role in thecompositional difference. Because the thickness of the bubble containing layer is quite variable, the relative contribution ofirradiation and micrometeoroid impacts that resulted in vaporization and recondensation of elements may be quite different atplaces. The M-P F sub-team continues to assess the role of recondensation in the space weathering of the Ryugu C-type
asteroid. Although small Ryugu grains with the space weathering rims are quite rare among the investigated samples, it does
not necessarily mean that such grains are rare on the surface of Ryugu because most of the surfaces are exposed to theinterplanetary space may have been destroyed during the sampling sequence using Ta projectiles. If most of the space exposed
surface had the bubble-rich amorphous layer on Ryugu, the bubble-rich amorphous surface layers might have affected thereflectance spectra of the asteroid Ryugu.
References [1] Noguchi T. et al. 2011. Science 333, 1121-1125. [2] Noguchi T. et al. 2014. Meteorit. Planet. Sci. 49, 188-214.
[3] Matsumoto T. et al. 2015 Icarus 257, 230-238. [4] Thompson, M. et al. 2014. Earth Planet. Space 66, 89. [5] Burgess K.D.
and Stroud K.D. 2018. J. Geophys. Res. Planets 123, 2022-2037. [6] Tomeoka K. and Buseck P. 1985 Geochim. Cosmochim.
Acta 52, 1627-1640. [7] Matsumoto T. et al. this symposium. [8] Brearley A. and Jones R. 1998. Planetary Materials, pp. C1.
[9] Thompson M. et al. 2020. Icarus 346, 113775. [10] Laczniak D.L. et al. 2020. Icarus 364, 114479. [11] Noguchi T. et al.
2017. Hayabusa 2017 Symp. & 8th Symp. Pol. Sci. (abstract).

Initial Analysis of Volatile Components in the Hayabusa2 Samples
Ryuji Okazaki1, Bernard Marty2, Henner Busemann3, Yayoi N. Miura4, Keita Yamada5, Saburo Sakai6, Ko Hashizume7, Kenichi Bajo8, Shun Sekimoto9, Fumio Kitajima1, Kevin Righter10, Alex Meshik11, Jamie Gilmour12, Naoyoshi Iwata13, Evelyn
Füri2, Sarah Crowther12, Naoki Shirai14, Mitsuru Ebihara15, Yoshinori Takano6, Akizumi Ishida16, Reika Yokochi17, Olga
Pravdivseva11, Jisun Park18, 19, Toru Yada20, Kunihiko Nishiizumi21, Keisuke Nagao22, Jong Ik Lee22, Michael Broadley2,
David Byrne2, My Riebe3, Patricia Clay12, Akihiro Kano4, Marc Caffee23, Shinsuke Kawagucci6, Yohei Matsui6, Ryu
Uemura24, Makoto Inagaki9, Daniela Krietsch3, Colin Maden3, Mizuki Yamamoto1, Hisayoshi Yurimoto8, Tomoki
Nakamura16, Takaaki Noguchi9, Hiroshi Naraoka1, Hikaru Yabuta25, Kanako Sakamoto20, Shogo Tachibana4, 20, Sei-ichiro
Watanabe24 and Yuichi Tsuda20
1

Kyushu Univ., 2CRPG, 3ETH, 4Univ. of Tokyo., 5Tokyo Inst. Tech., 6JAMSTEC, 7Ibaraki Univ., 8Hokkaido Univ., 9Kyoto U.,
10NASA JSC, 11Washington Univ., 12Univ. Manchester, 13Yamagata Univ., 14Tokyo Metro., 15Waseda Univ., 16Tohoku Univ.,
17
Chicago Univ., 18Kingsborough Comm. Coll., ,19AMNH, 20JAXA, 21UC Berkeley, 22KOPRI, 23Purdue Univ., 24Nagoya Univ.,
25
Hiroshima Univ.

The major objectives of the Hayabusa2-initial-analysis volatile team are (1) to determine the pristine volatile components inthe parental materials of the returned Ryugu samples, and (2) to elucidate the origin and chronological history of the asteroid
Ryugu, as well as the evolution of the solar system through determination of volatile carrier phases and abundances of volatilecomponents (e.g., presolar grain abundances). Our analytical data will be linked with remote sensing (NIRS3, ONCs, TIR, and
LIDAR) data and theoretical modeling [e.g., 1-5]. For example, the erosion rate and the degree of gardening of the surface layerof the asteroid Ryugu can be estimated based on trapped solar wind (SW) and cosmic ray produced (cosmogenic) nuclides,
which will be discussed in conjunction with the results based on the remote sensing data [3-5]. Taken together, these will provide
characteristics of the surface materials, such as the degree and duration of the alteration by SW/cosmic ray irradiation andmicrometeorite bombardments.
Our analytical plan for the Ryugu samples consists of three approaches (Fig. 1): One is analyses of native volatiles in the
Ryugu samples which have been treated WITHOUT air-exposure throughout the whole process, since the collection from theasteroid Ryugu to the gas extraction in the laboratories. The goal of this work is to quantify the indigenous compositions with as
minimal terrestrial (atmospheric, biological, and unintentional man-made pollution) contamination as possible. We will obtain

Figure 1.

Analytical flow of the volatile team of the Hayabusa2 initial analysis.

the abundances and isotopic compositions of nitrogen, noble gases, and volatile elements (e.g., H and C in H2, CO, and CO2,methane, and ethane).
The second approach is analyses of the neutron-irradiated samples to determine the Ar-Ar and I-Xe ages and halogen
abundances by noble gas isotope measurements at U. Manchester and Kyushu U., and to obtain abundances of minor/traceelements (e.g., Co, Ni, and Ir) by neutron activation analysis (NAA) at KURNS. Prior to neutron-irradiation, nanoSIMS analysis
will be carried out at AORI on the same samples that are used for the Ar-Ar/I-Xe/halogen analysis at Kyushu U. to understandthe distribution and isotopic compositions of volatile elements (H, C, N, and O).
The third approach is measurements of cosmogenic long-lived nuclides and noble gas isotopes, which are performed for
different samples prepared under an atmospheric environment. The preliminary result of cosmogenic nuclides is reported by [6].
Most of Hayabusa2 samples allocated to the volatile team have been transported to Kyushu Univ. from JAXA, and locatedin a N2 glove box installed at Kyushu Univ., and pelletized without air-exposure in June 2021, except for two particles for thevolatile element analysis at TITECH/JAMSTEC and five samples for cosmogenic nuclides which were directly allocated toBerkeley U. from JAXA. Twenty four pellets have been prepared (Fig. 2), and sent back to JAXA to perform FTIR and FESEM
observations. After these observations, 16 out of 24 samples have been distributed to our team laboratories, ETH, U. Manchester,
Washington U., CNRS-Nancy, Ibaraki U., TITECH/JAMSTEC, and Kyushu U. to measure native volatile compositions. Before
analysis, we measured the sample weight without air-exposure by using a small weighing container (Fig. 3). These careful
operations enable us to obtain the most intact, fresh volatile compositions of the asteroid Ryugu.

Figure 2. The Hayabusa2 samples pelletized onto a Cu disk without air-exposure (2a). The
Cu disk is installed in a metal holder for NanoSIMS analysis and transportation. Enlarged
view of the sample is shown in Fig. 2b.
Figure 3. The small weighing
container developed for the
Hayabusa2 initial analysis.

The remainder of the samples, six pellets have been transported to Tohoku U. and coated with Os and Pt as an antistatic
treatment. These samples have now been exposed to the atmosphere. After coating, the 6 samples were shipped to AORI andinvestigate with NanoSIMS in August 2021. The result of the nanoSIMS analysis will be reported by Drs. Hashizume andIshida somewhere else.
Following NanoSIMS analysis, the 6 pellet samples were transported to Kyushu U. for installation in diamond container
for the NAA. The neutron irradiation and NAA are scheduled to be completed in October. After the NAA, the 6 samples will
be analyzed for Ar-Ar age dating. For I-Xe dating and halogen analysis, two other pellet samples, different from the 6 samples
that have been analyzed for nanoSIMS and NAA, have been distributed to U. Manchester in July. Now all of these preparatory
steps are over and the Ryugu samples are ready for the experiments. We believe that all analyses will proceed successfully.
References[1] Sugita S. et al. 2019. Science 364, eaaw0422 1-11. [2] Kitazato K. et al. 2019. Science 364, 272-275. [3] Tatsumi E. et al.
2021. Nature Astronomy doi.org/10.1038/s41550-020-1179-z. [4] Morota T. et al. 2020. Science 368, 654–659. [5] Tachibana
S. et al. 2021. in review. [6] Nishiizumi K. et al. 2021. This issue.

An initial look at the distributions and compositions of organic macromoleculesin the asteroid Ryugu samples
Hikaru Yabuta1, George Cody2, Cecile Engrand3, Yoko Kebukawa4, Bradley De Gregorio5, Lydie Bonal6, Laurent Remusat7,
Rhonda Stroud5, Eric Quirico6, Larry Nittler2, Minako Hashiguchi8, Mutsumi Komatsu9, Taiga Okumura10, Yoshio Takahashi10,
Yasuo Takeichi11, Emmanuel Dartois3, Jean Duprat7, Jeremie Mathurin3, David Kilcoyne12, Zita Martins13, Scott Sandford14,
Shohei Yamashita11, Ariane Deniset3, Alexandre Dazzi3, Yusuke Tamenori15, Takuji Ohigashi16, Hiroki Suga15, Daisuke
Wakabayashi11, Maximilien Verdier-Paoletti7, Smail Mostefaoui7, Gilles Montagnac17, Jens Barosch2, Kanami Kamide1, Miho
Shigenaka1, Laure Bejach3, Takaaki Noguchi18, Hisayoshi Yurimoto19, Tomoki Nakamura20, Ryuji Okazaki21, Hiroshi
Naraoka21, Kanako Sakamoto22, Shogo Tachibana10, 22, Sei-ichiro Watanabe8, and Yuichi Tsuda22
1

Hiroshima Univ., 2Carnegie Institution of Washington, 3Université Paris Sud, 4Yokohama National Univ., 5Naval ResearchLaboratory, 6Université Grenoble Alpes, 7Muséum national d'Histoire naturelle, 8Nagoya Univ., 9The Graduate Univ. for
Advanced Studies (Sokendai)., 10Univ. of Tokyo, 11High Energy Accelerator Research Organization, 12Advanced Light Source,
13
Universidade de Lisboa, 14NASA Ames Research Center, 15SPring8, 16UVSOR, IMS, 17ENS de Lyon, 18Kyoto Univ.,
19
Hokkaido Univ., 20Tohoku Univ., 21Kyushu Univ., 22JAXA
Hayabusa2 is JAXA’s asteroid sample return mission that targeted the carbonaceous (C-type) asteroid (162173) Ryugu.
The mission aims to unveil the origin and evolution of organic compounds and water in the early Solar System as life’sbuilding blocks [1]. Following the arrival of the Hayabusa2 spacecraft at Ryugu on June 27, 2018, observations by onboard
remote sensing instruments revealed that Ryugu is a top-shaped asteroid with a very low geometric albedo [2-4] and that its
surface is probably partially dehydrated [5]. The Mobile Asteroid Surface Scout (MASCOT) lander observed two types ofboulders on the surface of Ryugu: one type was dark and cauliflower-like with a similar morphology to primitive carbonaceouschondrites, and another type was bright and smooth [6]. The lander’s radiometer revealed that Ryugu has low thermal
conductivity and high porosity unlike any chondritic meteorites, while these thermal properties have similar values to comets[7]. Thanks to the formation of the artificial crater on Ryugu’s surface by a small carry-on impactor [8], two successful
touchdowns on February 22 and July 11, 2019 have enabled collections of samples from two distinct locations on the asteroid,
providing an advantage for investigating the origin and evolution of the Solar System as well as the surface processes of theasteroid. After the sample return on December 6, 2020, the curatorial work on the Ryugu sample has been conducted at JAXA
for the first 6 months [9]. With the significant guidance from the observations and curation, the initial sample analysis has a
one-year mission from June 2021 to June 2022 to address the question of what kind of asteroid Ryugu is.
Organic compounds are a major component of interstellar dust as along with silicates and water ice due to the highabundances of their elements (C, H, O, N, S, P) in the Galaxy. The initial molecular inventory of the Solar System, inheritedfrom the parental molecular cloud, was modified and new complex molecules formed through a variety of processes in the
protoplanetary disk and planetesimals, which resulted in the diverse compositions of asteroids and comets. These small bodies
are thought to have contributed to the formation of our habitable planet, through exogenous delivery of organics and water as
life’s building blocks to the early Earth.
Organic macromolecules from chondritic meteorites have been often characterized as a dark, complex, acid-insolubleorganic matter (IOM). IOM accounts for a major portion of total organic carbon in primitive carbonaceous chondrites (CCs).
The intact chemical structure of IOM in CCs is still unknown, although a number of previous studies have suggested that it iscomposed of aromatic network crosslinking with short-branched aliphatic chains and various oxygen-bearing functionalgroups [10, 11]. Whether IOM was formed in interstellar cloud [12], outer solar nebula [13] or planetesimals [14], is still under
debate. Nevertheless, elemental, molecular and isotopic variations of IOM from various types of small body materials, such as
chondritic meteorites [15-20], interplanetary dust particles (IDPs) [21], cometary dusts [21-23], and Antarctic micrometeorites(AMMs) [24-27], have enabled our comprehensive understanding of chemical history of the early Solar System.
The Hayabusa2-initial-analysis IOM team consists of 36 members from Japan, USA, France, and Portugal. The scientificgoals of IOM team include: i) Decoding the chemical relationship(s) between organics and minerals on a C-type asteroid
parent body, ii) Elucidating formation pathways of organic macromolecules in a C-type asteroid, iii) Determining the origin(s)of organics in a C-type asteroid, iv) Investigating the asteroid-comet continuum, v) better understanding Solar Systemformation and volatile delivery, and vi) Understanding the role of organic macromolecules in the origin of life. In order toaccomplish the goals, we aim to unveil the elemental, isotopic, and functional group compositions, structures and textures oforganic macromolecules from the Ryugu samples. The analytical procedures are configured by combination of micro-Fourier

Transform Infrared Spectroscopy (FTIR), micro-Raman spectroscopy, synchrotron-based scanning transmission x-ray
microscope (STXM), Scanning Transmission Electron Microscopy (STEM) coupled with Electron Energy Loss Spectroscopy(EELS) and Energy Dispersive X-ray Spectroscopy (EDS), Atomic Force Microscope based Infrared Spectroscopy (AFM-IR),and nano-secondary ion mass spectrometry (NanoSIMS). The analytical procedures are applied to the intact Ryugu samples
and the IOM isolated by HCl/HF treatment of the Ryugu samples, respectively.
For the first measurements, Chamber A aggregates (A0108) collected upon the first touchdown and Chamber C aggregates(C0109) collected upon the second touchdown have been analyzed. The individual particles from A0108 and C0109 range
from 200 to 900 μm in size. Some of the particles were crushed on a diamond window for micro-FTIR, micro-Raman, andNanoSIMS. Slices of other particles were prepared with a focused ion beam workstation (FIB) and/or an ultramicrotome toobtain ultra-thin sections for STXM, STEM-EELS, AFM-IR and NanoSIMS. The water/solvent/HCl extraction residues ofother aggregates of Chamber A (A0106) and Chamber C (C0107), which were transferred by SOM team, were treated with 6N
HCl and 1N HCl/9N HF to yield IOM for future measurements.
Organic macromolecules have been identified from the Ryugu samples by all the analytical techniques. The organic
macromolecules were associated with secondary minerals formed through aqueous alteration [28], and they often exhibited D
and/or 15N-rich regions [29, 30]. These results show that the observed organics are of extraterrestrial origin. The FTIR [31] andRaman [32] spectroscopic features as well as the isotopic features [29, 30] of organic macromolecules from the Ryugu samples
were comparable with those of the primitive carbonaceous CI/CM chondrites, while the other features were not necessarily
consistent with the typical CI/CM, demonstrating that Ryugu samples record heterogeneous chemical history in a pristine state[28, 29].

References[1] Tachibana et al. 2014. Geochem. J. 48:571. [2] Watanabe et al. 2019. Science 364:268. [3] Sugita et al. 2019. Science 364:
eaaw0422. [4] Tatsumi et al. 2020 A&A, 639:A83. [5] Kitazato et al. 2019. Science 364:272. [6] Jaumann et al. 2019. Science
365:817. [7] Grott et al. 2019. Nature Astronomy 3:971. [8] Arakawa et al. 2020. Science 368:67. [9] Yada et al. et al. 2021.
under review. [10] Glavin et al. 2018. In: Primitive Meteorites and Asteroids: Physical, Chemical and Spectroscopic
Observations Paving the Way to Exploration (Ed. Abreu N.) pp. 205-271. [11] Martins et al. 2020. Space Sci. Rev. 216:54.
[12] Alexander et al. 2007. GCA 71:4380. [13] Remusat et al. 2010. Astrophys. J., 713:1048. [14] Kebukawa et al. 2013.
Astrophys. J. 771:19. [15] Cody and Alexander, 2005. GCA 69:1085. [16] Yabuta et al. 2005. GCA 40:779. [17] Bonal et al.
2006. GCA 70:1849. [18] Cody et al. 2008. Earth Planet. Sci. Lett. 272:446. [19] Kebukawa et al. 2011. GCA 75:3530. [20]Quirico et al. 2018. GCA 241:17. [18] Messenger, 2000. Nature 404:968. [21] Sandford et al. 2006. Science 314:1720. [22]
Cody et al. 2008. MAPS 43:353. [23] De Gregorio et al. 2011. MAPS 46:1376. [24] Duprat et al. 2010. Science 328:742. [25]Yabuta et al. 2017. GCA 214:172. [26] Noguchi et al. 2017. GCA 208:119. [27] Mathurin et al. 2019. A&A 622:A160. [28]Stroud et al. this conference. [29] Nittler et al. this conference. [30] Remusat et al. this conference. [31] Kebukawa et al. thisconference. [32] Bonal et al. this conference.

Soluble Organic Matter (SOM) analysis of the Hayabusa2 samples: The first results
Hiroshi Naraoka1, Yoshinori Takano2, Jason P. Dworkin3, Kenji Hamase1, Aogu Furusho1, Minako Hashiguchi4, Kazuhiko
Fukushima4, Dan Aoki4, Yasuhiro Oba5, Yoshito Chikaraishi5, Saburo Sakai2, Nanako O. Ogawa2, Naohiko Ohkouchi2,
Toshihiro Yoshimura2, Toshiki Koga2, Haruna Sugahara6, Hajime Mita7, Daniel P. Glavin3, Jamie E. Elsila3, Eric T. Parker3,
José C. Aponte3,8, Hannah L. McLain3,8, Heather V. Graham3, John M. Eiler9, Francois-Regis Orthous-Daunay10,
Cédric Wolters10, Véronique Vuitton10, Roland Thissen10, Junko Isa11, Philippe Schmitt-Kopplin12, Norbert Hertkorn12,
Alexander Ruf13, Hisayoshi Yurimoto5, Tomoki Nakamura14, Takaaki Noguchi15, Ryuji Okazaki1, Hikaru Yabuta16,
Kanako Sakamoto6, Shogo Tachibana6,17, Seiichiro Watanabe4 and Yuichi Tsuda6
1

Kyushu Univ.,2JAMSTEC, 3NASA Goddard Space Flight Center, 4Nagoya Univ., 5Hokkaido Univ., 6JAXA, 7Fukuoka Inst.
Tech. 8Catholic Univ/CRESST, 9California Inst. Tech., 10Univ. Grenoble Alpes CNRS IPAG, 11Tokyo Inst. Tech.,
12Helmholtz-Zentrum Muenchen, 13Aix-Marseille Univ., 14Tohoku Univ., 15Kyoto Univ. 16Hiroshima Univ., 17Univ. Tokyo

The Hayabusa2 spacecraft successfully collected the surface and possible sub-surface materials of the asteroid 162173 Ryugu.
Ryugu is a C-type asteroid characterized by a low-albedo surface probably consisting of hydrous minerals and carbonaceous
materials. [1] The direct optical and spectral analysis of the returned samples indicates that Ryugu material is dominated byhydrous carbonaceous chondrite-like matter (similar to CI chondrites) [2]. Since carbonaceous chondrites have generally
yielded various types of organic matter, the collected Ryugu grains are expected to contain diverse types of organic
compounds including bio-related molecules. The occurrence of organic compounds in the Ryugu surface will provide clues tothe evolution of prebiotic molecules and their preservations associated with aqueous alteration of the primitive asteroid. The
initial analysis of soluble organic matter (SOM) of the Hayabusa2-returned samples has been performed by an internationalteam consisting of 32 members. Because the sample amount available for comprehensive SOM analyses is limited, andbecause the SOM is expected to be present as a complex mixture of various types of organic compounds with very small
concentrations of each compound, high-sensitivity and high-resolution analytical techniques have been developed using
carbonaceous meteorites [e.g. 3].
Two aggregate samples of the Ryugu grains (A106 and C107) were allocated for the solvent extractions and total
carbon (C), hydrogen (H), nitrogen (N), sulfur (S) and oxygen (O) measurements. The A106 sample was collected during the
1st sampling in February 2019 and the C107 sample was collected during the 2nd sampling in July 2019 after the Small Carry
Impactor (SCI) operation. They consist mainly of particles smaller than 1 mm in diameter, and each sample mass was 38-39
mg. They were firstly investigated spectroscopically in the near infrared wavelength range by the Stone Team prior to thesolvent extractions. Other small grains (A0080 and C0057) were also allocated for this study to investigate the spatial
distribution of organic compounds on the sample surface. The extraction and analytical measurements implemented by the
SOM Team are summarized in Figure 1. Each powder sample was extracted sequentially with non-polar to polar solvents, i.e.,hexane, dichloromethane (DCM), methanol (MeOH) and H2O, for non-targeted analysis to reveal the compound composition.
Each solvent extract was analyzed by solution state nuclear magnetic resonance (NMR) spectroscopy [4], Fourier transformion cyclotron resonance/mass spectrometry (FT-ICR/MS) with ESI and APPI ionization [5] and by high-resolution mass
spectroscopy using Orbitrap MS coupled with nano-liquid chromatography (nanoLC/Orbitrap MS) [6], and using two
dimensional gas chromatography/mass spectrometry (GC×GC/MS). The extracted residues were passed to the Chemistry
Team for further inorganic element analysis. The other powder sample was subjected to the hot water extraction for amino acidanalyses including chiral isomer separation, which was performed by three-dimensional (3D) high-performance liquid
chromatography (HPLC) with high-sensitivity fluorescence detection (FD) [7] and by HPLC/FD coupled with quadrupole-timeof flight/mass spectrometry (QToF/MS) [8]. After the hot water extraction, the residue was split into two halves. One half was
further extracted with hydrochloric acid (HCl) to analyze for amino acids in bound-form. The other half was sequentiallyextracted with DCM/MeOH (1/1) to analyze semi-polar compounds such as polycyclic aromatic hydrocarbons (PAHs) by
GC/MS, followed by further extraction with formic acid to analyze polar heterocyclic compounds, and subsequent extraction
with HCl to detect bound-form polar compounds. The extracted residues were passed to the IOM Team for the analysis of
insoluble organic matter (IOM). Compound-specific stable isotope analyses will be performed using GC/combustion/isotope
ratio mass spectrometry (GC/C/IRMS) if the compound concentration is high enough to enable such an isotopic measurement.
All extraction procedures were performed on an ISO 6 (Class 100) clean bench inside an ISO 5 (Class 1000) clean room.
Baked serpentine powder was also analyzed as a procedural blank. In situ organic compound analysis with the molecularimaging was performed using desorption electrospray ionization (DESI) equipped with Orbitrap MS [9, 10], followed byspatial imaging of organic compounds using ToF/secondary ion mass spectrometry (ToF/SIMS) [11]. The bulk chemical andisotopic compositions of CNS and HO were determined using nano-elemental analysis/isotope ratio mass spectrometry(nanoEA/IRMS) [12] and EA/pyrolysis/IRMS, respectively.
We have identified a variety of indigenous organic compounds in the extracts of both A106 and C107 samples. The
Ryugu grains host organic molecules under the high-vacuum and cosmic-ray irradiation environment of the asteroid surface.
The analysis of extracted molecules is in progress, and the first results will be presented at the symposium.

Figure 1. Analytical scheme for the Ryugu samples by the SOM Team.

References[1] Kitazato K. et al. (2019) Science 364, 272. [2] Yada T. et al. (2021) Nature Astron. in press. [3] Naraoka H. et al. (2019)
Life 9, 62. [4] Hertkorn N. et al. (2015) Magn. Reson. Chem. 53, 754. [5] Schmitt-Kopplin P. et al. (2010) PNAS USA 107,2763. [6] Naraoka H. et al. (2017) ACS Earth & Space Chem. 1, 540. [7] Furusho A. et al. (2020) J. Chromatogr. A 1625,
461255. [8] Glavin D. P. et al. (2021) MAPS 56, 148. [9] Naraoka H. & Hashiguchi M. (2018) Rapid Commun. Mass Spectrom.
32, 959. [10] Hashiguchi M. & Naraoka H. (2019) MAPS, 54, 452. [11] Naraoka H. et al. (2015) EPS 67, 67. [12] Ogawa N. O.
et al. (2019) 82nd METSOC Meeting, Abstract #6208.

A first look at the interior and exterior of Ryugu preserved in samples collected by Hayabusa2
Eizo Nakamura1, Katsura Kobayashi1, Ryoji Tanaka1, Tak Kunihiro1, Hiroshi Kitagawa1, Christian Potiszil1, Tsutomu Ota1,
Chie Sakaguchi1, Masahiro Yamanaka1, Yusuke Yati1,Tomohiro Usui2, Yuichi Tsuda2, Seichiro Watanabe3, Masanao Abe2,
Tatsuaki Okada2, Toru Yada2
1
The Pheasant Memorial Laboratory, Inst. for Planetary Materials, Okayama Univ. at Misasa, Tottori 682-0193, Japan.
2Inst. Space Astronaut. Sci., Japan Aerosp. Explor. Agency (JAXA), Kanagawa 252-5210, Japan
3
Dept Earth Planet. Sci., Grad. Sch. Sci., Nagoya Univ., Nagoya 464-8601, Japan.
Sample return missions represent great opportunities to study materials from known locations. The Hayabusa mission returnedmaterial to Earth from the asteroid Itokawa in 2010 and revealed through geochemistry and micro-petrograpy that it isgenetically related to ordinary chondrite meteorites and the surface of the modern-day asteroid is being actively bombarded byhyper-velocity small particles (e.g., Kawaguchi et al., 2003; Nakamura et al., 2012). The Hayabusa2 mission returned material
to Earth from Ryugu on 6th of December, 2020 (Tsuda et al., 2020). Based on the very low geometric albedo indicated byremote observations (Sugita et al., 2019; Kitazato et al., 2019), abundant organic matter on Ryugu, compared to those incarbonaceous chondrites, might be expected (Potiszil et al., 2020). The initial uncontaminated and non-destructive
observations for the entire set of returned samples in the Phase-1 Curation at JAXA/ISAS (Yada et al., 2021) demonstrated
that Hayabusa2 retrieved the representative and unprocessed (albeit slightly fragmented) Ryugu sample. The data further
expanded on the indications from the remote sensing observations that Ryugu is dominated by hydrous carbonaceouschondrite-like materials, similar to CI chondrites, but with an optically darker, more porous, and more fragile nature.
In order to analyze both organic and inorganic matter, the pieces of Ryugu were subject to in-depth investigations in the
Pheasant Memorial Laboratory (PML), Okayama University at Misasa. The 16 particles of Ryugu sample (A0022, A0033,
A0035, A0048, A0073, A0078, and A0085 from the natural surface of the equatorial region of Ryugu, and C0008, C0019,
C0027, C0039, C0047, C0053, C0079, C0081, and C0082 from the surrounding site of the artificial impact crater on Ryugu;
total ~55 mg) were selected during the Phase-1 Curation. The selected samples were then transferred to the ultimate clean
room in the PML for Phase-2 Curation, to catalog the samples via a comprehensive analytical strategy.
The particles were first characterized under digital optical microscope and then their volume and mass were measured
to determine their densities. The average density was 1530 ± 250 kg m-3, which was systematically larger than the value
reported in Yada et al (2021). To elucidate the systematic differences among the 16 pieces, both plainer surfaces and powder
were created from each piece using an ultra-microtome equipped with a diamond knife. The surface was observed using
optical microscope and SEM, the major element distribution and mineral phases were determined by EDS installed in SEM,
micro-Raman spectroscopy, micro-XRD and TEM, all without coating. Subsequently, major and trace element compositions
were determined from a given powder by ICP-MS. Element and isotope compositions of H, C, N and O were determined bygas-source mass-spectrometry, and those of Ne were determined by laser-heating noble-gas-mass-spectrometry using small
broken pieces. Solvent soluble organic matter was extracted from sample powders using various solvents, including water,acetonitrile, ethyl acetate and formic acid. Meanwhile, insoluble organic matter was isolated after solvent extraction anddemineralization by HCl, HF and boric acid. After the first-round characterization, the microtomed surfaces were surveyedusing micro-Raman spectroscopy, SIMS and desorption electrospray ionization-orbitrap-mass spectrometry (DESI-OT-MS).
The 16 pieces were found to consist of magnetite, carbonate, phosphates, sulfides and minor silicate fragmentsinterfiled by matrix (modal abundance of 86-96%) that was dominated by sub-micron-sized phyllosilicates. Average modal
abundances of the aforementioned phases (excluding matrix) were 3.7, 2.4, 0.8, 2.5 and 0.4 %, respectively. The
phyllosilicates were mainly composed of the serpentine and smectite groups. As noted by the Phase-1 Curation, the existenceof high-temperature nebular products, such as refractory inclusions and chondrules were not found. The magnetite was present
as micron-sized euhedral to subhedral grains and sub-micron-sized grains with a framboidal and plaquette texture. Noncarbonate carbon-rich phases of several micrometers in size, were discovered embedded in the matrix (modal abundance is~0.2%). The presence of soluble and insoluble organic matter was confirmed by DESI-OT-MS and FTIR and micro-Raman
spectroscopy, respectively. Further characterization of the solvent soluble fraction via HPLC-OT-MS and GC-MS is currently
underway. The organic matter is ubiquitous in the matrix according to observations by SIMS and micro-Raman spectroscopy.

The major and trace element compositions and O isotope composition are homogenous, with the major and traceelement compositions representing the proto-solar abundance of Lodders (2020). However, a significant variation of H, C, N
and Ne isotopic compositions at the sub-mm scale among the particles was found, which suggests that Ryugu has experienced
a complex evolutionary history.
In this talk, preliminary results from the Misasa Phase2 Curation team will be presented.
References
Kawaguchi, J. et al., The MUSES-C mission for the sample and return—its technology development status and readiness, Acta
Astronautica, 52, 117-123, 2003.
Kitazato, K., et al., The surface composition of asteroid 162173 Ryugu from Hayabusa2 near-infrared spectroscopy, Science
364, 272-275, 2019.
Lodders, K., Relative Atomic Solar System Abundances, Mass Fractions, and Atomic Masses of the Elements and Their
Isotopes, Composition of the Solar Photosphere, and Compositions of the Major Chondritic Meteorite Groups. Space
Science Reviews, 217, 1-33, 2021.
Nakamura, E. et al., Space environment of an asteroid preserved on micrograins returned by the Hayabusa spacecraft,
Proceedings of the National Academy of Sciences of the United States of America, 109, E624-E629, 2012.
Potiszil, K. et al., The Albedo of Ryugu: Evidence for a High Organic Abundance, as Inferred from the Hayabusa2
Touchdown Maneuver, Astrobiology, 20, 916-921, 2020.
Sugita, S. et al., The geomorphology, color, and thermal propertiesof Ryugu: implications for parent-body processes, Science
364, eaaw0422, 2019.
Tsuda, Y. et al., Hayabusa2 mission status: landing, roving and cratering on asteroid Ryugu, Acta Astronautica 171, 2-54,
2020.
Yada, T. et al., Ryugu: A brand-new planetary sample returned from a C-type asteroid, Nature Astronomy, in press, 2021.

The C-type asteroid Ryugu:
A first detailed look by Phase2 Curation Kochi (Ph2K)
M. Ito1, N. Tomioka1, M. Uesugi2, A. Yamaguchi3, N. Imae3, N. Shirai4, T. Ohigashi5, M. Kimura3, M-C. Liu6,
R.C Greenwood7, K. Uesugi2, A. Nakato8, K. Yogata8, H. Yuzawa5, Y. Kodama9*, M. Yasutake2, R. Findlay7, I.A Franchi7,
J.A. Malley7, K. Hirahara10, A. Tsuchiyama11, A. Takeuchi2, I. Sakurai12, I. Okada12, Y. Karouji13, T. Yada8, M. Abe8,
T. Usui8, S. Watanabe12, and Y. Tsuda8.
1
8

JAMSTEC Kochi, 2JASRI/SPring-8, 3NIPR, 4Tokyo Met. Univ., 5UVSOR/IMS, 6UCLA, 7Open Univ.,
JAXA/ISAS, 9MWJ, 10Osaka Univ., 11Ritsumeikan Univ., 12Nagoya Univ., 13JAXA/JSEC, *Toyo Corp.

The Hayabusa2 spacecraft successfully returned to
Figure 1. Largest Ryugu sample (A0002) for the Phase 2 curation
Earth surface materials from the C-type asteroid 162173
Kochi. (a) optical and (b) 3D-reconstruct images
Ryugu on December 6th 2020. The sample capsule contained(a)(b)
a large number of small grains (a few to several mm in size),
collected from touchdown sites 1 and 2 on Ryugu, with a total
mass of ~5.4 g [1, 2]. After initial characterization of thegrains by JAXA curation (e.g., size, weight, FTIR andMicrOMEGA spectroscopic survey), we received eight grains(four from Room A and four from Room C) on June 17, 2021
(Figure 1 and Table 1). Detailed study of the materials
returned from Ryugu will provide critical information about the origin and early evolution of the Solar System and in particular,
the nature of the asteroid-meteorite connection, water-rock interactions on asteroids, the evolution of organics on small bodies,
the diversity and history of asteroid families in the main belt.
On June 19, 2021, we started initial characterization studies of all our samples using synchrotron radiation-based CT
and XRD at the SPring-8. An air-tight sealed carbon nano-tube sample holder was used for CT analysis. In order to avoid
degradation and contamination due to interaction with the terrestrial atmosphere (water vapor and oxygen gas) [3], all of thesample preparation (chipping by a chisel, cutting by a counter balanced diamond wire saw, and epoxy mount preparation) was
conducted in a glove box in an atmosphere of pure, dry N2 (Dew point: -80 to -60˚C, O2 ~50 to 100 ppm). Once we had acquired
high-resolution, detailed three-dimensional structural and crystallographic information (0.85 µm/pixel for CT) for each of oursamples, we were able to define a priority list for the next phase of the analytical campaign, which involved coordinated micro
and bulk analysis.
The micro-analysis plan proposed by Ph2K involves the use of a wide range of multi-beam instruments to acquiredetailed micro-textural and chemical information about the samples at a sub-micrometer scale. Ongoing studies have involved
the use of FIB, STXM-NEXAFS, NanoSIMS and TEM [4]. In parallel, we are conducting bulk analysis of the samples using
SEM-EDS, EPMA, Raman spectroscopy, XRD, large geometry type SIMS, high precision O isotopic analysis by laser
fluorination and INAA. We have used air-tight containers (a facility-to-facility transfer container, FFTC [4]) for sample
transportation to nation-wide institutes by hand carry. With the assistance UK embassy in Tokyo, a few representative grains
were delivered to the Open University without any potentially invasive inspection (i.e., X-ray).
In this talk, we will present the preliminary results of the Ph2K coordinated micro-analysis and systematic bulk chemical
analysis campaign, which is focused on providing a detailed understanding of these precious Ryugu returned samples.
References: [1] Morota T. et al. 2020. Science 368, 654–659. [2] Yada et al. 2021. Abstract#2008, 52nd LPSC. [3] Uesugi M.
et al. 2020. Rev. Sci. Instrum. 91, 035107. [4] Ito M. et al., 2020. Earth, Planets and Space 72, 133.
Table 1. The Ryugu samples for the Phase2 curation Kochi
Sample No.

mgµm

SPring-8

Microanalysis(STXM, NanoSIMS, TEM)

Bulk Analysis(SEM-EDS, EPMA, Raman)

A0002

19.3

4,092

HR-CT, XRD, XRD-CT

Y

A0029

9.1

3,069

HR-CT, XRD, XRD-CT

Y

Y

A0037

7.8

3,129

HR-CT, XRD, Phase-contrast CT

Y

Y

A0098

1.9

1,868

HR-CT

C0009

11.1

3,520

HR-CT, XRD, XRD-CT

C0014

6.8

3,527

HR-CT

C0068

1.68

1,980

HR-CT

C0087

2

3.242

HR-CT

High Precision
O isotopes

SIMS

Y

XRD

Y
Y
Y

Y

INAA

Y

Y

Y

Y

Y

Y
Y

Y

Y

Y

Y
Y

Y
Y

JAXA Detailed Description -Variation of surface characteristics of Ryugu returned samplesAiko Nakato1, Toru Yada1, Kasumi Yogata1, Akiko Miyazaki1, Kentaro Hatakeda1,2, Kazuya Kumagai1,2, Masahiro
Nishimura1, Yuya Hitomi1,2, Hiromichi Soejima1,2, Kana Nagashima1, Jean-Pierre Bibring3, Cedric Pilorget3, Vincent Hamm3,
Rosario Brunetto3, Lucie Riu3, Lionel Lourit3, Damien Loizeau3, Tania Le Pivert-Jolivet3, Guillaume Lequertier3, Aurelie
Moussi-Soffys4, Masanao Abe1, Tatsuaki Okada1 and Tomohiro Usui1
1
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 2Marine Works Japan, Ltd., 3Institutd'Astrophysique Spatiale, Université Paris-Saclay, CNRS, 4Centre National d'Etudes Spatiales
The Ryugu sample brought back by the Hayabusa2 spacecraft in December 2020 weighed ~5.4 g, which is much larger
than we expected [1, 2]. After the samples were delivered to JAXA Extraterrestrial Curation Center, individual grains have been
picked up and stored into sapphire dish, and analyzed by optical microscope, weighting, FTIR spectroscopy, and MicrOmega
hyperspectral imaging [3] for initial description [2]. The obtained data will open in early 2022 for International Announcementof Opportunity (AO) through curatorial Database System for Ryugu Sample [4]. During the ffirst 6 months, we observed 205
individual grains, 100 from chamber A and 105 from chamber C. There are some unique characteristic features on the surface.
Here, we propose a morphological classification of these surface features into 4 groups, based on visible characteristics of Ryugu
samples. 1/ Dark and fluffy: these features are dominant in Ryugu samples; 2/ Dark and glossy: they are present either on a partor on the entire of grain; 3/ Bright: also present either on a part or on the entire of grain; 4/ White regions: they are observed over
300 μm in size. Those characteristics may be observed alone or in duplicate on a single grain.
In July 2021, 4 grains showing those different features, were allocated as JAXA detailed description (JAXA-DD) (Fig.1). We
conduct petrological and mineralogical observation by SEM and XRD to understand the linkage with surface characteristics
obtained by the initial description. The purpose of this study is to contribute to the sample selection by researchers at Int’l AO.
FE-SEM/EDS observation was performed using Hitachi SU6600 equipped with slow purge system in order to non-airexposure transportation from glove box to SEM, on the front surface where the main initial description was made. For two
grains A0017 and C0094, where the entire front surface shows unique characteristics, SEM observation was also performed on
the back surface. After these observations, we performed a sample chipping under pure N2 atmosphere inside Glove Box. A
specially developed tantalum chisel is used for the division. Since tantalum is also used as a bullet when collecting samples on
the asteroid, it was selected as materials for the purpose of unifying the potential sources of sample contamination. From thedivided sample, we separated small portions showing each of the four characteristics and we performed additional SEM
observations. We handled the samples under non-air-exposure environment until the sample division. The small portions areattached to carbon fiber with glue for future XRD analysis using RIGAKU RA-Micro7 HFMR.
In this presentation, we will introduce the variations of Ryugu sample surface characteristics, reflecting variations of theirmineralogy and petrography, coordinated with JAXA initial description.

A0042

C0094

A0017

C0041

Figure 1. Optical microscopic images of 4 grains allocated to JAXA-DD.
a) A0042：Dark and fluffy feature is dominant in Ryugu samples. b) C0094: Dark and glossy characteristic is appeared on entire surface.
c) A0017: Bright area cover most of the front surface. d) C0041: White region is shown at the right bottom and left top of grain.

References: [1] Tachibana S. et al. (2021) LPS, XXXXXII, Abstract #1289. [2] Yada T. et al. (2021) LPS, XXXXXII,
Abstract #2008. [3] Bibring J.-P. et al (2017) Space Sci. Rev. 208, 401-412. [4] Nishimura M. et al. (2021), Astromaterials
Data Management in the Era of Sample-Return Missions Community Workshop, Abstract.

Overview of the features of returned samples from the C-type asteroid 162173 Ryugu
based on optical microscope observations and their weights
A. Miyazaki1, T. Yada1, M. Abe1,2, A. Nakato1, K. Yogata1, K. Nagashima1,
K Hatakeda1,4, K. Kumagai1,4, M. Nishimura1, Y. Hitomi1,4, H. Soejima1,4, M. Yoshitake1, A. Iwamae1,4,S. Furuya1,3, K. Sakamoto1, T. Okada1,3, S. Tachibana1,3, H. Yurimoto1,5, T. Usui1
1
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency,
2
The Graduate University for Advanced Studies (SOKENDAI) ,3University of Tokyo,
4
Marine Works Japan, Ltd.,5Hokkaido University.
Hayabusa2 collected the surface and sub-surface material from the C-type near-Earth asteroid 162173 Ryugu and brought back
5.4 g of samples in total to the Earth [1]. The samples were collected during the two touch-down operations: the samples collected
for the first touch-down (TD1) were stored in the Chamber A of the sample catcher, and those collected for the second touchdown (TD2), which was done near the artificial crater made by the SCI [2], were stored in the Chamber C [3]. In the cleanchamber dedicated to Hayabusa2 samples [4], the samples in the Chambers A and C were first put in individual sapphire
containers for the initial characterization of bulk properties. The samples were first observed with an optical microscope and it
was found that the samples from both chambers were aggregation of black-colored mm-sized pebbles and sub-mm sized fine
powder, with millimeter-scale particles being the most common [5]. A few centimeter-sized pebbles were also found in thesamples recovered from the Chamber C [1]. Then, weight analysis, optical spectroscopy and visual multispectral imaging were
performed for the initial characterization. We will present here the features of the individual returned samples based on the
microscopic observations and weight analyses.
Pebbles of 1–10 mm in size were removed from the sapphire containers to individual small sapphire dishes. For the first six
months after the sample receipt, 100 pebbles from the Chamber A and 105 from the Chamber C were hand-picked one-by-one
with vacuum tweezers in the clean chamber under ultra-purified nitrogen atmosphere without exposing to terrestrial atmosphere[6]. The samples in the sapphire dishes are first photographed with an optical stereomicroscope equipped above the cleanchamber through a glass window. The size of the individual samples is measured from the microscopic images. Then, the grossweight of the sample and the sapphire dish in the stainless steel capsule was measured with a microbalance equipped in the CC.
The weight of an individual sample inside the dish is calculated based on the gross weight of the dish in the stainless steel capsule
which was measured in advance.
The preliminary results were reported in [3] and [5]. The observed Ryugu samples have dark spectral features. Many bright andpatchy fine inclusions are observed on the surface of some pebbles, but no apparent high temperature components like chondrules
nor Calcium-Aluminum-rich-Inclusions (CAI) has been observed with optical microscope analyses [5]. These pebbles show
significant morphological variations; grains with rugged surface and with smooth surfaces are observed [3]. These two types offeatures were also found on the surface textures on Ryugu boulders [7]. Many pebbles are also found to feature curved andstraight cracks and some pebbles show elongated block-like morphologies [3]. Densities of individual grains are estimated fromthe grain weight and the volume of approximated spheroid evaluated from the optical observation, leading to the average densityof 1282 ± 231 kg m-3. This density is much lower than the typical grain density of CI chondrites [5]. We will present moredetailed features of the returned individual samples.
References[1] Yada T et al., 2021. 52nd LPSC, abstract#2008. [2] Arakawa M. et al. 2020, Science 368:67. [3] Tachibana S. et al. Submitted
to Science. [4] Abe M. et al., 2021. This meeting. [5] Yada T. et al. Submitted to Nature Astronomy. [6] Yada T. et al., 2014.
Meteoritics Planet. Sci. 49:135. [7] Cho Y. et al., Submitted to Planet. Space Sci.

Initial description of Ryugu returned samples: characteristics of individual grains by FT-IR
analysis
Kentaro Hatakeda1,4, Toru Yada1, Masanao Abe1,2, Tatsuaki Okada1,3, Aiko Nakato1, Kasumi Yogata1, Akiko Miyazaki1,
Kazuya Kumagai1,4, Masahiro Nishimura1, Yuya Hitomi1,4, Hiromichi Soejima1,4, Kana Nagashima1, Miwa Yoshitake1, Ayako
Iwamae1,4, Shizuho Furuya1,3, Tomohiro Usui1, Shogo Tachibana1,3, Kanako Sakamoto1, Kohei Kitazato5, Hisayoshi Yurimoto6
1
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara 252-5210, Japan,
2
The Graduate University for Advanced Studies (SOKENDAI), Hayama 240-0193, Japan
3
University of Tokyo, Bunkyo, Tokyo 113-0033, Japan,
4
Marine Works Japan, Ltd., Yokosuka 237-0063, Japan,
5
The University of Aizu, Aizu-Wakamatsu 965-8580, Japan,
6
Hokkaido University, Sapporo 060-0810, Japan.
A total of ~5.4 g of sample was collected at the surface of the C-type asteroid 162173 Ryugu and successfully returned to
Earth [1] [2]. The collected samples were transported to the curation facility in ISAS, Sagamihara, Japan, and stored in purified
nitrogen condition, except for a few grains picked up under vacuum condition, to keep the samples as physically and chemicallypristine as possible. Approximately 100 grains have been picked up from each of those in Chamber A, uppermost centimeterscale layer of Ryugu collected during the first touch-down sampling (TD1), and in Chamber C, surface to subsurface layer (~1m) of Ryugu collected close to the artificial crater during the second touch-down sampling (TD2). Then, initial descriptions,such as weighing, optical imaging, FT-IR spectroscopy in 1-5 µm range, MicrOmega as a hyperspectral NIR microscope, andvisual multispectral imaging, have been performed for characterization of these samples. Here we present the preliminary resultof FT-IR spectral analysis for individual grains.
The measurement system consists of the spectrometric unit outside the clean chamber and the sample chamber connectedto the clean chamber (Figure 1). Although purified nitrogen gas flowed inside the spectrometric unit, absorption bands of O-H(e.g., H2O) and that of C-O (CO2) appeared in the reflectance spectra of reference material (Infragold) measured after the sample
analysis, indicating the influence of spectral absorption in the atmosphere. In addition, the spot size of the incident beam, approx.
1 mm in diameter at the focal position, was slightly larger than the sizes of individual grains in many cases, and these data were
contaminated by the reflectance from the sapphire dish at the bottom of the sample holder. The reflection from the sapphire dishincreased the albedo, changed the spectral slope between 1 and 2.5 µm from positive to negative, and decreased the absorption
band depth (Figure 2).
Except for the samples with significant effect of sapphire dish, reflectance spectra of individual grains generally show asimilar trend to those of bulk samples [3] in the wavelength range between 2.5 and 4 µm. The depth of absorption bands varied
between grains, and the band-depth variation is observed not only between the individual grains but also within the single grain.
We also found grains with unique spectral profiles, of which abundance is ~1% or less. These grains basically contain relatively
large inclusions, which are apparently different from the surrounding matrix.
We are now planning to modify the FT-IR system to extend to the mid to far-infrared wavelength range, and expect to getfurther information on the collected Ryugu samples.

Figure 1. Overview of the FT-IR measurement system

Figure 2. The mixing effect of the sapphire dish reflectance. The larger effect was observed with increasing the area where incident
beam illuminated the sapphire dish; A) Reflectance spectra (%), B) Normalized reflectance at 2.6 µm, C) Normalized reflectancewith continuum at 2.6-3.2 µm and NIRS3 spectral data [4], D) Normalized reflectance with continuum at 3.3-3.6 µm.

References[1] Tachibana S. et al. (2021) LPS, XXXXXII, Abstract #1289. [2] Yada T. et al. (2021) LPS, XXXXXII, Abstract #2008.
[3] Yada T. et al. in press. Nature Astronomy. [4] Kitazato et al. (2019) Science 364: 272.

MicrOmega detections of C-rich phases in Ryugu returned samples within the Hayabusa2 JAXA
Extraterrestrial Curation Center
Bibring1, J.-P.; Brunetto1, R.; Carter1, J,; Gondet1, B.; Pilorget1, C.; Hamm1, V.; Hatakeda2, K; Langevin1, Y.; Lantz1, C., Le
Pivert-Jolivet1, T.; Loizeau1, D.; Nakato2, A.; Okada2, T.; Riu1,2, L.; Usui2, T.; Yada2, T.; Yogata2, K., 1Institutd'Astrophysique Spatiale, Université Paris-Saclay, CNRS, 2Institute of Space and Astronautical Science, Japan Aerospace
Exploration Agency
The Ryugu samples brought back by the Hayabusa2 spacecraft in December 2020 have been delivered to the JAXA
Extraterrestrial Curation Center [1, 2]. Bulk samples and then individual grains have been deposited onto sapphire dishes,
weighted, and analyzed with optical microscopy, FTIR spectroscopy, and MicrOmega hyperspectral imaging [3] for initialdescription [2]. The MicrOmega instrument used in the JAXA Extraterrestrial Curation Center is a NIR hyperspectral
microscope. It images samples ~ 5 mm x 5 mm large, with 250x256 pixels of ~22 µm in size. Its spectral capability covers therange from 0.98 µm to ~3.6 µm, which gives access to primary and secondary minerals and organic matter, in particular throughtheir OH, CO3, and CH features [4, 5].
As presented in the Yada et al. and Pilorget et al. talks (this conference), the averaged spectra of Ryugu returned samples present
two major features, centered around 2.7 and 3.4 µm, attributed to OH-rich and CH-rich compounds respectively. Thanks to the
MicrOmega capability to characterize the spectral signatures of returned grains down to the few tens of µm scale, a variety of
C-rich compositions do show up, through the following features:- variability in the central position and shape of the 3.4 µm dominant absorption, with a minimum varying from 3.35 µm to 3.45
µm, and the occasional presence of several local minima with varying spectral band areas. These observations suggest organic
matter of varying composition and structure is present over the entire samples;- the presence of coupled spectral features such as at around 2.85 µm, 3.1 µm or 3.55 µm, with their associated band ratios.
Additional spectral structures < 2.7 µm are in some cases observed and correlate with them. These bands collectively suggest
organic carbon is at times bound to non-C groups or intimately mixed with specific minerals.
- the ratio between the 2.7 µm and 3.4 µm band depths spans a very wide range of values, with some grains highly depleted ineither OH-rich or CH-rich phases.
These spectral features are diagnostic of specific C-rich compositions and of their spatial heterogeneity in the collected samples
at the scale of few tens to few hundred microns. We shall present a preliminary review of the observed diversity, and discuss itin terms of the composition and origin of the potential carriers.

References[1] Tachibana S. et al. (2021) LPS, XXXXXII, Abstract #1289. [2] Yada T. et al. (2021) LPS, XXXXXII, Abstract #2008. [3]Bibring J.-P. et al (2017) Space Sci. Rev. 208, 401-412. [4] Pilorget C. and Bibring J.-P. (2014) PSS 99, 7-18. [5] Pilorget C. et
al. (2021) this conference.

MicrOmega detections of carbonates in Ryugu returned samples within the Hayabusa 2 JAXA
Extraterrestrial Curation Center
Loizeau, D.1; Bibring, J.-P.1; Brunetto, R.1; Pilorget, C.1; Okada, T.2,3; Carter, J.1;Gondet, B.1; Hamm, V.1; Hatakeda, K.2,4;
Langevin, Y.1; Lantz, C.1; Le Pivert-Jolivet, T.1; Nakato, A.2; Riu, L.2; Usui, T.2,3; Yada, T.2; and Yogata, K.2;
1
Institut d'Astrophysique Spatiale, Université Paris-Saclay, CNRS, France
2
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Japan 3University of Tokyo,
Bunkyo, Japan, 4Marine Works Japan, Ltd., JapanThe Ryugu samples brought back by the Hayabusa2 spacecraft in December 2020 have been delivered to the JAXA
Extraterrestrial Curation Center [1, 2]. Bulk samples and then individual grains have been picked up and stored into sapphire
dishes, weighted, and analyzed with an optical microscope, FTIR spectroscopy, and MicrOmega hyperspectral imaging [3] for
initial description [2]. The MicrOmega instrument used in the JAXA Extraterrestrial Curation Center is a NIR hyperspectral
microscope. It has a total field of view of 5 mm x 5 mm, with resolution of ~22 µm/pixel in the focal plane. It covers the
spectral domain from 0.99 µm to ~3.6 µm. Its capabilities enable the identification of organic matter and of different minerals
in the returned samples [4]. Initial analyses with MicrOmega were first made on the bulk samples from chambers A and C of
the Hayabusa 2 returned capsule, and then on individual grains stored in their sapphire dishes. 137 out of the 205 extracted
grains have been analyzed with MicrOmega as of September 30, 2021 [5].
In the spectral domain of MicrOmega, carbonates have a strong characteristic double absorption band in the 3.3-3.5 µm area,accompanied by two other weaker bands around 2.5 and 2.3 µm. The exact spectral position of these bands varies with thecation content of the carbonate [6]. Iron-bearing carbonates also show a strong absorption below 1.5 µm.
First detections of carbonates were made in grains included in the bulk samples from both chambers A and C. Some small
grains seem to be entirely carbonate-rich and are up to ~450 µm, down to <50 µm in size. Carbonate inclusions were also
detected in larger grains, with sizes up to ~380 µm in a >1.5 mm-sized grain, and down to <50 µm (figure 1-A).
From the first 130 analyzed extracted grains, MicrOmega detected carbonate inclusions with high confidence in 19 of thosegrains. The largest detection was made on grain C0041, covering ~0.25 mm , or ~10% of the visible surface of the grain(figure 1-B). This grain is one of the grains with “White regions” as described in Nakato et al. [7].
In terms of spectral characteristics, they all present a double band at 3.31-3.47 µm and a band centered at 2.71 µm. The largest
grains and inclusions also exhibit spectral bands at 2.51 and 2.30 µm, also characteristic of carbonates, and a deep absorption
below 1.5 µm. Some detections also have a band at 2.77 µm (present in many carbonate reference spectra), and some between
3.07 and 3.10 µm. The presence of a strong absorption below 1.5 µm indicates the likely presence of Fe2+ in the carbonate
mineral, although the position of the bands around 2.3, 2.5 and 3.4 µm is shifted to shorter wavelength compared to a purely
Fe2+ carbonate (siderite), and would better fit Mg-bearing carbonates like dolomite or magnesite. The iron-bearing magnesite
breunnerite is a likely candidate for these detections. Smaller grains and inclusions do not show the absorption below 1.5 µm,
while the other absorptions are centered around the same positions than for the larger grains (figure 1-C). Likely candidates
include dolomite and magnesite.
Such carbonate grains and inclusions within the returned samples from Ryugu are a key to understand the evolution of theasteroid. MicrOmega can help mapping and quantifying the presence of these carbonates throughout the collection.

Figure 1. Example of carbonate detections with MicrOmega on bulks from chamber A and C, and on an extracted grain from chamber C.
Left: MicrOmega images with red pixels where carbonate is detected. A: extracted grain C0041. B: bulk samples from chamber A. C: bulk
samples from chamber C. Right: Average spectra of pixels with carbonate detections within the colored boxes in the left images.

References[1] Tachibana S. et al. (2021) LPS, XXXXXII, Abstract #1289. [2] Yada T. et al. (2021) LPS, XXXXXII, Abstract #2008. [3]Bibring J.-P. et al (2017) Space Sci. Rev. 208, 401-412. [4] Pilorget C. and Bibring J.-P. (2014) PSS 99, 7-18. [5] Pilorget C. et
al. (2021) this conference. [6] Hunt G.R. and Salisbury J.W. (1971) Visible and near infrared spectra of minerals and rocks. II.
Carbonates. Modern Geology 2, 23–30. [7] Nakato A. et al. (2021) this conference.

The 2.7µm OH band in different grains of Ryugu from the two collection sites, as seen by
MicrOmega in the Hayabusa2 Curation Facility
Tania Le Pivert-Jolivet1, Jean-Pierre Bibring1, Rosario Brunetto1, Cedric Pilorget1, Tatsuaki Okada2, John Carter1, Brigitte
Gondet1, Vincent Hamm1, Kentaro Hatakeda2,3, Yves Langevin1, Cateline Lantz1, Damien Loizeau1, Aiko Nakato2, Lucie
Riu1,2, Tomohiro Usui2, Toru Yada2 and Kasumi Yogata2
1

IAS, Université Paris-Saclay, CNRS, France, 2Institute of Space and Astronautical Science, Japan Aerospace Exploration
Agency, 3Marine Works Japan, Ltd

Hayabusa2 is the first space mission to study and collect samples from a C-type asteroid. In December 2020, thespacecraft brought back to Earth ~5.4g of materials from the surface of asteroid (162173) Ryugu. The samples were collectedfrom two different sites TD1 and TD2 [1] at the surface of the asteroid, possibly sampling surface and subsurface materials. The
samples were delivered to JAXA (Japan Aerospace eXploration Agency) Extraterrestrial Curation Center for preliminary
analyses. Individual grains were extracted and analyzed in a controlled N2 environment by an optical microscope, a FTIR
microscope and MicrOmega, a near-infrared (0.99-3.65 µm) hyperspectral microscope. MicrOmega acquires images of 256x250
pixels with a spatial resolution of 22.5 µm. The total field of view covers ~5x5mm [2].
In addition to the bulk samples, observations of individual grains, extracted from the bulks, were performed with
MicrOmega at different azimuth angles to optimize the coverage and avoid potential photometric biases. In order to extract
average spectra of the individual grains (typical size 1-4.5 mm), we developed a novel procedure using thermal emission maps
measured by MicrOmega: first the grains were isolated from the rest of the field of view (the sample holder) thanks to theirdifference in terms of thermal emission, then their pixels were averaged at each azimuth orientation. Spectral parameters were
finally calculated to characterize the position and the depth of the 2.7 µm OH feature. This band is believed to be related to thepresence of metal-OH stretching modes in phyllosilicates [3], and it is observed at large scale over the surface of Ryugu [4].
We shall present the distribution of the spectral parameters of the 2.7 µm feature observed by MicrOmega on grains
extracted from chamber A and chamber C, corresponding to TD1 and TD2 respectively. We will discuss the potential variationsof the spectral parameters, in particular with regards to the observations performed at a much larger scale by NIRS3, and their
possible implications regarding the hydrothermal and space weathering history of the asteroid.
References[1] Tachibana et al. (2020) LPS XXXXXI Abstract #2027. [2] Bibring et al. (2017) Space Sci. Rev. 208, 401-412. [3]Madejová et al. (2017) Developments in Clay Science, 8, 107-149. [4] Kitazato et al. (2019) Science, 364, 272-275

Microscale Diversity of H, C, and N Isotopes in Asteroid Ryugu
Larry R. Nittler1, Jens Barosch1, Bradley T. De Gregorio2, Rhonda M. Stroud2, Hikaru Yabuta3, and The Hayabusa2initial-analysis IOM team, Hisayoshi Yurimoto4, Tomoki Nakamura5, Takaaki Noguchi6, Ryuji Okazaki7, Hiroshi
Naraoka7, Kanako Sakamoto8, Shogo Tachibana8,9, Sei-ichiro Watanabe10 and Yuichi Tsuda8
1Carnegie Institution of Washington, Washington DC, USA, 2US Naval Research Laboratory, Washington DC, USA,
3
Hiroshima Univ., 4Hokkaido Univ., 5Tohoku Univ., 6Kyoto Univ., 7Kyushu Univ., 8JAXA, 9Univ. of Tokyo, 10Nagoya
Univ.
Understanding the nature and origin of organic matter in asteroid 162173 Ryugu is one of the key science goalsof the Hayabusa2 sample-return mission. Macromolecular organic matter (MOM) makes up to a few % of primitive
meteorites and displays a wide range of H, C, and N isotopic ratios on whole-rock to sub-µm scales [1]. Both its origin(for example, whether in the protosolar molecular cloud or in the protoplanetary disk) and the degree to which it ismodified on asteroidal parent bodies is debated, but it may represent the dominant form of C delivered to early Earth.
NanoSIMS-based isotopic imaging surveys of both bulk CI, CR, CM, and CO chondrites and purified MOM residues
from them [2-6] have revealed that, while bulk samples are typically modestly enriched in D and 15N, relative to the
Earth, a small fraction of the material shows much more extreme enrichments and/or depletions in these isotopes.
Large 13C enrichments and depletions are also seen in chondrites, both in presolar circumstellar SiC and graphite
grains [7], and in rare cases in MOM particles [8].
We have begun conducting similar NanoSIMS surveys of Ryugu samples. Four grains from Chamber A
aggregates (A0108) were embedded in S and sectioned with an ultramicrotome equipped with a diamond knife.
Relatively thick (250-nm) slices were deposited onto Si wafers for NanoSIMS analysis while adjacent thin sections
were kept for coordinated analysis by transmission electron microscopy (TEM) and synchrotron X-ray microscopy(STXM). After the S was sublimated, we applied a thin Au coat to the Si wafers and analyzed them with a NanoSIMS
50L ion microprobe in multicollection imaging mode. Microtome sections were first analyzed for C and N isotopes(as 12C2, 12C13C, 12C14N, and 12C15N, plus 16O, 28Si, MgO and secondary electrons) with a 0.4 pA, <200-nm Cs+ beam.
The sections were then re-analyzed at the same magnification with a 1-pA beam and collection of 1H, D, and 12C
secondary ions and secondary electrons. Five of the sections were subsequently re-measured for C and N to improvethe counting statistics. Total counting times varied but were typically of order ~0.1 s/0.01 µm2 for each run.
The measurements reveal broadly similar results to similar data obtained on primitive carbonaceous chondrites.
The four particles show modest bulk enrichments of D and 15N, with D/H and 15N/14N ratios in general agreement withthose of CI chondrites. The NanoSIMS images show that much of the C is present as particles typically a few hundred
nm in size, but ranging up to 2 µm. As in chondrites, a fraction of these particles show more extreme enrichments ordepletions (“hotspots” and “coldspots”) which span ranges similar to those recently seen in the least-altered CM
chondrites Asuka 12169, Asuka 12236, and Paris [3]. A much smaller fraction of C-rich grains shows 13C anomalies,
associated both with presolar grains and organic particles. The bulk and microscale isotopic distributions vary to someextent among the four Ryugu grains, indicating heterogeneity at the 100-µm scale. Planned TEM and STXM
measurements of slices from the same grains will help unravel the chemical nature of the organic particles and theirrelationship to inorganic phases in the asteroid.
References[1] Alexander C. M. O’D. et al. 2017. Chemie der Erde - Geochemistry 77:227. [2] Busemann H. et al. 2006.
Science 312:727. [3] Nittler L. R. et al. 2021. Abstract #6063. 84th Meteoritical Society Meeting. [4] Remusat L. et
al. 2010. The Astrophysical Journal 713:1048. [5] Nittler L. R. et al. 2019. Nature Astronomy 3:659. [6] Nittler L.
R. et al. 2018. Geochimica et Cosmochimica Acta 226:107. [7] Zinner E., 1.4 - Presolar grains, in: A.M. Davis(Ed.), Meteorites and Cosmochemical Processes (Vol. 1), Treatise on Geochemistry (Second Edition, eds: H. D.

Holland and K. K. Turekian), Elsevier-Pergamon, Oxford, 2014, pp. 181–213. [8] Floss C. et al. 2009. AstrophysicalJournal 697:1242.

Diversity of Insoluble Organic Matter at the Nanoscale in Asteroid Ryugu
Rhonda M. Stroud1, Bradley T. De Gregorio1, Larry R. Nittler2, Jens Barosch2, Hikaru Yabuta3, and The Hayabusa2initial-analysis IOM team, Hisayoshi Yurimoto4, Tomoki Nakamura5, Takaaki Noguchi6, Ryuji Okazaki7, Hiroshi
Naraoka7, Kanako Sakamoto8, Shogo Tachibana8,9, Sei-ichiro Watanabe10 and Yuichi Tsuda8
1
US Naval Research Laboratory, Washington DC, USA, 2Carnegie Institution of Washington, Washington DC, USA,
3
Hiroshima Univ., 4Hokkaido Univ., 5Tohoku Univ., 6Kyoto Univ., 7Kyushu Univ., 8JAXA, 9Univ. of Tokyo, 10Nagoya
Univ.
Acid-insoluble, macromolecular organic matter represents up to 4 wt% of the matrix of carbonaceous chondrites(CC). Many properties of the insoluble organic matter (IOM), including microstructure, functional group chemistry,
and mineralogical associations strongly correlate with asteroid parent body grouping and alteration history [1].
However, the IOM of many chondrites shows significant variation in structure, chemistry, and isotopic compositionat the nanoscale [2,3]. The microstructure of CC IOM ranges from discrete sub-micron blebs called nanoglobules; tomicrometer and larger sized veins; diffuse intergranular material; OM intercalated into phyllosilicates, and poorlygraphitized carbonaceous grain coatings. In addition, the IOM can serve as host to inorganic carbonaceous phases,
such as presolar nanodiamond [4] and phase-Q [5]. This variation results from a combination of inherited molecular
cloud chemistry, nebular processing, parent body and terrestrial alteration. Studies of the nanoscale variation in the
IOM in the returned samples of Ryugu provide the first chance to examine the IOM of a CC parent body largely freeof terrestrial alteration signatures, in order to better constrain the alteration history of a specific asteroid, and provide
unprecedented constraint on the evolution of carbon in the early solar system.
Our primary method for the Initial Analysis of the nanoscale diversity of Ryugu IOM microstructure andfunctional chemistry is scanning transmission electron microscopy (STEM), in coordination with scanningtransmission x-ray absorption spectroscopy (STXM), and isotopic characterization with NanoSIMS. The STEM
measurements are carried out with the Nion UltraSTEM 200-X at the Naval Research Lab, operated at 60 kV tominimize electron beam damage. STEM measurements include annular dark field (ADF) imaging, electron energy
loss spectroscopy (EELS), and energy dispersive x-ray spectroscopy (EDS). The EELS and EDS data are collected
as simultaneous spectrum images to allow direct correlation of the elemental composition with the C functional
chemistry, and microstructure [6]. As of this abstract submission, we have examined slices of three grains from
Chamber A (A0108), one prepared as a focused ion beam (FIB) lift-out section, and two prepared as sulfur-embedded
ultramicrotome slices. The FIB section was analyzed with STXM at Photon Factory Bl-19 prior to the STEM analysis.
Adjacent microtome slices of were prepared for coordinated STXM and NanoSIMS measurements at the Advanced
Light Source and Carnegie Institution of Washington, respectively. Measurements of additional FIB and microtome
slices of Chamber A and Chamber C particles are planned.
Overall, our STEM measurements indicate IOM microstructures and functional chemistry consistent with low
temperature aqueous alteration, broadly consistent with CI and CM chondrites. Small nanoglobules (< 400 nm) areabundant, but larger nanoglobules > 1000 nm are less common. Diffuse carbon intercalated into phyllosilicates is also
common. Carbonate and nanoscale Fe, Ni sulfides are also found in association with IOM Coordination of the STEM
results with the ongoing STXM and NanoSIMS measurements of slices from the same grains will ultimately help
constrain the nature of Ryugu and its relationship to known carbonaceous chondrites, and the history of the organic
matter it contains.
References[1] Alexander C. M. O’D. et al. 2017. Chemie der Erde - Geochemistry 77:227. [2] De Gregorio B. T. et al. 2013.
Meteoritics & Planetary Science 48:904. [3] C. Le Guillou et al. 2014. Geochemica et Cosmochemica Acta 131:368. [4] Garvie, L.A.J. (2010), Lunar and Planetary Science Conference, #1388. [5] Amari, S., et al. 2013.
Astrophysical Journal 778:37. [6] Stroud R. M. et al. Microscopy and Microanalysis 27(S1):2546.

Infrared transmission spectra of Ryugu particles and their unique adsorption behavior
Yoko Kebukawa1, Lydie Bonal2, Eric Quirico2, Emmanuel Dartois3, Cécile Engrand4, Jean Duprat5, Jérémie Mathurin6,
Alexandre Dazzi6, Ariane Deniset-Besseau6, Hikaru Yabuta7 and The Hayabusa2-initial-analysis IOM team,
Hisayoshi Yurimoto8, Tomoki Nakamura9, Takaaki Noguchi10, Ryuji Okazaki11, Hiroshi Naraoka11, Kanako Sakamoto12,
Shogo Tachibana12,13, Sei-ichiro Watanabe14 and Yuichi Tsuda12
1
Yokohama National Uni., 2IPAG, Univ. Grenoble Alpes, CNRS CNES 3ISOM, 4IJCLab, 5IMPMC/MNHN, 6ICP, 7Hiroshima
Univ., 8Hokkaido Univ., 9Tohoku Univ., 10Kyoto Univ., 11Kyushu Univ., 12JAXA, 13Univ. of Tokyo, 14Nagoya Univ.
The Hayabusa2 spacecraft successfully obtained samples from two different locations from Ryugu, a C-type asteroid, andreturned them to the Earth on December 6, 2020. The first touchdown samples and second touchdown samples were separately
stored in sample container chamber A and chamber C, respectively. The initial analyses began in June 2021, after curation at
ISAS/JAXA. The insoluble organic matter (IOM) subteam has so far conducted in-situ analyses of the Ryugu particles, inorder to decipher the nature of the organic matter and its origin, parent body processing, and interaction with water andminerals. Fourier transform infrared (FTIR) spectroscopy is a nondestructive technique for functional group chemistry andstructures which is suitable for both organic and inorganic compounds. To date, IR absorption (transmission) spectra have beenobtained from various chondrites and other astromaterials such as interplanetary dust particles (IDPs), micrometeorites andcometary dust particles [e.g., 1-7]. IR spectroscopy is often employed for astronomical observations and remote sensing. The
reflectance spectra of solar system bodies provide information of the compositions of their surfaces. To compare the laboratory
samples and the surfaces of asteroids, IR reflectance spectra have been commonly used [e.g., 8-10]. Both IR transmission andreflectance spectra give intrinsically similar information as both reflect the absorptions of IR frequencies by the target samples,
although some differences do exist. As a part of the initial analysis in the IOM team, IR absorption spectra were obtained using
FTIR microspectroscopy, to provide initial characterization of the Ryugu particles and search for organic matter, as well as forcomparison with the surface reflectance spectra of Ryugu. Several samples were analyzed in parallel in the team, in Japan(Yokohama National Univ., YNU) and in France (IPAG, Grenoble and Orsay-lab teams) to increase the robustness of theanalysis.
Each particle (sub-millimeter in diameter) from the aggregates in chamber A (A0108) or chamber C (C0109), was further
decomposed by gently crushing between two glass slides, or by separation of a fragment with a scalpel. The small fragments
were then further crushed between two diamond windows (YNU and IPAG) and in a diamond compression cell under an
optical microscope to optimize the thickness for further atomic force microscope based infrared spectroscopy (AFM-IR)
measurements (Orsay-lab). In YNU, IR absorption spectra were collected from each diamond window with a micro-FTIR(JASCO FT/IR-6100+IRT-5200), equipped with a ceramic IR light source, a germanium-coated KBr beam splitter, a mercurycadmium-telluride (MCT) detector, and ×16 Cassegrain mirrors, with typically 20 × 20 μm aperture. The microscope and the
FTIR were continuously purged with dry N2. To remove adsorbed water further from the sample, a heating stage (Linkam
10036L) was employed. The IR absorptions from water were satisfactory removed typically by 60 °C under N2 flow. MicroFTIR measurements were also conducted at IPAG with a Hyperion 3000 Bruker FTIR microscope, operating with a ~50 × 50
µm spot and an environmental cell placing the sample under secondary vacuum (< 10 -6 mbar) and gentle heating (< 80° C) toremove adsorbed water. IR spectra by the Orsay-lab team were taken during a week of beamtime at the SOLEIL synchrotron(SMIS beam line). The synchrotron beam was coupled to a Nicolet Continuum 2 IR microscope equipped with a MCT detector
and a ×32 Cassegrain optics, under dry air. For these measurements, the IR spot size was optimized with an aperture of 6 × 6µm, close to the diffraction limit, and hyperspectral maps of Ryugu samples were acquired over several hundreds of µm in size.
The IR absorption spectra of both A0108 and C0109 particles were almost identical, and typically consistent with CI
chondrites. However, some local heterogeneity exists, e.g., IR spectra from some areas were dominated by carbonate features,and opaque minerals are seen in high resolution hyperspectral maps. They display Mg-rich phyllosilicate bands at ~1000 cm-1
(Si-O stretching) and ~3700 cm-1 (OH group in phyllosilicates), organic bands (aliphatic C-H) at 3000-2800 cm-1. The positionand narrowness of the OH band fit those observed in spectra collected in-situ by the spacecraft [11]. Compared to thereflectance spectra obtained by JAXA curation [12], the OH band and aliphatic C-H bands features in the absorption spectra
were roughly consistent, but the abundance of aliphatic C-H peaks were lower than the reflectance spectra. Such differences
could be due to the difference between reflectance spectra and transmission spectra of sample particles. Also, interesting
behavior was observed during FTIR analysis, in that the aliphatic C-H peak increased during analysis for a few hours, likely
due to adsorption of environmental volatile organic compounds (VOCs). It is known that porous OH bearing silicates adsorb

VOCs [e.g., 13-15], particularly when fresh surfaces are exposed by sample crushing [16], however the Ryugu samples appear
unusually reactive and absorb VOC very rapidly, considering that the Ryugu sample analysis was conducted in a clean
environment without abundant contamination sources. This behavior indicates that Ryugu samples are fresh and highly porous.
Measurements conducted under vacuum and gentle heating reveal a rapid and dramatic disappearance of adsorbed water, alongwith an increase of the aliphatic band intensity. This has been previously observed for CI chondrites [6,17,18], and confirms
the high adsorption properties of Ryugu samples. Tight interactions between organics and -OH in phyllosilicates may accountfor this spectral evolution.
Overall, the FTIR organic signatures of the Ryugu samples do not point to a significant post-accretional heating as
observed in heated CM/CI chondrites [19]. Acid extraction of Ryugu samples very soon will provide a fresh IOM isolate, andthereby enable quantitative characterization of chemical group abundances.
References[1] Keller L. P. et al. 2004. Geochimica et Cosmochimica Acta 68: 2577. [2] Osawa T. et al. 2005. Meteoritics & Planetary
Science 40: 71-86. [3] Sandford S. A. et al. 2006. Science 314: 1720. [4] Beck P. et al. 2014. Icarus 229: 263. [5] Dartois E. et
al. 2018. Astronomy & Astrophysics 609: A65. [6] Battandier M. et al. 2018. Icarus 306: 74. [7] Kebukawa Y. et al. 2019.
Meteoritics & Planetary Science 54: 1632. [8] Cloutis E. A. et al. 2011. Icarus 212: 180. [9] Cloutis E. A. et al. 2011. Icarus
216: 309. [10] Cloutis E. A. et al. 2012. Icarus 217: 389. [11] Kitazato K. et al. 2019. Science 364: 272. [12] Yada T. et al.
2021. Nature Portfolio, under review. [13] Pires J. et al. 2001. Microporous and Mesoporous Materials 43: 277. [14] Li X. et al.
2020. Separation and Purification Technology 235: 116213. [15] Zhu L. et al. 2020. Journal of Hazardous materials 389:
122102. [16] Kebukawa Y. et al. 2009. Meteoritics & Planetary Science 44: 545. [17] Beck P. et al. 2010. Geochimica et
Cosmochimica Acta 74: 4881. [18] Takir D. et al. 2013. Meteoritics & Planetary Science 48: 1618. [19] Nakamura T. et al.
2005. Journal of Mineralogical and Petrological Sciences 100: 260.

Thermal history of Ryugu based on Raman characterization of Hayabusa2 samples
Lydie Bonal1, Eric Quirico1, Mutsumi Komatsu2, Gilles Montagnac3, Hikaru Yabuta4 and The Hayabusa2-initial-analysis IOM
team, Hisayoshi Yurimoto5, Tomoki Nakamura6, Takaaki Noguchi7, Ryuji Okazaki8, Hiroshi Naraoka8, Kanako Sakamoto9,
Shogo Tachibana9, 10, Sei-ichiro Watanabe11 and Yuichi Tsuda91Institut de Planétologie et d’Astrophysique de Grenoble, Université Grenoble Alpes, CNRS CNES, Grenoble, France
2
SOKENDAI, The Graduate Univ. for Advanced Studies
3
Laboratoire de géologie de Lyon, CNRS/INSU - ENS de Lyon, Lyon, France
4
Hiroshima Univ., 5Hokkaido Univ.,6Tohoku Univ., 7Kyoto Univ.,8Kyushu Univ., 9JAXA, 10Univ. of Tokyo, 11Nagoya Univ.

Introduction: The degree of structural order of the polyaromatic carbonaceous matter present in extraterrestrial samples is a
tracer of the thermal history they experienced (e.g., primitive chondrites: [1-4]; micrometeorites: [5-6]). To characterize
Ryugu’s thermal history (long vs. short thermal heating and extent of thermal heating), we thus perform Raman
characterization of several Ryugu particles returned by the Hayabusa2 mission. In order to be fully confident in the obtained
data and interpretation, Raman characterization was led independently by two groups of persons in Japan and in France on
distinct Ryugu particles. The results were subsequently compared.
Samples and methods: Raman point analyses were performed on several fragments of six particles from Chamber A
aggregates (A0108) and six particles from Chamber C aggregates (C0109). To be able to combine in situ IR and NanoSIMS
measurements on the same samples, fragments of particles were manually selected under a binocular and pressed onto
diamond windows. The Raman spectra were acquired with a 532 nm laser in both Japan and France. Because some Raman
bands related to carbonaceous matter are dispersive, data for Ryugu particles and comparison samples have been acquired andanalyzed consistently in both Japan and in France. In particular, a Renishaw InVia Reflex equipped with a 1800 l/mm grating
at Materials Characterization Central Laboratory was used in Waseda University (Japan). The laser was focused at the sample
surface through a 50× objective (spot size around 3-4 μm) and its power was set at 0.24 mW and 1 mW. Each acquisition
comprised five integrations of 10 s that were averaged to make the final spectrum. In France, Raman measurements were
performed at the Ecole Normale Supérieure de Lyon (Laboratoire de Géologie de Lyon—Terre, Planètes, Environnement)using a LabRam Raman spectrometer (Horiba Jobin-Yvon) equipped with a 600 g/mm grating. The laser was focused througha 100× objective to obtain a <2 μm spot size. The power on the sample was 0.3 mW. Each acquisition comprised six
integrations of 15 s that were averaged to make the final spectrum.
Results and discussion: More than 200 spectra were acquired on 12 different particles. The Raman data acquired in Japan andin France are fully consistent. Each acquired spectrum is characterized by a high fluorescence background and by the presenceof the Raman D- (~ 1350 cm-1) and G-bands (~ 1580 cm-1), related to the presence of polyaromatic carbonaceous matter. The
spectral parameters derived from the mathematical fitting of the individual spectra, that is, the band widths (FWHM-D,
FWHM-G), the band positions (ωD, ωG), and the band intensity ratio (ID/IG) are comparable between particles. No systematicdifferences have been observed to date between the spectral parameters of Chamber A and Chamber C particles. This point
will be further investigated on insoluble organic matter isolated by acid treatment of Ryugu samples.
The Ryugu particles contain polyaromatic carbonaceous matter that is poorly structured, as reflected by the high fluorescencebackground superimposed to wide D- and G-Raman bands, present at relatively low Raman shifts. The comparison of these
spectral parameters with similarly characterized chondrites shows that the structural order of the polyaromatic carbonaceous
matter present in Ryugu particles is comparable to that in primitive (type 1, type 2) carbonaceous chondrites. Ryugu thus
escaped significant degree of long duration radiogenic thermal metamorphism (as typically experienced by type 3 chondrites),
as well as short-duration heating as experienced by some type 2 chondrites (e.g., [4]).
References[1] Bonal et al. 2006. Geochimica Cosmochimica Acta 70 :1849. [2] Bonal et al. 2016. Geochimica Cosmochimica Acta 189:
312. [3] Busemann et al. 2007. Meteoritics & Planetary Science 42: 1387. [4] Quirico et al. 2018. Geochimica Cosmochimica
Acta 241 : 17 [5] Dobrica et al. 2011. Meteoritics & Planetary Science 46 : 1363. [6] Battandier et al. 2018. Icarus 306 : 74.

Elemental and isotopic compositions of organic grains from asteroid Ryugu
Laurent Remusat1, Maximilien Verdier-Paoletti1, Smail Mostefaoui1, Lydie Bonal2, Hikaru Yabuta3 and The Hayabusa2initial-analysis IOM team, Hisayoshi Yurimoto4, Tomoki Nakamura5, Takaaki Noguchi6, Ryuji Okazaki7, Hiroshi Naraoka7,
Kanako Sakamoto8, Shogo Tachibana8, 9, Sei-ichiro Watanabe10 and Yuichi Tsuda8
1Museum National d’Histoire Naturelle, CNRS, Sorbonne Université, Paris, France. 2Institut de Planétologie etd’Astrophysique de Grenoble, Université Grenoble Alpes, CNRS CNES, Grenoble, France 3Hiroshima Univ., 4Hokkaido
Univ.,5Tohoku Univ., 6Kyoto Univ.,7Kyushu Univ., 8JAXA, 9Univ. of Tokyo, 10Nagoya Univ.

Introduction: Isotope composition of organic material found in extraterrestrial samples is a powerful proxy for tracking its
origin and evolution during the solar system events [1,2]. In situ investigation of isotope and elemental compositions unravel
the heterogeneity and diversity of organic particles embedded within the fine-grained minerals of chondrites and IDPs [3,4].
Understanding the origin of organic matter on carbonaceous asteroids and its subsequent evolution due to secondary processes
as well as space weathering is one of the prime goals of the Hayabusa2 sample-return mission [5]. To document Ryugu’s
inventory of organic material, we have employed NanoSIMS imaging of intact grains, without any chemical treatments, fromboth Chamber A and Chamber C. We present here the first set of data acquired on the NanoSIMS installed at the National
Muséum of Natural History in Paris, and compare the composition of organic particles from the two sampling sites to evaluate
the influence of space weathering and aqueous alteration.
Samples and methods: Several fragments of 3 particles from Chamber A aggregates (A0108) and 3 particles from Chamber C
aggregates (C0109) were manually selected under a binocular and pressed on diamond windows. After their analysis by
Raman and transmission FTIR, samples were gold coated (about 25 nm thick) before NanoSIMS imaging. In the first step,secondary ions of 16O, 12C2, 12C14N, 12C15N and 32S were imaged in multicollection mode, to investigate N-isotope distributions
as well as N/C, O/C and S/C elemental ratios. A 2-3 pA primary Cs+ beam with a spatial resolution around 200 nm wasrastered over 20 by 20 Pm2, divided into 256 by 256 pixels, in association with an electron flooding gun for charge
compensation. Dwell time was set at 2 ms/pixel and about 60 frames were stacked.
Results and discussion: About 11,600 and 9,600 Pm2 surface area were imaged, of Chamber A and Chamber C samples,
respectively. Individual organic particles were identified using the L’image software developed by Larry Nittler (Carnegie
Institution of Washington). The 15N/14N ratios of individual particles are comparable to the values for isotope anomalies in CI
and CM insoluble organic matter [3,6,7] whilst samples from Chamber C tend to exhibit a slightly larger 15N enrichment. In
addition, bulk organic G15N is in the range of IOM in CI chondrites. These values are consistent with independent NanoSIMS
measurements of other Ryugu aggregates [8]. The corresponding elemental ratios point to a larger content in N in the organic
particles from Chamber A, while the particles from Chamber C are more O-rich. Overall, S content is similar in organic
particles from both chambers. It must be noted that O/C and S/C may be biased by the occurrence of fine scale association ofoxides/silicates and sulfides with the organic particles, as observed by TEM [9]. The elemental composition of particulateorganic matter will be further investigated on insoluble organic matter isolated by acid treatment of Ryugu samples. Our datasuggest differences between aggregates from the two sampling sites in terms of elemental and isotope compositions ofindividual organic particles.
References[1] Remusat et al. 2010. ApJ 713:1048. [2] Alexander C. M. O’D. et al. 2017. Chemie der Erde - Geochemistry 77:227. [3]Busemann et al. 2006. Science 312 :727. [4] Remusat et al. 2009 ApJ 698 :2087. [5] Tachibana et al. 2014. Geochem. J.
48:571. [6] Alexander et al. 2010. GCA 74:4417. [7] Remusat et al. 2019. GCA 263:235. [8] Nittler et al. 2021. Thisconference. [9] Stroud et al. 2021. This conference.

Exposure Conditions of Samples Collected on Ryugu’s Two Touchdown Sites Determined by
Cosmogenic Nuclides
Kunihiko Nishiizumi1, Marc W. Caffee2, Keisuke Nagao3, Ryuji Okazaki4, Hisayoshi Yurimoto5, Tomoki Nakamura6, Takaaki
Noguchi7, Hiroshi Naraoka4, Hikaru Yabuta8, Kanako Sakamoto9, Shogo Tachibana9, 10, Sei-ichiro Watanabe9, 11, Yuichi
Tsuda9, and Hayabusa2 Initial Analysis Volatile Team
1
Space Sci. Lab., Univ. of California, Berkeley, CA 94720-7450, USA., 2Dept. of Phys. & Astro., Purdue Univ., West Lafayette,
IN 47907-2036, USA., 3KOPRI, Incheon 21990, Korea, 4Kyushu Univ., Fukuoka 819-0395, Japan, 5Hokkaido Univ.,
6
TohokuUniv., 7Kyoto Univ., 8Hiroshima Univ., 9ISAS/JAXA, 10Univ. of Tokyo, 11Nagoya Univ.
Hayabusa2 arrived at the C-type asteroid 162173 Ryugu in Jun. 2018, and successfully collected surface samples from two
sampling sites, returning ~5.4 g of samples to Earth on Dec. 6, 2020. Surface samples stored in Chamber A were collected by
the 1st touchdown (TD) on Ryugu’s surface on Feb. 21, 2019. A crater (diameter of ~14 m) on Ryugu’s surface was madeusing a collision device - denoted “Small Carry-on Impactor (SCI)” - on Apr. 5, 2019 [1]. Samples in Chamber C were collected
proximal to this artificial crater and are possibly ejecta from the north side of the crater by the 2nd TD on Jul. 11, 2019 [2].
Our studies are based on the measurement of those nuclides produced in asteroidal surface materials by cosmic rays - bothsolar and galactic cosmic rays. Cosmic-ray-produced (cosmogenic) nuclides are used to determine the duration and nature of
the exposure of materials to energetic particles. Our goals are to understand both the fundamental processes on the asteroidal
surface and the evolutionary history of its surface materials. They are also key to understanding the history of Ryugu’s surface
and asteroid-meteoroid evolutionary dynamics. For Hayabusa2 samples, there are several specific questions we aim to address:(1) are the Chamber C samples, collected during the 2nd touchdown ejecta deposits from the artificial crater, (2) if so, what is theoriginal depth of each recovered sample in the Ryugu regolith, and (3) what is the surface exposure time, mixing rate, anderosion/escape rate of Ryugu’s surface? To answer these questions, we were allocated and received 2 particles from Chamber
A (A0105-19 and -20) and 3 particles from Chamber C (C0106-09, -10, and -11) for measurements of cosmogenic radionuclides
and noble gases. Each sample is several hundred µm in size.
We transferred the individual grains to acid cleaned sapphire containers, with ~2 mm diameter hole, using a vacuum tweezer
at the JAXA curation facility. The five samples were hand carried to the Space Sciences Laboratory (SSL), University ofCalifornia, Berkeley. Each sample was gently crushed by a mortar and pestle made from sapphire and then divided into two
fractions, one fraction for cosmogenic radionuclides and one for noble gases. The samples were individually transferred to asmall Al weighing boat and the masses were determined using an ultra-micro balance. For cosmogenic radionuclide analysis,
the sample was transferred to a Teflon bomb from the Al boat and dissolved with a few drops of HF-HNO3 mixture in thepresence of clean Be, Al, Cl, and Mn carriers. After Cl was separated as AgCl, a small analysis aliquot was taken for chemical
analysis by ICP-OES (Table 1). Beryllium and Al were separated by ion chromatography, using 1 mL anion and cation ion
exchange columns, and purified for accelerator mass spectrometry (AMS) measurements. To serve as a baseline comparison,
three grains of the Nogoya CM2 chondrite were analyzed using the same protocols.
Beryllium-10 (t1/2 = 1.36 x 106 yr) AMS analysis was performed at PRIME lab, Purdue University [3] and result was shownin Table 1. Analyses of 26Al (7.05 x 105 yr) and 36Cl (3.01 x 105 yr) as well as noble gases will be done in the near future.
Table 1. Chemical compositions and cosmogenic nuclide 10Be concentration in Hayabusa2 samples and Nogoya CM2 chondrite.
SampleHayabusa2 A0105-19
Hayabusa2 A0105-20
Hayabusa2 C0106-09
Hayabusa2 C0106-10
Hayabusa2 C0106-11
Nogoya CM2
Nogoya CM2
Nogoya CM2

Mass
(mg)
0.24290.20610.12280.15430.18980.45940.34370.2049

Mg
(%)
8.18
8.41
6.05
7.97
8.45
9.96
9.61
11.27

Ti
(ppm)
470
720
690
490
450
480
480
410

Mn
(ppm)
(2010)(2090)
1800
1680
1710

Fe
(%)
17.6
18.0
19.5
21.0
21.5
20.0
19.9
19.8

Co
(ppm)
590
460
580
440
430
580
540
380

Ni
(%)
1.00
1.03
1.36
1.43
1.29
1.18
1.17
1.20

10

Be
(dpm/kg)
12.76 ± 0.37
12.75 ± 0.29
7.10 ± 0.30
7.48 ± 0.26
7.21 ± 0.43
2.09 ± 0.13
2.12 ± 0.09
2.00 ± 0.13

Mn concentrations in parentheses are large uncertainty.

Although the chemical compositions of all 5 Hayabusa2 particles are very similar, the concentrations of Fe and Ni of the 3
Chamber C samples are ~10 % higher than that of Chamber A samples. Our measurements of the 5 Hayabusa2 samples indicatethat the chemical composition of Ryugu is closer to those of CI or CM carbonaceous chondrites, rather than CV or CO.

To validate our procedures we measured the 10Be concentrations in 3 individual grains from Nogoya. The concentrations
from the Nogoya grains are nearly identical and in good agreement with our previous measurement of 2.22 ± 0.10 dpm/kg. The
measurements reported here used ~3 orders of magnitude less sample mass than the measurements made years ago, haveessentially the same uncertainties. For Ryugu, we were able to obtain high quality 10Be measurements using ~100 µg sample.
The surface of Ryugu is bombarded by cosmic ray in a 2π exposure geometry, similar to surface of the Moon. On the Moon,
the production profile of cosmogenic 10Be from the surface to a depth of over 400 g/cm2 is well established by measurements of
10
Be concentrations in the Apollo 15 drill core and 15008/7 core, shown in Fig. 1 [4, 5]. The 10Be concentrations in A0105-19
and -20 are equivalent to the saturation value measured at the surface of the Moon. The simplest scenario is that both A010519 and -20 were collected from a depth of 0-30 g/cm2 on Ryugu. Both samples have been continuously exposed to cosmic ray
at a similar depth for more than several Myr. A more precise depth can be obtained by measurement of 26Al, which has adifferent production profile than 10Be, and is also produced by solar cosmic ray at shallow depth (≤ several g/cm2). Since the10
Be activity is saturated, the total exposure age must be obtained by measurements of longer half-life (3.7 x 106 yr) 53Mn andcosmogenic noble gases. Beryllium-10 concentrations in three Chamber C samples are lower than that of the Chamber A
samples but nearly the same as each other. The sampling location of the 2nd TD is close to the ”ejecta ray 3” described by [1].
Assuming that the Chamber C samples were shielded during their exposure to cosmic rays and then were incorporated into theejecta deposits from the artificial crater by SCI impact, we can calculate the depth at which they were exposed. All three
Chamber C samples were ejected from a depth of 150 – 180 g/cm2 from Ryugu (see Fig. 1). This depth corresponds to 1.3 –1.5 m, assuming the regolith density is the same as Ryugu’s bulk density of 1.2 g/cm3 [6]. Since the depth of the crater floor
from the initial surfaces was determined 1.7 m by a digital elevation map (DEM) [1], three Chamber C samples were ejectedfrom near bottom of the crater. Alternatively, if we assume these were not ejecta, but were resident on the surface, the lower
10
Be activities would indicate that these grains have shorter exposure ages, ~ 1 Myr. Based on their location near the artificial
crater ejecta ray, we consider this scenario unlikely. Aluminum-26 and 36Cl measurements of these samples will further
constrain ejection depth and condition.
For our work, we obtained 5 similar sized, ~0.5 – 1 mm, grains. We don’t know whether the sizes we observe now are
representative of the grain’s original sizes on Ryugu’s surface; it is possible that they were broken during the collection process
or during sample handling. We are certain though that independent of their original size on Ryugu, the three Chamber C grains
were exposed to cosmic rays at the same depth. These grains had ample 10Be for measurement, 10Be measurements are possible
in smaller grain sizes. A logical next step would be the measurement of 10Be in grains of different sizes to investigate whether
any possible association of grain size and ejection depth.
Based on saturated 10Be in surface samples and from ejecta samples we conclude that the surface of Ryugu has been exposed
to cosmic rays for more than several Myr and that the upper 1 - 2 m of regolith have been relatively undisturbed for more thanseveral Myr. Our observation shows that the surface of Ryugu is more stable than the surface of Itokawa and the estimation bygeomorphological indicators [7]. Additional cosmogenic nuclide measurements, especially stable noble gases, will allow adetailed understanding of the surface evolution of Ryugu.
15

Figure 1.
10
Be

10

10

Be (dpm/kg)

10
9
8

Be

The depth profile of 10Be production on the Moon.

Black diamonds indicate 10Be concentration vs. depth on the Moon
measured in undisturbed Apollo 15 drill core and 15008/7 core [4,A0105

5]. Observed 10Be concentrations in Hayabusa2 samples are plot
at estimate depths on Ryugu and marked red circle (A0105) andC0106

square (C0106).

7

References: [1] Arakawa M. et al. 2020. Science 368, 67-71. [2]6Tsuda Y. et al. 2020. Acta Astronautica 171, 42-54. [3] Sharma P.

5

et al. 2000. NIM B172, 112-123. [4] Nishiizumi K. et al. 1984. EPSL
70, 157-163. [5] Nishiizumi K. and Caffee M. W. 2019. MAPS 54,

46087pdf. [6] Watanabe S. et al. 2019. Science 364, 268-272. [7]30Sugita S. et al. 2019. Science 364, eaaw0422.

50

100

150
200
2
Depth (g/cm )

250

300

Acknowledgments: We thank Hayabusa2 project and initial analysis team, especially Hayabusa2 curation members. Z. Nett and K. C. Welten
helped a part of laboratory works. Nogoya was obtained from Field Muse. of Nat. His. This work was supported by NASA’s LARS program.

Small grains from Ryugu: handling and analysis pipeline for Infrared Synchrotron
Microspectroscopy
Stefano Rubino1, Zélia Dionnet1, Alice Aléon-Toppani1, Rosario Brunetto1, Tomoki Nakamura2, Donia Baklouti1, Zahia
Djouadi1, Cateline Lantz1, Obadias Mivumbi1, Ferenc Borondics3, Stephane Lefrançois3, Christophe Sandt3, Francesco
Capitani3, Eva Héripré4, David Troadec5, Megumi Matsumoto2, Kana Amano2, Tomoyo Morita2, Hisayoshi Yurimoto6,
Takaaki Noguchi7, Ryuji Okazaki7, Hikaru Yabuta8, Hiroshi Naraoka7, Kanako Sakamoto9, Shogo Tachibana9-10, Sei-ichiro
Watanabe11, Yuichi Tsuda9, and the Hayabusa2-initial-analysis Stone team1

IAS, Université Paris-Saclay, CNRS, France, 2Tohoku University, Japan, 3SMIS-SOLEIL, FranceCentraleSupélec, Université Paris-Saclay, CNRS, France, 5IEMN, Université de Lille, France, 6Hokkaido University, Japan,
7
Kyushu University, Japan, 8Hiroshima University, Japan, 9ISAS/JAXA, Japan, 10The University of Tokyo, Japan, 11Nagoya
University, Japan

4

Introduction: In December 2020, the sample return mission
Hayabusa2 (JAXA) brought 5.4g of matter from the surface of Ctype primitive asteroid (162173) Ryugu [1]. This extremely
precious material is now the object of multiple studies with stateof-the-art techniques in laboratories all around the world (Initial
Analysis phase). These studies will grant new insight on the origin
and evolution of primitive hydrated planetesimals, and ultimately
on the early stages of our solar system. Within the Hayabusa2initial-analysis “Stone” team [1] led by T. Nakamura, we received
several microscopic particles in July 2021, with the goal of
performing IR hyper-spectral imaging and IR micro-tomography
studies.
Samples transfer and handling: Ryugu samples are kept in acontrolled N₂ environment at Sagamihara (JAXA) in order toFigure 1. Sample-holder description
avoid exposure to the terrestrial atmosphere. We took several steps
in order to minimize the samples’ exposure to air, before, during
and after measurements. Prior to receiving the samples, we designed a custom sample-holder (Figure 1) for transferring particles
from Japan to France and for their preliminary analysis. Particles from Ruygu were deposited on a gold mirror inside the sampleholder at Tohoku University (Japan). A KBr window installed in the cover of the sample-holder allowed us to acquiremeasurements of the particles while the sample-holder was still sealed. This custom-made sample-holder was kept as clean andsterile as possible (to avoid terrestrial contamination) and it had to fulfill two major requirements: fit on the microscope stages
for our IR imaging and microspectroscopy studies and keep the samples in a dry N₂ environment (to avoid alteration from theatmosphere). The sample-holder was assembled inside a glovebox under N₂ atmosphere (ΔP ~ 6 mBar, H₂O = 1.0 ppm, O₂ = 1.2
ppm). Multiple interfaces were used in order to prevent the mixing of the clean N₂ atmosphere and the ambient air (gold gasket,
cleanroom static shielding bags), but also to avoid issues from shocks and vibrations (membrane boxes, foam-padded case).
Once in Sendai, the empty sample holders were opened in a glovebox, and were loaded with 32 microscopic particles from
Ryugu (distributed among four sample-holders: 14 particles from the first touchdown site in SH2 and SH3, and 18 particles fromthe second touchdown site in SH1 and SH4).
To monitor the atmosphere’s changes in our sample-holders, these were accompanied by a “control”-holder, with grains ofolivine and Fe dust (to monitor hydration and oxidation). A second “control”-holder, loaded with drierite (calcium sulfate) andsome Fe dust, was kept in France, to monitor hydration and oxidation when not under dry N₂ conditions.
Samples reception and characterization: Upon arrival at synchrotron SOLEIL (France) in early July, the sample holders were
inspected with a binocular through the KBr windows. We were able to identify at least 24 out of 32 of the original Ryugu
particles, either based on their morphological correspondence with the grains prepared at Tohoku, and/or thanks to their clear IR“Ryugu-like” spectral signatures (mainly the 2.7 µm feature [2]). The particle size range was from 20 to 80 µm, with a particularly
large particle in SH4 larger than 100 µm.
The analytical pipeline started with a full spectral characterization using the IR synchrotron beam while keeping the sampleholder closed, in order to minimize exposure to air. During the first three weeks of July, we analyzed all the identified Ryugu
grains in their sample holders using three different FTIR microscopes: (1) a mid-IR large wavelength range MCT/B-equippedand synchrotron-radiation-fed microscope, (2) a far-IR bolometer-equipped microscope, (3) an FPA-equipped imaging
microscope. Multiple detectors were used to access different wavelength ranges, covering from near-IR to far-IR (1 µm to 35µm). This large spectral coverage allowed us to detect carbonates, organics, and phyllosilicates with different band positions [3].
Most of the IR spectra showed interesting features. Hyperspectral maps in the mid-IR of the individual particles were alsoacquired, in order to assess the compositional heterogeneity at the 5-10 µm scale. A few Raman spectra and maps were alsoacquired on isolated fragments, to assess the presence and structure of endemic organics in Ryugu’s particles and to getcomplementary information on the mineralogy.

Thanks to a Raman measurement on a µm-spot on the gold substrate, we managed to detect remotely molecular oxygen inside
SH2, which indicates the holders at some point lost their air-shut condition, probably in flight from Japan to France. We estimatethat the grains were exposed to air for about 72-96 hours, before we received them and we put them again into a dry N2
environment. However, we did not observe any modification of the KBr (a control KBr window we exposed to air for 24h
showed clear modifications), and the anhydrous control samples we sent along the Ryugu sample holders showed no evidenceof water adsorption nor hydration. So we inferred that Ryugu grains remained in a relatively dry environment, although inpresence of O2, probably thanks to the presence of desiccants that prevented an increase in humidity.
In mid- and late-July, we opened sample holders SH2 and SH3, and we mounted 6 Ryugu grains on W or Al needles using two
different FIB-SEM microscopes in Saclay and in Lille [4]. These grains were then measured in both transmission and reflectancemode, by Infrared Computed Tomography [5] (IR-CT) and Infrared Surface Imaging [6] (IR-SI) respectively. IR-CT allows us
to assess the compositional heterogeneity of small particles in a 3D space, while IR-SI allows us to assess the surface composition
for larger particles, treating the grain as a planetary surface by projecting the 2D IR hyper-spectral maps on a 3D shape model.
Data processing and analysis of this large set of data is still ongoing. Our primary method of analysis, IR spectroscopy, is totally
non-destructive, which implies that after our measurements a few particles can be sent to other analytical teams in the scope of
combining different studies on the same sample. Some of these particles are now being analyzed by X-ray computed tomography
at SPring-8 (Japan) [7].
Overall, the outcome of the last months has shown that the agreed handling, transfer and analysis pipelines are valid and may be
applied for future sample-return missions.
Acknowledgements: We thank Moe Matsuoka for her precious help in preparing and sending Ryugu’s particles from SendaiJapan all the way to Orsay-France. This work is part of the multi-analytical sequence of the Hayabusa2 “Stone” MIN-PET group,
led by Tomoki Nakamura. Zélia Dionnet was supported by a CNES postdoctoral allocation and this work was supported by theCentre National d’Etudes Spatiales (CNES-France, Hayabusa2 mission). The micro-spectroscopy measurements were supported
by grants from Region Ile-de-France (DIM-ACAV) and SOLEIL.
References[1] T. Nakamura et al., abstract in this volume ; [2] K. Kitazato et al., Science, 2019, 364, 272–275. ; [3] Z. Dionnet et al, abstract
in this volume ; [4] A. Aléon-Toppani et al., Meteorit. Planet. Sci., 2021, 56, 1151–1172. ; [5] Z. Dionnet et al. 2020. Meteoritics& Planetary Science 55 ; [6] Z. Dionnet et al., in preparation, 2021. ; [7] A. Tsuchiyama et al., abstract in this volume.

Preliminary results from FTIR hyper-spectral imaging campaign on Ryugu small grains andfragments.
Zélia Dionnet1, Stefano Rubino1, Alice Aléon-Toppani1, Rosario Brunetto1, Tomoki Nakamura2, Donia Baklouti1, Zahia
Djouadi1, Cateline Lantz1, Ferenc Borondics3, Christophe Sandt3, Eva Héripré4, David Troadec5, Megumi Matsumoto2, Kana
Amano2, Tomoyo Morita2, Hisayoshi Yurimoto6, Takaaki Noguchi7, Ryuji Okazaki7, Hikaru Yabuta8, Hiroshi Naraoka7,
Kanako Sakamoto9, Shogo Tachibana9-10, Seiichiro Watanabe11, Yuichi Tsuda9 and the Hayabusa2-initial-analysis Stone team.
1

IAS, Université Paris-Saclay, CNRS, France, 2Tohoku University, Japan, 3SMIS-SOLEIL, FranceCentraleSupélec, Université Paris-Saclay, CNRS, France, 5IEMN, Université de Lille, France, 6Hokkaido University, Japan,
7
Kyushu University, Japan, 8Hiroshima University, Japan, 9ISAS/JAXA, Japan, 10The University of Tokyo, Japan, 11Nagoya
University, Japan

4

Introduction: Hayabusa2 is the first sample return mission to study and return samples from a primitive carbonaceous
asteroid. It thus allows the study of the same small body at very different scales, from the km down to the atomic scale. Infrared(IR) spectroscopy plays a crucial role in this respect, helping to build a bridge between the remote sensing observations of theasteroid’s surface, performed by NIRS3 [1,2] and the chemical and physical processes operating at a smaller scale andcharacterized in the laboratory on the returned samples. In December 2020, the Hayabusa2 reentry capsule delivered 5.4 g ofmaterial coming from asteroid Ryugu. This extremely precious material was then recovered by JAXA and pre-characterized
inside the ISAS curation facility [3,4]. A fraction of this material was then given to six Initial Analysis sub teams, including the“Stone” team led by T. Nakamura which studies mineralogy and petrology at a large scale [5].
Material and Methods: We will present the result of FTIR hyperspectral imaging on six micrometric Ryugu fragments(ranging from 30 to 80 µm in size). These fragments originate from 2 bigger millimetric grains (A0064 and C0046). We analyzed
these small grains in multiple configurations (see detailed analytical plan and transportation issues in [6]). After the firstcharacterization in reflectance mode on their gold substrate, we mounted these small grains at the top of metallic needles toanalyze them at different rotating angles both in transmission and reflection modes. The obtained data in transmission mode, IRCT [7] (Infrared Computed Tomography), were then analyzed to reconstruct 3D distributions of the molecular components inside
the grains, while reflectance data were projected on a 3D shape model of the grains. In this case, the fragments were treated as aplanetary surface, which will also help to reinforce the link between remote sensing and laboratories measurements. Taking
advantage of each configuration, the preliminary results of the combination of the different measurements will be shown anddiscussed.
Results and Discussion: We will present the average spectra in the 2.5 – 30 µm range. Several grains have IR signaturesat 2.7 µm, 3.0-3.1 µm, 3.4 µm, and 3.9 µm, in a good agreement with the bands identified by NIRS3 or by MicrOmega and FTIR
in the JAXA curation facility [3, 4], plus several mid-IR signatures of great interest, such as bands attributed to Si-O stretchingin phyllosilicates, and C=O stretching in organics and carbonates. A comparison of the IR spectra of the different grains withthose of a large variety of carbonaceous chondrites acquired with the same set-up will be presented. Finally, we will discuss theheterogeneity within individual grains, with particular emphasis on the following issues: (i) detection and heterogeneity of the
2.7 µm band (ii) spatial correlation between phases (phyllosilicates, carbonates, opaque phases, organics) and (iii) identificationand quantification of the carbonates. These spectral observations and parameters will help to better constrain the 3D μm-scaleassembly of minerals and organics in Ryugu, and will provide information on the origin and evolution of Ryugu.
Perspectives: Our multi-analytical sequence started with non-destructive IR hyperspectral imaging and continues now
with more destructive techniques. One grain has been sliced into 3-µm thin sections and will be analyzed in 2D with higher
resolution IR hyperspectral imaging and complementary analyses [8]. The rest of the samples have been sent back to Japan, tobe analyzed at the BL47XU of SPring-8 synchrotron by XCT [9] in order to obtain complementary information concerning the3D physical, chemical and morphological properties.
Acknowledgments: We thank Moe Matsuoka for her precious help in preparing and sending Ryugu’s particles from
Sendai-Japan all the way to Orsay-France. This work is part of the multi-analytical sequence of the Hayabusa2 “Stone” MINPET group, led by Tomoki Nakamura. Zélia Dionnet was supported by a CNES postdoctoral allocation and this work was
supported by the Centre National d’Etudes Spatiales (CNES-France, Hayabusa2 mission). The micro-spectroscopy
measurements were supported by grants from Region Ile-de-France (DIM-ACAV) and SOLEIL.
References: [1] Kitazato et al. 2019 Science 364-6437: 272. [2] Watanabe, S.-I., Tsuda, Y., Yoshikawa, M., et al. 2017,
Space Science Review, 208: 3. [3] Bibring et al. 2021. Metsoc Abstract #6276. [4] Yada et al. 2021. Metsoc Abstract #6186. [5]Nakamura et al. in this volume. [6] Rubino et al. in this volume. [7] Dionnet et al. 2020. Meteoritics & Planetary Science 55:
1645-1664. [8] Aléon-Toppani et al. 2021. Meteoritics & Planetary Science. [9] Tsuchiyama A. et al. 2011. Science 333-6046:
1125.

Iron valence state and mineralogy in particles from asteroid Ryugu
Jean-Christophe Viennet1, Mathieu Roskosz1, Pierre Beck2, Esen Ercan Alp3, Barbara Lavina3,4, Michael Hu3, Jiyong Zhao3,
Tomoki Nakamura5, Kana Amano5, Mizuha Kikuiri5, Tomoyo Morita5 Hisayoshi Yurimoto6, Takaaki Noguchi7 Ryuji
Okazaki8 Hikaru Yabuta9, Hiroshi Naraoka8, Kanako Sakamoto10, Shogo Tachibana10 ,11, Seiichiro Watanabe12, Yuichi
Tsuda10, and the Hayabusa2-initial-analysis Stone team.
1

Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Museum National d’Histoire Naturelle, CNRS,
Sorbonne Université, Paris, France. 2Institut de Planétologie et d’Astrophysique de Grenoble, Université Grenoble Alpes,
CNRS CNES, Grenoble, France. 3Center for Advanced Radiation Sources, The University of Chicago, Chicago, IL 60637,
USA.4Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA. 5Tohoku Univ. 6Hokkaido
Univ.7Kyoto Univ. 8Kyushu Univ. 9Hiroshima Univ. 10JAXA. 11Univ. of Tokyo, 12Nagoya Univ.
Introduction: Iron is a major element in rocky material from the solar system that can occur under multiple valence state. As
such it can be used to trace geological processes that occurred on asteroid Ryugu, including thermal metamorphism andaqueous alteration. Observations of the mineralogy of carbonaceous chondrites have revealed the presence of minerals
assemblages that are barely in thermodynamic equilibrium. Even at the micron-scale, iron is often present under multiple
valence state (most frequently 0, +2, or +3) in a wide range of minerals (primary or secondary in nature), including silicates,
oxy-hydroxide, sulfides, sulfates, clay minerals and carbonates. Such heterogeneous assemblages are the results of postaccretion processes that often triggered a partial textural and chemical equilibration, associated to a modification of primaryFe-bearing minerals and their valence state. It is therefore tricky to disentangle the different processes recorded by the ironmineralogy of chondritic materials. Furthermore, since most Fe-bearing phases are redox-sensitive, exposure to terrestrial
atmosphere may also induce iron oxidation and additional, late modifications of the iron mineralogy. In this context,
Hayabusa2 sampled Ryugu, an asteroid that did not suffer extensive thermal metamorphism, and returned rocks to Earth withminimal air exposure. It offers a unique opportunity to study the redox state of carbonaceous asteroids and evaluate the overall
redox state of the most oxidized primitive rocks of the solar system.
Samples and methods: Here, we determine the mineralogy and the redox state of Fe-bearing minerals from ten Ryugu
samples (five from the chamber A used for the first sampling and five from the chamber C for the second sampling) prior toand after exposure to air. We use Synchrotron Mössbauer Spectroscopy (SMS) technique that enables to probe the bonding
environment of iron at the microscopic scale. These measurements are combined with co-aligned X-ray diffraction, permitting
to assess locally the mineralogy and valence state of iron in Ryugu particles. We also apply conventional Mössbauer
spectroscopy on a couple of large (mm-size) Hayabusa returned samples from the chambers A and C.
Results and discussion: We will present the bulk proportions of iron-bearing minerals and the Fe redox state (Fe3+/Fetot) at the‘Stone’ scale. We will then provide the first estimate of the redox state of Ryugu as compared to the large array of bulk redox
data collected over several decades on meteorites. We will also describe the redox states of iron-bearing clay minerals before
any air contamination. The first clues on the ageing of these minerals after exposure to air will be discussed based on datacollected on the same sample before and after exposure to air. We will compare in greater details Ryugu samples to a series ofwell-known chondritic meteorites including Orgueil and Murchison. We will show, more specifically, that most of the iron isaccommodated in magnetite and sulfides (pyrrhotite and pentlandite). Clay minerals also contain a fraction of the total iron.
Overall, the investigated Ryugu samples appears to be (or are) more reduced than the Orgueil, both considering the bulk
composition and the clay minerals fraction. The redox state recorded in a pristine sample and in the same sample exposed to air
for more than two months do not show clear evidence of oxidation suggesting that, as far as iron is concerned, samples can beprepared and analyzed at ambient conditions at least for several weeks if stored in vacuum or in inert gas after preparation.

Three-dimensional analysis of Ryugu sample particles using X-ray nanotomography.
Akira Tsuchiyama1,2, Megumi Matsumoto3, Junya Matsuno1, Tomoki Nakamura3, Takaaki Noguchi4,5, Kentaro Uesugi6,
Akihisa Takeuchi6, Masanori Yasutake6, Miyake Akira4, Shota Okumura4, Yuri Fujioka3, Mingqi Sun2, Aki Takigawa7,
Toru Matsumoto4, Satomi Enju8, Itaru Mitsukawa4, Yuma Enokido3, Tomoyo Morita3, Naoto Nakano4 and Stefano Rubino9,
Tsukasa Nakano10 Hisayoshi Yurimoto11, Ryuji Okazaki12, Hikaru Yabuta13, Hiroshi Naraoka12, Kanako Sakamoto14,
Shogo Tachibana7,14, Seiichiro Watanabe15 and Yuichi Tsuda14, and the Hayabusa2-initial-analysis Stone and Sand teams
1Research Organization of Science and Technology, Ritsumeikan University, 2CAS, Guangzhou Institute of Geochemistry,
3Guraduate School of Science, Tohoku University, 4Guraduate School of Science, Kyoto University, 5Faculty of Arts andScience, Kyushu University, 6SPring8/JASRI, 7Guraduate School of Science, University of Tokyo, 8Guraduate School of Scienceand Engineering, Ehime University, 9Université Paris-Saclay, CNRS, Institut d’Astrophysique Spatiale, 10GSA/AIST,
11Guraduate School of Science, Hokkaido University, 12Guraduate School of Science, Kyushu University, 13Guraduate Schoolof Advanced Science and Engineering, Hiroshima University, 14ISAS/JAXAWe have performed initial analysis of samples returned from asteroid 162173 Ryugu by the Hayabusa2 spacecraft usingsynchrotron radiation-based X-ray nanotomography to elucidate the 3D structures and features of the samples with sub-micron
spatial resolution as parts of the Hayabusa2 initial analysis Stone and Sand sub-teams.
We analyzed 29 and 20 particles from the first and second touchdown sites (chambers A and C), respectively. Particles of
10 ~ 150 µm in apparent size were picked up and attached to the tips of Ti needles with Pt deposition using FIB or amorphous
carbon fibers with glycol phthalate. They were imaged by two different methods (dual-energy tomography (DET) [1] andscanning-imaging X-ray microscopy (SIXM) [2]) at BL47XU of SPring-8 [3]. In DET, X-ray absorption contrast images wereobtained as the spatial distribution of linear attenuation coefficient (LAC) at two different X-ray energies of 7 and 7.35 keV,which are below and above the K-absorption energy of Fe (7.11 keV), respectively. The LAC images at 7 keV correspondclosely to compositional (Z) contrasts, except for Fe, and those at 7.35 keV strongly depended on Fe content. In SIXM, we
obtained X-ray differential phase contrast images as the spatial distribution of refractive index decrement (RID), which is thedifference between the X-ray refractive index (RI) and unity (RI = 1 - RID), at X-ray energy of 8 keV. The RID image isclosely proportional to the density of the object. The voxel sizes of LAC 7 keV, LAC 7.35 keV and RID images are 47.4
47.447.4 nm3, 51.151.151.1 nm3 and 111.1111.1109.2 nm3, respectively.
The image analysis was made by combining ImageJ and codes made with C and Python. The registration among the three
types of images was made with the reference of LAC 7 keV images. Then, RGB-CT images were made by assigning blue, red,and green to LAC 7 keV, LAC 7.35 keV, and RID images, respectively. Different phases including organic materials show
different colors in the RGB-CT images. Minerals are quantitatively discriminated by comparing the LAC and RID values ofthe objects in CT images and those of minerals with known chemical compositions and densities. The solid portions of thesample particles images were extracted in LAC 7.35 keV using Chan-Base segmentation. The volume, V, surface area, S, 3axial lengths, A≥B≥C, fractal dimension, FD, and closed porosity, p0, were then obtained. Porosity by considering pores andcracks that are open to the outside, named as open porosity, p∞, were also estimated by a wrapping method [4]. The density, r,
was estimated from the averaged RID value of the particle as the lower limit. Density considering open pores, r∞, wascalculated as r(1- p∞). Sphere-equivalent diameter, D, was calculated from V and sphericity, Y, from V and A.
No distinct difference between the samples from chambers A and C was recognized. The sample particles are mainlycomposed of Mg-rich phyllosilicates (serpentine and/or saponite; Mg#~0.8-0.9) in the matrix (Fig. 1A). The phyllosilicates are
not homogeneous in some particles (Fig. 1B) probably due to the difference of Mg# and/or nanoporosity below the spatial
resolution. FeS (mostly pyrrhotite and minor pentlandite) grains are commonly present as hexagonal plates shown as arectangle shape in a slice image (Fig. 1A). We found whiskers of probably FeS (Fig. 1C) in some matrices as well. Magnetite
grains with different morphologies (framboidal, spherulitic, plaquette and equant) are also commonly present (Fig. 1A). Submicron grains of FeS and magnetite are usually present in the matrix. Dolomite is usually present mostly as aggregates ofeuhedral or subhedral grains (Fig. 1A) and contains minor amounts of Fe and some heavy element (possibly Mn). Aggregatesof micron-sized dolomite grains are also present (Fig. 1B). Breunerite is present as a rhombohedron in shape and have thecomposition roughly estimated as (Mg0.6Fe0.4)CO3 (Fig. 1D). CaCO3 (aragonite or calcite) is rarely present. Apatite is usuallypresent mostly as aggregates of subhedral or anhedral grains (Fig. 1E). Small grains of forsterite or enstatite (Mg#~1) arerarely observed. Small objects (mostly <1 µm) of probably organic materials are commonly present in the matrix (Fig. 1B) but
their abundance is small (probably a few % or less). Inclusions, which are empty or filled with low-Z materials, were observedin FeS, dolomite, breunerite and apatite grains (Fig. 1D). Spherical objects of phyllosilicate surrounded by fine grains of FeS

or dolomite (Fig. 1E) and object composed of Fe-rich and mostly anhydrous silicates (Fig. 1E) and fine grains of FeS and/or
magnetite named “dark inclusion” (Fig. 1A) were sometimes observed. In addition to the above phases, several unidentified
phases are observed as well. Some sample particles are unique; a low-density material (~1 g/cm3) with a lot of fine cracks andorganic-like material with embedded mineral grains. Porous objects like the ultra-porous lithology in Acfer 094 [3] were notobserved.

Figure 1. RGB-CT images of Ryugu particles(R: LAC at 7 keV = 0-950 cm-1, G: RID = 02010-6, B: LAC at 7.35 keV = 0-450 cm-1).
(A) C0103-FC007. (B) A3_MPF_X003
showing dark and bright matrices (upper andlower regions, respectively). (C)A3_MPF_X007 showing a whisker ofprobably FeS. (D) A0067-FC0003: breunerite
grain with inclusions. (E) A3_MPF_X007
having wide cracks. (F) A3_MPF_X004.

D ranges from 9 to 60 µm. The 3D shape distribution indicates that the
Ryugu particles (B/A =0. 66 and C/B =0.65 in average) are less spherical inshape than the Itokawa particles and fragments of impact experiments (c.f.,silver ratio: B/A=C/B=0.71) [1]. Some particles examined here may not be theoriginal impact fragments on the Ryugu surface but artificial fragments during
the sampling by the space craft and/or in the laboratory. Y is small (<0.4) and
FD of some particles are <3 together with a weak correlation between them,
indicating that the particle shapes are irregular and complicated. Some surfacesof the particles are convexo-concave indicating fragmentation, while some are
more or less smooth and may be formed by mechanical abrasion on the asteroid
as proposed for Itokawa particles [4]. Cracks less than a few µm in width arecommonly present in all particles except for those composed of single crystals.
Some cracks develop along the boundaries of some objects and mineral grains
Figure 2. Density, r, estimated from the(Fig. 1E), implying that they are cracks formed due to shrinkage by
averaged RID value (lower limit) and density
dehydration. Some cracks are subparallel to flattened particle surfaces
considering open pores, r∞, plotted against
open porosity, p∞.
probably due to impact (Fig. 1F). p0 is usually less than a few%. p∞ mostly
ranges from 5 to 20% (Fig. 2), which is less than the porosity of the CI
chondrite Orgueil (34.9% [5]). This can be explained by the different size of pores; the p∞ counts relatively large pores (>~afew hundred nm) while that of CI counts nanopores. r mostly ranges from 1.3 to 1.8 g/cm3 and and r∞ from 1.1 to 1.6 g/cm3(Fig. 2). They are not inconsistent with the bulk density of Orgueil (1.57 g/cm3 [5]) if we consider r and r∞ as the lower limits.
The examined samples closely resemble CI in mineralogy and textures although we did not surely find any sulfates, such as
gypsum, epsomite and blödite. The porosity and density are also consistent with those of CI. Any signature of dehydration as
suggested from the IR spectrum [6] was not recognized. Highly porous materials as expected from the low thermal inertia [7]were not observed. FIB sections were prepared based on the 3D information and examined by TEM [8, 9]. The present
examination is ongoing and we note that some of the ranges of physical properties, such as D, B/A, C/B, Y, FD, p0, p∞, r and
r∞, are still preliminary.
References[1] Tsuchiyama A. et al. 2013. Geochim. Cosmochim. Acta 116;5. [2] Takeuchi A. et al. 2014. J. Synchrotron Radiat. 20:793.
[3] Matsumoto M. et al. 2019. Science Advances 5;eaax5078. [4] Tsuchiyama A. et al. 2011. Science 333;1125. [5] Flynn G. J.
et al. 2018. Chemie der Erde 78: 269. [6] Kitazato K. et al. 2019. Science 268:272. [7] Okada T. et al. 2020. Nature 579:518.
[8] Nakamura T. et al. 2021. Abstract in this volume. [9] Noguchi T. et al. 2021. Abstract in this volume.

Surface morphologies and space weathering features of Ryugu samples
T. Matsumoto1, T. Noguchi1, A. Miyake1, Y. Igami1, M. Haruta1, H. Saito2, S. Hata2, Y. Seto3, M. Miyahara4, N. Tomioka5, H.
A. Ishii6, J. P. Bradley6, K. Ohtaki6, E. Dobrică6, T. Nakamura7, M. Matsumoto7, A. Tsuchiyama8, 9; M. Yasutake10, J.
Matsuno8, S. Okumura1, K. Uesugi10, M. Uesugi10, A. Takeuchi10, M. Sun9, S. Enju11, A. Takigawa12, H. Leroux13, C. Le
Guillou13, D. Jacob13, M. Marinova13, F. de la Peña13, F. Langenhorst14, D. Harries14, P. Beck15, T. H. Van Phan15, R. Rebois15,
N. M. Abreu16, T. Zega17, P.-M. Zanetta17, M. Thompson18, M. Lee19, L. Daly19, P. Bland20, R. Stroud21, K. Burgess21, J. C.
Bridges22, L. Hicks22, M. E. Zolensky23, D. R. Frank6, J. Martinez24, H. Yurimoto25, K. Nagashima6, N. Kawasaki25, R.
Okazaki2, H. Yabuta4, H. Naraoka2, K. Sakamoto26, S. Tachibana12, S. Watanabe27, Y. Tsuda26, and the Hayabusa2 Initial
Analysis Team1
2
3
Kyoto Univ., Japan; Kyushu Univ., Japan; Kobe Univ., Japan; 4Hiroshima Univ., Japan; 5Kochi Core Center, JAMSTEC,Japan; 6Univ. of Hawaii, USA; 7Tohoku Univ., Japan; 8Ritsumeikan Univ., Japan; 9Guangzhou Institute of Geochemistry,
China; 10JASRI, Japan; 11Ehime Univ., Japan; 12Univ. of Tokyo, Japan; 13Univ. de Lille, France; 14Univ. of Jena, Germany;
15
Univ. Grenoble Alpes, France; 16Penn State, USA; 17Univ. of Arizona, USA; 18Purdue Univ., USA; 19Univ. of Glasgow, UK;
20
Curtin Univ., Australia; 21US Naval Research Laboratory, USA; 22Univ. of Leicester, UK; 23JSC/NASA, USA; 24Jacobs
Engineering, 25USA, Hokkaido Univ., Japan; 26JAXA/ISAS, Japan; 27Nagoya Univ., Japan
Introduction: Asteroids are leftover remnants of planet formation and provide clues as to the origin and evolution of the earlysolar system. C-type asteroids have been expected to be parent bodies of carbonaceous chondrites, containing hydrated silicatesand volatile compounds that could be the origin of water and life on the Earth. JAXA’s Hayabusa 2 spacecraft explored C-type
asteroid Ryugu and collected surface materials at two landing sites on Ryugu [1]. The spacecraft delivered its re-entry capsuleto the Earth, and subsequent initial investigation of the Hayabusa 2 sample container found that millimeter pebbles and finegrains were successfully recovered from the surface of Ryugu [2]. Geologic maps and variations in the reflectance spectra of
Ryugu’s surface suggest that geologic activities and alteration of regolith occur over time [3]. Ryugu samples will provide an
opportunity to understand the dynamic evolution of surface materials on C-type asteroids. Materials exposed to the spaceenvironment are expected to have altered optical, physical, or chemical properties. This process is defined as space weathering,which includes alteration by micrometeoroid bombardments, solar wind implantation, and solar radiation heating [4]. Analysesof lunar soils and regolith particles from S-type asteroid Itokawa have revealed that the uppermost surfaces of regolith grains
record the space weathering features, such as amorphization, melting, and vapor-deposition [5,6]. Thus far, the space weatheringof carbonaceous asteroids is not well understood. The surface microstructures of Ryugu samples will offer insight into theongoing alteration of the regolith on Ryugu. In this study, we report the surface morphologies and mineral structures of Ryugu
samples investigated in the initial analysis by the Mineralogy-Petrology Fine (Sand) sub-team.
Samples and methods: Ryugu samples from the two sampling sites were preserved in chambers A and C of the sample catcher
inside the sample container [2]. We have mainly investigated the fine grains (< 300 µm) picked up from both chambers at theExtraterrestrial Sample Curation Center of JAXA. After the samples were allocated from JAXA, we handled them in a dry glove
box filled with nitrogen at Kyoto University. For surface observation, the fine grains were fixed on gold plates using an Araldite
adhesive. We examined the surface features of the Ryugu samples using a field emission scanning electron microscope (FESEM: JSM-7001F). We then extracted electron-transparent sections of regions of interest on the Ryugu grains fortransmission/scanning transmission electron microscopy (TEM/STEM) studies, using a focused ion beam (FIB) system (Helios
NanoLab G3 CX at Kyoto University, Thermo Scios at Kyushu University). We are now performing TEM/STEM analysis,
synchrotron radiation X-ray absorption fine structure analysis, nano-tomography, and atom probe analysis.
Results: Surface features of Ryugu grains: Fine Ryugu grains have massive, platy, and granular shapes. The majority of thegrain surfaces consist of phyllosilicates with rough surfaces. Coarse and fine surface textures are identified on the phyllosilicates.
Cracks/gaps exist between phyllosilicates and other mineral phases. TEM analysis shows that the phyllosilicates are composed
mainly of serpentine and saponite (detailed TEM observations are described in [7]). The second major mineral phases on thegrain surfaces are sulfides, magnetite, and carbonates. These minerals are ubiquitous, although their abundance varies from grain
to grain. Most of the sulfides are pyrrhotite crystals. They appear as hexagonal plates, cuboids, and irregular shapes with sizes
up to a few tens of micrometers. The pyrrhotite plates exhibit sharp growth steps on their surfaces. Some pyrrhotite crystals withirregular surfaces have numerous voids. Pentlandite often coexists with pyrrhotite. Tiny sulfides (< 1µm), including zinc,
chromium, and/or copper, occur as minor phases. Magnetite appears as framboidal aggregates, plaquettes, spherulites, andirregular shapes. The framboidal magnetite on Ryugu grains have distinct sharp edges, when compared to framboidal magnetites

with rounded morphologies in thermally metamorphosed CI chondrites (e.g., Y980115) in which thermal sintering has likely
occurred. The carbonate phases found on the Ryugu grains are mainly dolomite and minor magnesite-breunnerite. They haveeuhedral, fractured, and irregular surfaces. Calcium phosphate, oxides (chromite, ilmenite), and iron phosphides are found as
minor phases. Na-Mg bearing phosphate with an irregular shape is present as a rare phase and is commonly attached loosely to
the grain surfaces. Anhydrous minerals found on Ryugu grains are forsteritic olivine, low-calcium pyroxene and pure spinel withsizes up to a few micrometers. These phases are rare. Most of them have fractured surfaces.
Space weathering features: We found impact craters, melted drops, splashes, melt sheets, glassy spherules on Ryugu grains
by SEM observation (Fig. 1). Studies of lunar soils and Itokawa particles have shown that these objects are likely products of
micro-impacts on airless bodies [8, 9]; hence, the grain surfaces with the impact products may have been exposed to the spaceenvironment. The abundance of the impact products varies from grain to grain. Phyllosilicates on the grain surfaces are altered
to have smooth surface textures with tiny voids (Fig. 1 in [7]). TEM analysis shows that the uppermost surface is surrounded byan amorphous rim with a thickness from 50 nm to 2-3 µm. Tiny vesicles and iron compounds appear in the rim. EDX analysis
shows a change in chemical composition near the surface. The altered surfaces of pyrrhotite and pentlandite have shallow
depressions (200 nm – 300 nm in depth) with rugged textures (Fig. 1). Iron metals protrude from the iron sulfide surfaces, andsome are in the form of curved whiskers (Fig. 1). Dark-field TEM imaging suggests disordering of the lattice near the sulfide
surface. Carbonates and magnetite have altered surfaces with rough textures. The breunnerite grain we examined by TEM has adistinct rim with disordered lattice and a thickness of approximately 90 nm. Selected area diffraction patterns obtained from therim imply the appearance of periclase ((Mg,Fe)O) particles in the rim.
Discussion: The dominance of phyllosilicates and the scarcity of anhydrous minerals indicate that Ryugu samples haveexperienced a high degree of aqueous alteration. The morphologies of the major mineral phases, such as the unique shapes ofmagnetite, suggest a close similarity between Ryugu samples and CI chondrite [10].
Previous ion irradiation experiments simulating space weathering suggest that the uppermost surface of phyllosilicates canbe modified by space weathering [11]. The altered phyllosilicate rim found in our analysis may have been formed by solar windimplantation and impact events [7]. Iron metallic whiskers on iron sulfides have recently been identified as space weathering
products in lunar soils and Itokawa particles [12,13]. The iron metals are likely to have formed via selective sulfur loss,
accumulation of excess iron atoms, and subsequent growth of iron metals. These alteration processes may be caused by various
phenomena including solar wind implantation, thermal effects produced by micrometeoroid bombardments and solar heating[12]. The appearance of iron whiskers on Ryugu samples implies that the space weathering of iron sulfides on Ryugu is similar
to that on the Moon and Itokawa. The thickness of the altered rim on breunnerite is roughly consistent with the maximum depth
at which extensive atomic displacement is produced by implanted solar wind ions (~ 1 keV/nucleon) [6]. Hence, solar windimplantation may have contributed to the rim formation of the carbonate. Based on our initial analysis, we tentatively conclude
that the Ryugu samples record the combined processes of space weathering on the aqueously altered asteroid, implying that
remote sensing data should be reassessed considering the space weathering effect.

Fig. 1 Space weathered Ryugu grain. (a) Backscattered electron image of a fine Ryugu grain. (b-d) Secondary electron images of a melted
drop (b), pyrrhotite with an iron whisker (c), and an impact crater with a residue on phyllosilicates (d). The image (d) was obtained fromanother fine Ryugu grain. M: melted drop, Po: pyrrhotite, W: iron whisker. Triangles in (d) indicate the crater rim.

References: [1] Watanabe S. et al. 2019. Science 364, 268-272. [2] Yada T. et al. 2021. Abstract# 2548 in 52nd LPSC. [3] Sugita
S. et al. 2019 Science 364, 252. [4] Pieters C. and Noble S. K. 2016. J. Geophys. Res. Planet 121, 1865-1884. [5] Keller L. P.
and McKay D. S. 1993 Science 261, 1305-1307. [6] Noguchi T. et al. Science 333, 1121-1125. [7] Noguchi T. et al. this
symposium. [8] McKay D. S. et al. 1991. Lunar Sourcebook. [9] Matsumoto T. et al. 2018. Icarus 303, 22-33. [10] Brearley A.
2006, Meteorites and the early solar system II, 587-624. [11] Thompson M. et al. 2020. Icarus 346, 113775. [12] Matsumoto T.
et al. 2020. Nat. Commun. 11, 1-8. [13] Matsumoto T. et al. 2021. Geochim. Cosmochim. Acta 299, 69-84.

CNHOS contents with their isotopic compositions and preliminary organic profiles
from the Hayabusa2 samples
Yoshinori Takano1, Hiroshi Naraoka2, Nanako O. Ogawa1, Yasuhiro Oba3, Toshiki Koga1, Toshihiro Yoshimura1,
Saburo Sakai1, Naohiko Ohkouchi1, Hisayoshi Yurimoto3, Tomoki Nakamura4, Takaaki Noguchi5,
Ryuji Okazaki2, Hikaru Yabuta6, Kanako Sakamoto7, Shogo Tachibana7,8, Sei-ichiro Watanabe9,
Yuichi Tsuda7 and the Hayabusa2-initial-analysis SOM team
1

JAMSTEC, 2 Kyushu Univ., 3 Hokkaido Univ., 4 Tohoku Univ., 5 Kyoto Univ.,
6
Hiroshima Univ., 7 JAXA, 8 Univ. Tokyo, 9 Nagoya Univ.

The successful collection and recovery of the Ryugu sample [1,2] are leading us to a valuable opportunity for revealing theproperties of the carbonaceous asteroid in the Solar System history; -What is Ryugu? -What are the origins and characteristics
of light elements (C, N, H, O, and S)? -What do their isotopic compositions tell us? -How do they record the primordial chemical
evolution on the asteroid? -How did the interaction of water, organic matter, and minerals affect the evolution and diversity ofindigenous molecules? To answer those important issues by using state-of-the-art small-scale analysis, the SOM (Soluble
Organic Matter) team have been firstly focusing on (i) the initial bulk profiles, especially for the elemental abundance of carbon(C), nitrogen (N), hydrogen (H), oxygen (O), sulfur (S) with the isotopic compositions of δ13C, δ15N, δD, δ18O and δ34S,
respectively, and (ii) the molecular profiles to understand more deeply for nature of indigenous SOM [3-5]. For instance, if
endogenous water-mineral interactions occurred in the asteroid, some aqueous alteration signatures (e.g., process relevant
products including carbonates and other precipitates) should have been recorded to the pristine sample in the bulk and molecularlevels. Assuming the interactions above mentioned, we can trace the potential in-situ temperature of the alteration process byusing clumped isotope surveys of minerals [6]. To assess the objectives, we have been conducting rehearsal analyses foranalytical optimizations and sequential sample processes [3-5, e.g., Figure 1], with a scope of solid and soluble organic aspects[6-9]. In order to deal with samples of unknown identity, especially for bulk nitrogen scale, we validated the dynamic range ofδ15N profiles covered on the basis of pioneering works and compilations for the Inner and Outer Solar System [e.g., 10].

Figure 1 The high precision and high accuracy analytical optimization using reference standards of carbon (C), nitrogen (N),and sulfur (S) for covering wide range isotopic compositions: (a) δ13C, ‰ vs. VPDB; within 13C-enriched and 13C-depleted
profiles, (b) δ15N, ‰ vs. Air; within 15N-enriched and 15N-depleted profiles, (c) δ34S, ‰ vs. VCDT; within 34S-enriched and
34
S-depleted profiles. The x-axis and y-axis stand for the nominal value (= expected) and the measured value (= observed),
respectively. Prior to the Hayabusa2 samples, those analytical validations using the nano-EA/IRMS system [3,4,7] were
performed during the rehearsal analyses (e.g., several carbonaceous chondrite of CM2 and C2-ungrouped: unpublished data)
at JAMSTEC. We have confirmed that there was no memory effect in the analytical lines due to sequential process. For
further of optimization ultra-small-scale sulfur (S) quantification with δ34S validation, please see the latest update [11].





Figure 2 (a, b) Capturing the representative colors during the sequential solvent extraction and the wet chemical treatment
for the Hayabusa2 samples (Ryugu, sample ID: A106 & C107). After solid-liquid separation, the colored supernatant withyellowish and pinkish colors were observed in both A106 and C107, the photo taken in the cleanroom at Dept. Earth Planet
Sci., Kyushu Univ. Since dissolved inorganic elements and organic-inorganic complex molecules also have some kind ofchromaticity depending on the affinity of the solvent, we are in the process of conducting detailed verification. Please see
also the residue of insoluble organic matter (IOM, black color) on the bottom of the vial. The onsite RGB color scale is shown.

We observed some of the colored supernatant during the sequential solvent extraction processes of Ryugu sample (Figure2). These extraction samples have been safely distributed to the SOM team members and are being analyzed in detail at theirlaboratories [12]. The residue of IOM fraction has been also seamlessly transported to the other initial analysis team for further
description [13]. Here, we note that the colors of the extract show the chemical responses of the extractable indigenous organic
molecules to the inherent affinity of the solvent from low to high polarity (i.e., dependent on hydrophilicity, hydrophobicity, andamphiphilicity with both properties). Also, the colored supernatant may indicate that there is a certain amount of components
with a significant absorption spectrum (e.g., chemically various carbon skeleton with N-, S-, O-hetero structures). Regarding themolecular-level analysis, we are currently in the process of combining the pieces of the raw data profiles [12], and we expect
synergistic discussions at this symposium in terms of native organic properties within the history of the Ryugu.

References[1] Tachibana S. et al., #1289, 52nd LPSC (2021); Tachibana S. et al., Geochem. J. 48, 571-587 (2014).
[2] Yada T. et al., #2008, 52nd LPSC (2021).
[3] Naraoka H., Takano Y., Dworkin, J. P. et al., #6314, 82nd Met Soc (2019); Naraoka H. et al., #1362, 51st LPSC (2020).
[4] Ogawa N. O. et al., 51st LPSC (2020); Ogawa N. O. et al. Earth, Life, Isotopes, Kyoto Univ. Press. (2010).
[5] Yoshimura T. et al., #1971, 51st LPSC (2020); Yoshimura, T. et al. J. Chromatogr. A 1531, 157-162 (2018).
[6] Wang Z. et al., Anal. Chem. 92, 2034-2042 (2019); Bonifacie M. et al., Geochim. Cosmochim. Acta 200, 255-279 (2017).
[7] Kebukawa Y. et al., Meteorit Planet Sci. 56, 1311-1327 (2021); Kebukawa Y. et al., Geochim. Cosmochim. Acta 271, 61-77(2020); Chan H. S., et al., Earth, Planets Space, 68, 7 (2016).
[8] Oba Y. et al., Nature Commun. 10, 4413 (2019); Oba Y. et al., Nature Commun. 11, 6243 (2020).
[9] Takano Y. et al., Inter. J. Mass Spectrom. 462, 116529 (2021).
[10] Kerridge J.F. Geochim. Cosmochim. Acta 49, 1707-1714 (1985); Füri, E. and Marty B., Nature Geosci. 8, 515-522 (2015).
[11] Ogawa N. O. et al., #PR0203, Geochem. Soc. Jpn. (2021).
[12] Naraoka H., Takano Y., Dworkin, J. P., this symposium. & the other reports from the Hayabusa2-initial-analysis SOM team.
[13] Initial reports from the Hayabusa2-chemistry, -stone, -sand, -volatile, -IOM team at this symposium.

Compound distribution determined by nanoLC-Orbitrap MS
Francois-Regis Orthous-Daunay1, Cédric Wolters1, Véronique Vuitton1, Roland Thissen1, Junko Isa2, Hiroshi Naraoka3,
Hisayoshi Yurimoto4, Tomoki Nakamura5, Takaaki Noguchi6, Ryuji Okazaki7, Hikaru Yabuta8, Kanako Sakamoto9, Shogo
Tachibana9,10, Seiichiro Watanabe11 and Yuichi Tsuda9 , and the Hayabusa2-initial-analysis SOM team1

Univ. Grenoble Alpes CNRS IPAG, 2Tokyo Inst. Tech., 3Kyushu Univ., 4Hokkaido Univ., 5Tohoku Univ., 6Kyoto Univ., 7NASA
Goddard Space Flight Center, 8Hiroshima Univ., 9JAXA, 10Univ. Tokyo, 11Nagoya Univ

The Hayabusa2 mission is no less than the first opportunity to infirm or confirm theories about the formation of C-type
asteroids [1], [2]. The origin and nature of the organic molecules Ryugu bears will tell which part of this chemistry takes placeon this type of airless bodies and which part in inherited by accretion. The comparison with carbonaceous chondrite will be themethod to evaluate if what has been interpreted from well-studied meteoritical samples is still valid for actual asteroid regolith.
This study focuses on the molecular mixture complexity observed thanks to the combination of two analytical methods: liquid
phase chromatography and high-resolution mass spectrometry [3]. Samples from the first (named A106) and second (C107)
encounter with Ryugu were washed with different solvents in order to extract the soluble organic compounds in a sequence ofincreasing polarity in Kyushu University. Each extract was separated on an amide column with limited volume and flow in a
so-called nano-liquid-chromatography (nano-LC) protocol. The chemical separation is monitored through time by Orbitrapmass-spectrometry (Orbitrap-MS).
This provides three observables for each compound present in the Ryugu soil extract: an intensity evaluating its relative
abundance, a retention time depending on its structure and a molecular weight equivalent to its atomic composition. With
thousands of different compounds, mixtures usually exhibit peculiar patterns in this three-dimensional framework. For instance,
the relative abundance of phospholipids in terrestrial living cells varies by orders of magnitude if the carbon atoms number is
odd or even, making contamination by fingerprints easy to detect. We used the ATTRIBUTOR routines developed at
University of Grenoble Alpes to extract relevant patterns in the Ryugu extracts chromatograms [4].
The most remarkable feature found in both meteorites and Ryugu samples is a ubiquitous polymerization pattern [5]. Almost
each measured mass is part of a network linking it to other molecules with one more carbon atom, two more hydrogen atoms
or any combination of these. A typical bell-shaped intensity distribution indicates that the whole mixtures are likely to be of
one single synthesis origin [6]. Variability of the distribution characteristics goes with a complex origin of subsequent
processes. This type of mass and intensity patterns is difficult to find in other terrestrial natural samples.
The less polar molecules found in Murchison have extremely broad distributions, only matched by some of the Ryugu’s
compounds and other chondrites. For these molecules, the best analogues are solid residues generated out of gas mixtures inplasma chambers [7]. Experimental polymers synthesized in liquid phase or by irradiation of ices have significantly different
polymerization patterns [8].
The chemical structure of compounds found in Ryugu slightly differs from the one in the CM2 Murchison chondrite. As ofpreliminary identification, the less polar compounds are similar between Ryugu and Murchison while the most polar molecules
have significantly different retention times. Assuming polar compounds are more likely to be part of a reaction in liquid water,
the discrepancy between Murchison and Hayabusa2 samples could be due to different degree of aqueous alteration on theirparent bodies.
References[1] Tachibana, S. et al. 2021.Lunar Planet. Sci. Conf.p. 1289 [2] Yada, T. et al. 2021.Lunar Planet. Sci. Conf.p. 2008 [3]Naraoka, H.Takano, Y.Dworkin, J. P.and SOM Analysis Team. 2020.Lunar Planet. Sci. Conf.p. 1362 [4] Orthous-Daunay, F.R.Thissen, R.and Vuitton, V. Apr. 2019.Proc. Int. Astron. Union.vol. 15, no. S350.pp. 193–199 [5] Naraoka, H.Yamashita,
Y.Yamaguchi, M.and Orthous-Daunay, F. R. 2017.ACS Earth Sp. Chem.vol. 1, no. 9.pp. 540–550 [6] Orthous-Daunay, F.-R.
et al. 2019.Geochem. J.vol. 53, no. 1 [7] Bekaert, D. V. et al. 2018.Astrophys. J.vol. 859, no. 2.p. 142 [8] Vinogradoff,
V.Bernard, S. Le Guillou, C.and Remusat, L. 2017.Icarus.vol. 305.pp. 358–370

Highest molecular diversity and structural complexity revealed with ultrahigh resolution
mass spectrometry and nuclear magnetic resonance spectroscopy of Ryugu´s samples
Philippe Schmitt-Kopplin1, 2, Norbert Hertkorn2, Marianna Lucio2, Marco Matzka2, Mourad Harir2,
Philippe Diederich2, Hiroshi Naraoka3, Hisayoshi Yurimoto4, Tomoki Nakamura5, Takaaki Noguchi6,
Ryuji Okazaki3, Hikaru Yabuta7, Kanako Sakamoto8, Shogo Tachibana8,9, Seiichiro Watanabe10 and Yuichi Tsuda8
and the Hayabusa2-initial-analysis SOM team1

Technische Universität Muenchen, Germany, 2 Helmholtz Zentrum Muenchen, Germany,3
Kyushu Univ., Japan, 4Hokkaido Univ., Japan, 5Tohoku Univ., Japan, 6Kyoto Univ., Japan,
7
Hiroshima Univ., Japan, 8JAXA, Japan, 9Univ. Tokyo, Japan, 10Nagoya Univ., Japan.

The surface and possible sub-surface materials of the asteroid Ryugu were recovered during the two touch-down
sampling by the Hayabusa2 spacecraft. Here we present the first results on the solvent soluble organic matter (SOM)
using ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectroscopy (FTICR/MS) complemented
with high field nuclear magnetic resonance spectroscopy (NMR) [1-3]. The two samples A106 (first touchdown) andC107 (second touchdown) were sequentially extracted in the Hayabusa2-initial-analysis SOM team with various polar
and apolar solvent extracts and demonstrate a never seen molecular complexity and diversity.
We confirm herewith the close similarity and the possible comparison of the solvent extracts with meteoritic
material to the Hayabusa2 return samples. We analyzed the sequential hexane, dichloromethane (DCM), methanol
and water extracts with NMR and with electrospray ionization (ESI) and atmospheric pressure photoionization (APPI)[4] FTICR/MS systematically for both negative and positive ions. The hundred thousands of signals were filtered,converted and assigned into more than 24,000 elementary compositions consisting of carbon (C), hydrogen (H),nitrogen (N), oxygen (O) and/or sulfur (S). Organomagnesium compounds (CHOMg, CHOSMg) were not found andthis reflects the low temperature processes on the parent body [5, 6]. As shown for carbonaceous chondrites previously,
our results confirm that the extraterrestrial chemical diversity is much higher compared to terrestrial biological andbiogeochemical spaces and consists in a regular continuum (i) of small to macromolecules (ii) of carbon oxidation
states from apolar (CH, polycyclic aromatic hydrocarbons and branched aliphatics) to polar small molecules (CHO)
with increasing functionalized oxygen and heteroatom contents (CHN, CHS, CHNO, CHOS) leading to the observed
differential solvent type solubility. We revealed specific known molecular targets (CHN+, CHNO+) [4] and show
evidences of multiple chemosynthesis pathways in describing the carbon oxidation state distribution and heteroatom
contributions to the assembly of multiple complex endogen molecules; these also reflect cold hydrothermalism
involved on the parent body [5,6]. We also confirm the high importance of chemical processes involving specificnitrogen and sulfur chemistry [7, 8]. The two fractions analyzed show an extreme coverage in structural features in
APPI and only slight differences in the apolar solvents in ESI. The A106 sample showed slight differences only withhigher mass range and more oxygenated compounds. The C107 sample had increased abundance and uniqueness ofmore unsaturated carbon and low oxygenated compounds that may have disappeared due to surface processing (somehypothesis could be cosmic irradiation at the surface). These samples presents a unique opportunity of having a direct
and low invasive insight into the complex organic diversity present on 162173 Ryugu.

Figure 1. Selected results from the analysis of the solvent extracts of A106 (24159 formula) and C107 (23250 formula) analyzed
with Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) in electrospray ionization negative mode (ESI(-))
and atmospheric pressure photoionization (APPI(+)). (A) nominal mass 319 details of dichloromethane (DCM) extracts of the CM2
Aguas Zarcas, A106, C107 and the DCM-blank with the annotated elementary compositions as CH, CHO and CHNO fromultrahigh resolution. (B) counting of the thousands of elementary compositions in the C, H, O, N, S space as obtained from ESI(-)
and APPI(+) and there abundance variations within the different extraction solvents for the A106 and C107 samples. (C)visualization of the structural information retrieved from the elementary compositions as van Krevelen diagram plots describing
the differences in oxygenations between the two ionization modes ESI(-) and APPI(+) and the profiles of the non-oxygenated CH,
CHS and CHN compounds.

References[1] Schmitt-Kopplin, P. et al. 2010. Proc. Natl. Acad. Sci. U.S.A., 107:2763. [2] Ruf, A. et al. 2018. Life 8:18. [3]Hertkorn, N. et al. 2015 Magn. Reson. Chem., 53:754. [4] Herzog J. et al. 2019. Life, 9:48. [5] Ruf. A. et al. 2017 Proc.
Natl. Acad. Sci. U.S.A., 2017, 114:2819. [6] Matzka, M. et al. 2021. Astrophys. J. Lett., 915:L7. [7] Danger, G. et al.
2021. Nat. Commun., 12:1. [8] Danger, G. et al. 2020. Planet. Space Sci., 1:55.

The Winchcombe Meteorite: A Pristine Sample of the Outer Asteroid Belt
Ashley J. King1, Luke Daly2, Katie H. Joy3, Helena C. Bates1, James F. J. Bryson4, Queenie H. S. Chan5, Patricia L. Clay3,
Hadrien A. R. Devillepoix6, Richard C. Greenwood7, Sara S. Russell1, Martin D. Suttle7 & the Winchcombe Consortium
1
Natural History Museum, London, 2University of Glasgow, 3University of Manchester, 4University of Oxford,
5
Royal Holloway, University of London, 6Curtin University, 7The Open University (a.king@nhm.ac.uk)
At 21:54 (UT) on the 28th February 2021 a bright fireball was observed travelling approximately W to E over theUnited Kingdom. The fireball lasted ~7 seconds and was recorded by 16 stations operated by the six meteor camera networksof the UK Fireball Alliance (UKFAll); it was also caught on numerous dashboard and doorbell cameras and there were >1000
eyewitness accounts, including reports of a sonic boom. Following an appeal in the national media, the main mass (~320 g) of
the meteorite was discovered by a family in Winchcombe, Gloucestershire. The stone landed on the family’s driveway,
shattering into a pile of dark mm- to cm-sized fragments and powder, most of which they collected wearing gloves and sealed
within plastic bags ~12 hours after the fall. Further meteorites were recovered in the local area over the following week bymembers of the public and during an organised search by the UK planetary science community, with the largest piece being a
152 g fusion-crusted stone found on the 6th March 2021 on farmland. In total, >500 g of the Winchcombe meteorite wasrecovered less than seven days after the fall, with no significant rainfall having occurred during that time.
The entry velocity of the Winchcombe meteoroid was ~14 kms-1 and the videos clearly show several fragmentation
events in the atmosphere. Preliminary analysis of the video footage combined with the measurement of short-lived cosmogenic
radionuclides suggest that the original body was small (<100 kg). The calculated pre-atmospheric orbit of the Winchcombemeteoroid suggests an origin in the outer asteroid belt; the orbit is similar to those previously reported for the Sutter’s Mill (C)and Maribo (CM2) meteorites, but distinct from Tagish Lake (C2ung) and Flensburg (C1ung) [1−4].
Inspection of stones and fragments “by-eye” and petrographic observations of 18 polished samples by optical andelectron microscopy indicate that Winchcombe is a CM (“Mighei-like”) carbonaceous chondrite. It consists of chondrules andcalcium-aluminium-rich inclusions (CAIs) set within a matrix (SiO2 ~28 wt%, FeO ~24 wt%, MgO ~18 wt%, total ~80 wt%)of phyllosilicates, carbonates, magnetite and sulphides. X-ray diffraction (XRD) analysis of several fragments show that thephyllosilicates are a mixture of Fe- and Mg-bearing serpentines present at >80 vol%. Many of the polished samples, plus mmsized chips characterised using computed tomography (CT), show evidence for brecciation and contain multiple distinct
lithologies with sharp boundaries. Most lithologies record a high degree of aqueous alteration (CM2.0 – 2.2 on the Rubin et al.
[5] scale); chondrules and CAIs retain well preserved fine-grained rims (FGRs) but have been extensively replaced bysecondary minerals including abundant tochilinite-cronstedtite intergrowths (TCIs) and carbonates. A rare lithology containing
unaltered chondrules and metal has also been identified. The sulphides are mainly pyrrhotite and pentlandite, and magnetite
typically has a framboidal structure. Several large (~50−100 µm) sulphate grains have been found embedded within the matrix,
with their textural setting suggesting that they formed from a fluid on the parent body.
The classification of Winchcombe as a CM chondrite is further supported by bulk major and minor element
abundances and oxygen (δ17O = 2.75 & 0.94; δ18O = 9.48 & 7.29; Δ17O = -2.18 & -2.85) and titanium isotopic compositions.
The bulk water content of Winchcombe is ~12 wt% and analysis of two chips by stepped combustion yielded carbon (~2.0wt%) and nitrogen abundances and isotopic compositions consistent with other highly altered CM chondrites [e.g. 6]. The
release profiles indicated the presence of multiple carbon- and nitrogen-bearing organic components and low voltage SEM
characterisation of unprepared chips less than a week after the fall identified several carbon-rich regions with “globule-like”
morphologies. However, initial analysis by gas chromatography-mass spectrometry (GC-MS) suggests that the total aminoacid abundance in Winchcombe is significantly lower than in most CM chondrites [e.g. 7].
The Winchcombe meteorite is only the fifth carbonaceous chondrite fall with a known pre-atmospheric orbit, and due
to its rapid recovery is likely the most pristine member of the CM group. The mineralogical, elemental, and organic properties
of Winchcombe provide a snapshot of conditions in the protoplanetary disk and new insights into the chemical and dynamic
evolution of volatiles in the early solar system. The nature of the Winchcombe meteorite and timing of the fall makes itcomplementary to samples of asteroids Ryugu and Bennu collected by the Hayabusa2 and OSIRIS-REx missions, offering an
opportunity to develop and rehearse analytical protocols on fresh, carbonaceous materials.
References: [1] Jenniskens et al. (2012) Science 338:1583. [2] Borovička et al. (2019) M&PS 54:1024. [3] Brown et al. (2000)
Science 290:320. [4] Borovička et al. (2021) M&PS 56:425. [5] Rubin et al. (2007) GCA 71:2361. [6] Alexander et al. (2013)
GCA 123:244. [7] Glavin et al. (2006) M&PS 41:889.

Thermal History of Dehydrated CY Chondrites Reconstructed from their Fe-sulfide Grains
Catherine S. Harrison1,2, Ashley J. King1, Rhian H. Jones2 and Tobias Salge1
Department of Earth Sciences, Natural History Museum, London, SW7 5BD, UK
2
Department of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK
1

Introduction: Following low temperature (<200 ℃) aqueous alteration, the CY carbonaceous chondrites experienced
significant post-hydration heating (>500 ℃) on their parent body, evidenced by dehydrated phyllosilicates, secondary
recrystallized olivine, the destruction and modification of organics, low water contents, and melting of Fe-sulfides [e.g., 1-4].
However, the timing, duration and mechanism of this heating is currently poorly defined. Constraining the thermal history of the
CY chondrites is an important step to understanding the evolution of the water-rich C-complex asteroids, and the distribution
and transport of volatiles in the early solar system. Our studies also provide a framework for interpreting the samples returned
from Ryugu, as the initial results of JAXA’s Hayabusa2 mission suggest that materials on Ryugu record periods of both aqueous
and thermal alteration [5].
Sulfides are widespread in the carbonaceous chondrites and are sensitive to both aqueous alteration and thermal
metamorphism. The unheated CM and CR chondrites contain primary and secondary Fe-sulfides that can provide a detailed
record of the conditions within the nebula prior to accretion, as well as aqueous alteration on the parent bodies [6-9]. The CY
chondrites contain a third generation of sulfides, specifically pyrrhotite ([Fe,Ni]1-xS) containing inclusions of pentlandite([Fe,Ni]9S8), that formed from the cooling of a monosulfide solid solution (MSS, [Fe,Ni] 1-xS) during the metamorphic event[e.g., 6, 7]. Experimental work on synthesized MSS compositions has shown that the textural features and compositions of thesesulfides are diagnostic of their cooling histories [10-12].
Here, we have systematically characterized the pyrrhotite-pentlandite grains within the matrices of CY chondrites ofheating stages III (peak temperature 500-700 ℃) and IV (peak temperature >750 ℃) [13], to infer their thermal history.
Samples and Methods: We have characterized up to 20 coarse (>40 µm) sulfide grains within each of five CY
chondrites: Yamato (Y-) 82162 and Y-86029 (both Stage III [2]), Y-86789 and Y-86720 (likely paired, Stage IV [2, 14]), andBelgica (B-) 7904 (Stage IV [2]). Scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) has been
carried out at 20 kV and 1.5 nA for one polished section of each sample using a ZEISS Evo 15LS SEM equipped with an Oxford
Instruments Aztec EDS system at the Natural History Museum (NHM). To improve the spatial EDS resolution to the submicrometre scale, one grain in B-7904 was analysed at 6 kV using an FEI Quanta field emission SEM and Bruker annular EDS
detector at the NHM.
Results: The sulfide grains can be separated into two assemblage types - pyrrhotite containing inclusions of pentlandite(PoPn), and pyrrhotite containing inclusions of both pentlandite and metal (PoPnM). Table 1 summarizes the number of grains
belonging to each assemblage type, the average nickel content of the pyrrhotite and pentlandite, and the typical size of thepentlandite and metal inclusions. Within each sample, the pentlandite inclusions are commonly associated with cracks in thepyrrhotite, and occasionally occur as isolated blebs within the pyrrhotite grains. In Y-82162, the pentlandite inclusions areoriented laths, whereas in Y-86029, Y-86720, Y-86789 and B-7904 they are irregular in shape and randomly oriented. The
PoPnM grains are only present in the Stage IV meteorites Y-86720, Y-86789 and B-7904, and can contain both Ni-rich (up to
56 wt% Ni) and Ni-poor (<6 wt% Ni) metal inclusions (Figure 1). In B-7904 the metal inclusions are anhedral and typically <5µm in size, although the largest inclusion is ~20 µm in size. In Y-86720 and Y-86789 the metal inclusions are irregular in shapeand tend to form along the outer edge of the sulfide grains. Large area elemental EDS mapping of complete sections show thatthe paired meteorites Y-86789 and Y-86720 both contain a sulfide-rich and a sulfide-poor lithology. All analysed grains within
the sulfide-rich lithology are PoPnM type, while in the sulfide-poor lithology they are PoPn type.
Table 1. Properties of the Fe-sulfide grains in Stage III and IV CY chondrites.
Sample (section Heating No. of PoPn No. of PoPnM
Avg. Po Ni
Avg. Pn Ni
number)Stage
grainsgrainscontent (wt%)
content (wt%)
Y-82162 (45-1)
III11
0.15 ± 0.10 [106]14.9 ± 1.9 [74]Y-86029 (51-A)
III
10
0.15 ± 0.04 [57]12.1 ± 2.3 [58]B-7904 (64-A)IV
70.18 ± 0.08 [38]14.7 ± 1.4 [17]Y-86720 (59-A)IV
9
11
0.13 ± 0.04 [52]14.4 ± 2.4 [15]Y-86789 (81-A)IV
8
80.11 ± 0.07 [61]15.0 ± 1.8 [46]Typical Pn
inclusion size
<5 µm
<5 µm
<15 µm<12 µm<10 µmTypical M
inclusion size

<5 µm
<10 µm<10 µmPo = pyrrhotite, Pn = pentlandite, M = metal, No. = number. Avg. = average. The number of data points for the average Ni contents are inparentheses.

Discussion: Annealing experiments on synthesized MSS compositions show a sequence of pentlandite exsolution
textures that evolve with time, where the final morphology of the pentlandite is largely dependent on the cooling rate [10-12].
The quickest cooling rates (<10 K/hr) produce irregular and randomly oriented pentlandite inclusions, while slower cooling rates(>100 K/hr) result in oriented blades/lamellae of pentlandite [11]. The oriented laths of pentlandite within Y-82162 suggest thatthe sulfides within this sample experienced a slower cooling rate in comparison to those observed in Y-86029, B-7904, Y-86720
and Y-86789. If impacts were the source of heat, this possibly suggests that Y-82162 samples a deeper layer of insulating regoliththan the other CY chondrites. Alternatively, Y-82162 might originate from the surface of a parent body that orbited sufficiently
close to the sun for solar radiation to keep temperatures elevated for a longer period of time [15]. However, other factors suchas the peak metamorphic temperature and the initial MSS composition (metal:S ratio and Fe:Ni ratio) also affect the final
pentlandite abundance and morphology. While the experimental work of [10-12] is useful for estimating relative cooling rates
between meteorite samples, the ranges of sulfide compositions and environmental conditions considered in these studies are notdirectly comparable to those on the parent body(ies) of the CY chondrites. For example, the experimental work did not produce
any metal-bearing sulfide grains like those observed in Y-86720, Y-86789 and B-7904. It has been suggested that the Fe,Nimetal inclusions formed through the thermal decomposition of pentlandite and pyrrhotite at temperatures >610 ℃ under reducing
conditions at an fS2 near the iron-troilite buffer [7, 16], but the influence of the metal inclusions on the texture and morphologyof pentlandite requires further experimental work.
Kimura et al. [6] and Harries and Langenhorst [7] alsostudied the sulfides within Y-86720 (section 71-3 and fragment 86,
respectively) and B-7904 (section 94-1 and fragment 114,
respectively). In both samples, they only identified metal-bearing
sulfide grains that lacked pentlandite (i.e. PoM grains). In contrast,
we observed only PoPnM grains within B-7904, and identified two
different lithologies within Y-86720 and Y-86789 that containeither PoPnM or PoPn grains. This is consistent with thesemeteorites being breccias and suggests that the different lithologies
each experienced different thermal histories. Based on the thermal
decomposition of pentlandite into Fe,Ni-metal with higher
temperatures [7, 16], we suggest a decreasing order of peakmetamorphic temperature between the lithologies to be PoM >PoPnM > PoPn. Evidence for heterogeneous heating among thedifferent lithologies could explain variable estimates for peakmetamorphic temperatures within the literature. For example,
estimates for Y-86720 range from 500 ℃ [17] up to 850 ℃ [18],Figure 1. EDS net intensity map of a PoPnM sulfide grain inwhile for B-7904 they vary between 400 ℃ [19] and 900 ℃ [18].
B-7904. (6V, 890 pA, 319 kcps, 1680x1680 pixels, 50 nm
Heterogeneous heating within the CY chondrites could
pixel size, 129 min). Fe – green, Ni – red, S – blue.
result from highly localized variations in the metamorphic
conditions. Alternatively, the PoM lithology might have been heated to a greater extent than the PoPn lithology during themetamorphic event, before impacts mixed different lithologies to form a heterogeneous breccia. It is also possible that the
primary and/or secondary sulfides within each lithology were compositionally very different prior to heating.
Summary: There are differences in the textural features of the sulfide grains and their associations with Fe,Ni-metal
among each of the CY samples, and also among different lithologies within the samples. This suggests the CY chondrites
experienced varied thermal histories. Deciphering the cause of these differences will allow us to further develop thermal models
for hydrous asteroids.
References: [1] Ikeda (1992) Proc. NIPR Symp. Antarct. Meteorites 5:49. [2] King et al. (2019) Geochem 79:125531.
[3] Tonui et al. (2014) GCA 126:284. [4] Quirico et al. (2018) GCA 241:17. [5] Kitazato et al. (2019) Science 364:272. [6]Kimura et al. (2011) M&PS 46:431. [7] Harries and Langenhorst (2013) M&PS 48:879. [8] Schrader et al. (2015) M&PS 50:15.
[9] Singerling and Brearley (2020) M&PS 55:496. [10] Durazzo and Taylor (1982) Miner Deposita 17:313. [11] Kelly andVaughan (1983) Mineral. Mag. 47:453. [12] Etschmann et al. (2004) Am. Mineral. 89:39. [13] Nakamura et al. (2005) J. Min.
Petrol. Sci. 100:260. [14] Matsuoka et al. (1996) Proc. NIPR Symp. Antarct. Meteorites 9:20. [15] Chaumard et al. (2012) Icarus
220:65. [16] Harries (2018) Hayabusa Symposium (abstract). [17] Zolensky et al. (1993) GCA. 57:3123 [18] Akai (1992) Proc.
NIPR Symp. Antarct. Meteorites 5:120. [19] Zolensky et al. (1991) Proc. NIPR Symp. Antarct. Meteorites 16:195.

Hydrothermal history of (162173) Ryugu’s parent body inferred from remote-sensing data
Eri Tatsumi1,2,3, Naoya Sakatani4, Lucie Riu5, Moe Matsuoka5, Rie Honda6, Tomokatsu Morota3, Shingo Kameda4, Tomoki
Nakamura7, Michael Zolensky8, Rosario Brunetto9, Takahiro Hiroi10, Sho Sasaki11, Sei’ichiro Watanabe12, Satoshi Tanaka5,13,
Jun Takita14, Cédric Pilorget9, Julia de León1,2, Marcel Popescu15, Juan Luis Rizos1,2, Javier Licandro1,2, Ernesto Palomba16,
Deborah Domingue17, Faith Vilas17, Humberto Campins18, Yuichiro Cho3, Kazuo Yoshioka3, Hirotaka Sawada5, Yasuhiro
Yokota5, Masahiko Hayakawa5, Manabu Yamada19, Toru Kouyama20, Hidehiko Suzuki21, Chikatoshi Honda22, Kazunori
Ogawa5, Kohei Kitazato22, Naru Hirata22, Naoyuki Hirata23, Yuichi Tsuda5,13, Makoto Yoshikawa5,13, Takanao Saiki5, Fuyuto
Terui5, Satoru Nakazawa5, Yuto Takei5, Hiroshi Takeuchi5,13, Yukio Yamamoto5,13, Tatsuaki Okada5,3, Yuri Shimaki5, Kei
Shirai23, Fernando Tinaut1,2, Sunao Hasegawa5, Seiji Sugita3,191
Instituto de Astrofisica de Canarias (etatsumi-ext@iac.es), 2Dept. Astrophysics, Univ. La Laguna, 3The University of Tokyo,
4
Rikkyo University, 5Institute of Space and Astronautical Science (ISAS), 6Kochi University, 7Tohoku University, 8NASA
Johnson Space Center, 9Université Paris-Saclay, CNRS, Institut d’Astrophysique Spatiale, 10Brown University, 11Osaka
University, 12Nagoya University, 13SOKENDAI, 14Hokkaido Kitami Hokuto High School, 15Astronomical Institute of the
Romanian Academy,16INAF, Instituto di Astrofisica e Planetologia Spaziali, 17Planetary Science Institute, 18University ofCentral Florida, 19Planetary Exploration Research Center,, Chiba Institute of Technology, 20National Institute of Advanced
Industrial Science and Technology, 21Meiji University, 22The University of Aizu, 23Kobe University.
1. Summary
Small rubble pile asteroids record the thermal evolution of their much larger parent bodies. However, recent space
weathering and/or solar heating create ambiguities between the uppermost layer observable by remote-sensing and the pristinematerial from the parent body. Hayabusa2 remote-sensing observations find that on the asteroid (162173) Ryugu both northand south pole regions preserve the least space-weathered material, which is spectrally blue carbonaceous chondritic material
with a 0 – 3% deep 0.7-µm band absorption, indicative of Fe-bearing phyllosilicates [1]. We report that spectrally blue
Ryugu’s parent body experienced intensive aqueous alteration and subsequent thermal metamorphism at 570 – 670 K (300 –400 ˚C), suggesting that Ryugu’s parent body was heated by radioactive decay of short-lived radionuclides possibly because of
its early formation 2-2.5 Ma. The samples being brought to Earth by Hayabusa2 will give us our first insights into this epoch insolar system history. Moreover, we found the NUV-VIS spectral similarity between Ryugu and Polana–Eulalia family
members, suggesting plausible origin from inner main belt predicted by the dynamical simulation [2].
2. Observation on polar regions
Ryugu could be an ideal body to study the thermal history and water/rock ratio of pre-disruption parent bodies, muchlarger (~100 km) than Ryugu. Our objective is to find the most pristine material on Ryugu and to study evidence for proposed
thermal metamorphism of its original parent body and consequent processes after its catastrophic disruption and reaccumulation. Stratigraphic analyses have suggested that the possible surviving, unprocessed materials are bluer than the
average Ryugu reflectance spectrum [3,4]. Slightly bluer materials than the average were found on the equatorial ridge, whichmight be uncovered by regolith migration from the ridge to the middle latitudinal regions. Furthermore, the global observations
obtained by the Hayabusa2 spacecraft discovered that the bluest materials are distributed at the polar regions of Ryugu [3].
This motivated us to conduct detailed surveys of the polar regions to investigate the unprocessed materials. Effects after theformation of Ryugu, such as solar wind irradiation, micrometeoroid bombardment, and radiative heating caused by close
encounter to the Sun, need to be deconstructed.
Spectrally blue (negative visible spectral slope) material is concentrated on both poles, as clearly shown. Furthermore,
blue material is associated with a relatively deeper 0.7-µm band absorption. Phyllosilicates in CM/CI chondrites become
progressively enriched in Mg (and depleted in Fe) as aqueous alteration proceeds [5]. Thus, Fe-bearing phyllosilicates showing
0.7-µm band absorption are a strong indication of the specific water/rock ratio condition during the parent body formation. To
examine the cause of the distribution of blue materials with 0.7-µm band absorption, the maximum temperature in anasteroidal year and the normalized solar photon dose were calculated based on the TIR measurements [6], the shape model andcurrent orbital elements. The comparison indicates that areas and facets with low solar wind irradiation fluxes exhibit blue
spectra and relatively deeper 0.7-µm absorption, while the influence of solar heating does not clearly correlate with the spectral
characteristics. On the north pole, the concentration of the material with blue spectral slope, and deeper 0.7-µm band
absorption were well correlated with the regions experiencing the lowest temperatures and least solar wind irradiation due tothe large incidence angle during the whole asteroidal year. The correspondence between the color variation and thoseprocesses shows that solar wind irradiation is a more likely cause for the color changing from blue to red and the decrease in
the 0.7-µm band absorption depth
3. Possible connection with (3200) Phaethon(3200) Phaethon, the target of the DESTINY+ Mission, exhibits blue spectra in the visible wavelength range and turn-up
in the UV. Recently, many ground-based observations were made over a wide wavelength range, which reported that thevariation in visible spectral slope depends on rotational phase. The range of spectral slope variation in one rotation is -0.5 to
0.05 µm-1 and that of the relative R-band magnitude is ± 0.15 [7,8]. Moreover, a correlation between brighter and bluer spectra
was also observed [7]. The similarity for both Ryugu and Phaethon, that neither exhibits a strong UV nor 2.7-µm OH-band
absorption for the entire rotational phases [9], might result in similar spectral changes due to space weathering on both
asteroids. Thus, the majority of Phaethon’s surface could be explained by freshness due to rejuvenation caused by the recent
encounter with the Sun, i.e. fresh cometary activity.
4. Search for F types in the main belt
Ryugu is an F-type asteroid with a flat spectral shape in near-ultraviolet (0.4 – 0.55 µm) [10]. In order to put in context
the results from the Hayabusa2 spacecraft and of its returned sample analyses, it is critical to know the abundance of F-types
across the Solar System. However, after Eight Color Asteroid Survey (ECAS) [11], there is no major spectroscopic survey thatcovers the near-ultraviolet wavelength range. We started ground-based near-ultraviolet observations using telescopes at Roquede Los Muchacho Observatory, La Palma, Spain. Also we revisited our previous observations and reanalyzed the data in thiswavelength range. We collected the spectral data of Themis, Polana, and Eulalia family members from our observations and
ECAS. The largest members of these families are known to have negative visible spectral slope. Polana and Eulalia families
are the plausible origin of Ryugu based on the dynamical calculation [2]. When we compared only the visible slope, thosefamily members cannot be distinguished. However, if we use near-ultraviolet spectral slope, Themis family members are quite
different from Polana and Eulalia family members. While Themis members show deep absorption in near-ultraviolet, Polana
and Eulalia members exhibit flatter in this region. Ryugu is consistent with variation of the Polana and Eulalia members.
Moreover, Bennu, the target asteroid of NASA’s OSIRIS-REx [12], is also consistent with the Polana and Eulalia group. We
found the connection between Ryugu and Polana and Eulalia members spectroscopically. Thus, now the idea that Ryugu isoriginated from the inner main belt is supported also from spectroscopy.
References[1] Tatsumi, E. et al. 2021. Nature Commun. [2] Campins, H. et al. 2013. ApJ 146:26. [3] Sugita, S. et al. 2019. Science 364.
eaaw0422. [4] Morota, T. et al. 2020. Science 368. 654. [5] McAdam, M. M. et al. 2015. Icarus 245. 320. [6] Shimaki et al.
2020. Icarus 348. 113835. [7] Ohtsuka, K. et al. 2020. PSS 191. 104940. [8] Kareta, T. et al. 2018. ApJ 156. 6. [9] Takir, D. et
al. 2020. Nature Commun. 11. 2050. [10] Tatsumi, E. et al. 2020. A&A 639. A83. [11] Zellner, B. et al. 1985. Icarus 61. 355.
[12] Lauretta, D. S. et al. 2019. Nature 568. 55.

Multiband thermal radiometry and related laboratory studies, indicating
possible origin and evolution of Ryugu
M. Hamm1,2, M. Grott2, H. Senshu3, J. Knollenberg2, J. de Wiljes1, V. E. Hamilton4, F. Scholten2, K. D. Matz2, H. Bates5,6, A.
Maturilli2, Y. Shimaki7, N. Sakatani8, W. Neumann2,9, T. Okada7, F. Preusker2, S. Elgner2, J. Helbert2, E. Kührt10,11, T.-M. Ho12,
S. Tanaka7, R. Jaumann13,2, S. Sugita14
1

Institute of Mathematics, University of Potsdam, Potsdam, Germany, 2Institute of Planetary Research, German Aerospace
Center (DLR), Berlin, Germany, 3Planetary Research and Exploration Center, Chiba Institute of Technology, Narashino,
Japan, 4Southwest Research Institute, Boulder, CO USA, 5Department of Earth Sciences, Natural History Museum, Cromwell
Road, London, SW7 5BD UK, 6Atmospheric, Oceanic and Planetary Physics, Oxford University, Parks Road, Oxford, OX1
3PU, UK, 7Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan,
8Department of Physics, Rikkyo University, Toshima, Japan, 9Universität Heidelberg, Heidelberg, Germany, 10Institute of
Optical Sensor Systems, German Aerospace Center, Berlin, Germany, 11Qian Xuesen Laboratory of Space Technology, China
Academy of Space Technology, Beijing, China, 12German Aerospace Center (DLR), Institute of Space Systems, Bremen,
Germany, 13Freie Universität Berlin, Berlin, Germany, 14University of Tokyo, Bunkyo, JapanThe MASCOT lander’s radiometer [1] observed the diurnal variation of the surface temperature of single boulder on thesurface of (162173) revealing a low thermal inertia and high porosity [2]. While the instrument observes the surface throughsix filters, two broad band filter and four bands pass transmitting the region between 6 and 16 µm, only the data of the 8 – 12µm broadband filter was used in the previous studies [2, 3]. Coupling a thermophysical model to a combined DEM of boulder
and landing site [4], and applying a data assimilation scheme for efficient parameter estimation [2], the analysis of the fullradiometer data becomes feasible. The thermal inertia and emissivity of the surface within the filter’s spectral ranges could be
retrieved. The thermal inertia is estimated to be 255 – 265 J m-2 K-1 s-1/2, corresponding to a high porosity of 46 ± 1 %. The
emissivity in the broad filters is estimated to be 0.98 ± 0.1.
The emissivity estimates in the narrowband filters shows significant differences from band to band. In the 5.5 – 7 µm band theemissivity drops to band to 0.85 (-0.02, +0.01), reaches its maximum in the 8 – 9.5 µm band with 0.98 ± 0.01, drops in theadjacent 9.5 – 11.5 µm band to 0.94 (-0.02, +0.01), and rises again to 0.97 ± 0.01 in the 13.5 – 15.5 µm region. We form theratios of the emissivity within the 9.5-11.5 µm band and the 13.5 – 15.5 µm band with respect to the emissivity within the 8 9.5 µm band and compare them to equivalent emissivity ratios of mid-infrared spectra of powdered and thin section samples ofvarious carbonaceous chondrites. We find that respective ratios of aqueously altered CM and CI chondrites form a common
trend and our results for Ryugu lies within this cluster of CM and CI chondrites. The CI chondrites appear to be the best
spectral match in the mid-infrared. Our study indicates that despite the partially dehydrated appearance of the surface in thevisible to near-infrared wavelength range [5,6,7], the mid-infrared shows strong signs of aqueous alteration, and the Ryugu
materials might be less dehydrated than previously thought.

References[1] Grott, M., et al., 2017, Space Science Reviews, 208, 413–431. [2] Grott, M., et al., 2019, Nature Astronomy, 3, 971 – 976.
[3] Hamm, M., et al., 2020, Monthly Notices of the Royal Astronomical Society, 496, 3, 2776-2785. [4] Scholten, F., et al.,2019, Astronomy & Astrophysics, 632, L5. [5] Sugita, S., et al., 2019, Science, 364. [6] Kitazato, et al., 2019, Scienceeaav7432. [7] Kitazato, et al., 2021, Nature Astronomy, 5, 246–250.

Color Mapping of Asteroid Bennu
D.N. DellaGiustina1 and the OSIRIS-REx Science Team
1
Lunar and Planetary Laboratory, University of Arizona
To evaluate relationships between color and morphology on Bennu, we radiometrically and photometrically corrected
multispectral images acquired by the MapCam instrument of the OSIRIS-REx Camera Suite (OCAMS) [1-4]. Calibrated
images were subsequently mosaicked to develop band-ratio and principal component analysis (PCA) maps. We mapped ~1600
boulders and ~700 craters, extracted their average MapCam spectra, and examined statistically meaningful trends between
color, reflectance, and these morphological features. We also compared the global color distribution of Bennu to that of Ryugu.
The color of the largest craters (>100 m) on Bennu is indistinguishable from that of the average terrain. However,many small (≤25 m) craters are redder than average in the visible to near-infrared wavelengths (VIS to NIR; MapCam b′ to x
bands; neutral to red spectral slopes). The size distribution of these small reddish craters implies that they are the youngest
component of the global crater population, in turn implying that redder colors are related to younger exposure ages [4]. We
interpret this finding to indicate that space weathering leads to spectral bluing on Bennu [4].
On the basis of reflectance and color, we have categorized Bennu’s boulders into four types [4]: 1) Dark boulders areequivalent to or darker than Bennu’s average surface, are subangular, and commonly have rough, undulating surface textures.
They encompass a wide range of sizes including the largest boulders on the asteroid (25 to 100 m in diameter) and are thedominant boulder type. 2) Bright boulders are brighter than the average surface of Bennu, have blue spectral slopes in the midVIS to NIR (MapCam v to x bands), and exhibit smooth, typically angular textures. They occur only at diameters less than ~10m. 3) Rare, very bright boulders (reflectance up to 0.26; ~1% in number) show evidence of an absorption at 1 μm (downturn inthe x band), which was confirmed to be indicative of exogenic pyroxene using data acquired by the OSIRIS-REx Visible andInfraRed Spectrometer (OVIRS) [5]. 4) Rare boulders (~2% in number) that have an absorption feature detectable above the
OCAMS radiometric uncertainty at 0.7 μm (absorption depth of 2 to 10%) are inferred to contain Fe-bearing phyllosilicates.
The 0.7-μm absorption has been observed in spectra of primitive asteroids and carbonaceous meteorites and has been attributed
to the Fe2+-Fe3+ intervalence charge transfer associated with hydrated clay-bearing phyllosilicates [5].
This variety of boulders indicates that Bennu’s surface is highly diverse, encompassing primitive material potentiallyfrom different depths in its parent body [4], as well as exogenic material delivered to the parent body from another asteroid
family [5].
The multi-band cameras onboard the Hayabusa2 and OSIRIS-REx spacecraft use similar photometric filters in thevisible wavelengths, allowing for direct comparison of the spectra from each [1, 6]. The variation in reflectance on Bennu is
1.7 times that on Ryugu, and Bennu exhibits a bluer overall color [4]. Ryugu shows large-scale latitudinal color differences,which have been attributed to regolith migration from the equator to mid-latitudes during a period of rotational deceleration [6].
A latitudinal color trend is also observed on Bennu, but the difference is small compared with its overall color variation [4].
Bennu’s slightly bluer equatorial region may indicate the presence of more mature material, which is consistent with its
increasing rotation rate and the associated global patterns of mass movement across the asteroid [7]. Unlike Ryugu, color
variation on Bennu appears to be dominated by heterogeneity at the meter scale, likely driven by individual boulders [4]. Thissuggests that the extent of recent large-scale mass wasting on Bennu may not have been as widespread as the effect of regolith
mixing [4].
References[1] Rizk, B., et al. "OCAMS: the OSIRIS-REx camera suite." Space Science Reviews 214.1 (2018): 26. [2] Golish, D. R., et al.
"Ground and in-flight calibration of the OSIRIS-REx camera suite." Space Science Reviews 216.1 (2020): 12. [3] Golish, D.
R., et al. "Disk-resolved photometric modeling and properties of asteroid (101955) Bennu." Icarus (2020): 113724. [4]DellaGiustina, D. N., et al. "Variations in color and reflectance on the surface of asteroid (101955) Bennu." Science 370.6517(2020). [5] DellaGiustina, D. N., & Kaplan, H. H., et al. “Exogenic basalt on asteroid (101955) Bennu”. Nature Astronomy,(2021): 5.1. [6] Sugita, S., et al., “The geomorphology, color, and thermal properties of Ryugu: Implications for parent-bodyprocesses”. Science (2019): 364. [7] Jawin, E. R., et al., “Global patterns of mass movement on asteroid (101955) Bennu”.
JGR Planets, (2020):125.

The Mineralogy and Organic Composition of Bennu as
Observed by VNIR and TIR Spectroscopy
V. E. Hamilton1, A. A. Simon2, H. H. Kaplan2, P. R. Christensen3, D. C. Reuter2, D. N. DellaGiustina4, C. W. Haberle5, L. B.
Breitenfeld6, B. E. Clark7, and D. S. Lauretta4
1Southwest Research Institute, Boulder, CO, USA (hamilton@boulder.swri.edu)
2NASA Goddard Space Flight Center, Greenbelt, MD, USA
3Arizona State University, Tempe, AZ, USA
4University of Arizona, Tucson, AZ, USA
5Northern Arizona University, Flagstaff, AZ, USA
6Stony Brook University, Stony Brook, NY, USA
7Ithaca College, Ithaca, NY, USA

NASA's Origins, Spectral Interpretation, Resource Identification, and Security — Regolith Explorer (OSIRIS-REx) mission
characterized the surface composition of the carbonaceous asteroid Bennu at visible to infrared wavelengths (~0.4 - 100 µm).
Spectral features of hydrated minerals (phyllosilicates) are dominant at both visible to near infrared (VNIR) [1, 2] and thermal
infrared (TIR) wavelengths [1], with ~90 vol.% of the silicates being comprised of phyllosilicates (≤~10 vol.% olivine plus
pyroxene) [3]. Features of iron oxides are observed in both the VNIR (magnetite, goethite) [4] and the TIR (magnetite) [1]. In
the 3.2-3.6 µm region, we observe spatially variable evidence for carbonate minerals (some associated with meter-long, cmwide veins) and organic compounds comparable to insoluble organic material (IOM), with classification results showing little
or no evidence of any correlation between these features and surface morphology or spectral slope/band depth [5-9]. A halfdozen isolated, meter-sized boulders exhibit pyroxene signatures consistent with those in the howardite-eucrite-diogenite(HED) meteorites from (4) Vesta [10]. There is evidence for non-uniform deposits of dust (~5-10 µm thick) superposed on alargely boulder-dominated surface [3]. The majority of VNIR features show only small band depth variations across the surface [4] and the TIR features appear to vary dominantly with particle size [3]. Nanophase magnetite produced by space weathering may account for Bennu’s visible blue slope [12]. Two populations of rocks are observed in visible imaging, distinguishedby albedo and surface texture [11], but spectral data analyzed to date have not shown any evidence of these two populations
having different compositions.
The observed mineralogy of Bennu has been identified as being most consistent with a highly aqueously altered, CI- or CMlike, carbonaceous chondrite (CC) composition. In addition, we have recently recognized that GRO 95577 (CR1) also exhibits
NIR and TIR spectra that are compatible with the observed spectroscopy and inferred mineralogy of Bennu (Figures 1 and 2).
(We note that none of the NIR analogues shown here are good matches to Bennu at visible wavelengths, where the best fit is toa sample of Ivuna (CI) heated to 700°C [14]; however, the effects of space weathering on Bennu are not represented by theanalogue spectra.) Isolated boulders containing pyroxene are interpreted as exogenic, basaltic material from Vesta, the preserved evidence of inter-asteroid mixing that occurred after the conclusion of planetesimal formation [10]. The manifestationof carbonate veins at scales much larger than has been observed in CC meteorites suggests that Bennu’s parent body experienced fluid flow and hydrothermal deposition on kilometer scales for thousands to millions of years [6]. In October 2020,
OSIRIS-REx collected a sample of the surface of Bennu for return to Earth in September 2023. We predict that the returned
sample will contain the minerals and compounds described here (phyllosilicates, iron oxides, carbonates, and organics), representing a significant degree of alteration. In addition, minerals that are difficult to detect with remote sensing data, such as sulfides, also may be present, as well as exogenous materials.
References[1] Hamilton, V. E. et al. 2019. Nature Astronomy 4:332. [2] Praet, A. et al. 2021. Icarus 363:114427. [3] Hamilton, V. E. et al.
2021. Astronomy & Astrophysics 650:A120. [4] Simon, A. A. et al. 2020. Astronomy & Astrophysics 644:A148. [5] Simon, A.
A. et al. 2020. Science 370:eabc3522. [6] Kaplan, H. H. et al. 2020. Science 370:eabc3557. [7] Kaplan, H. H. et al. 2021. Astronomy & Astrophysics 653:L1. [8] Barucci, A. et al. 2020. Astronomy & Astrophysics 637, L4. [9] Ferrone, S. et al. 2021.
Icarus 368:114579. [10] DellaGiustina, D. N. et al. 2020. Nature Astronomy 5:31. [11] DellaGiustina, D. N. et al. 2020. Science 370:eabc3660. [12] Trang, D. et al. 2021. Planetary Science Journal 2:68. [13] Takir, D. et al. 2013. Meteoritics & Planetary Science 48:1618. [14] Clark, B. E. et al. 2011. Icarus 216:462.

Figure 1. OVIRS spectrum of Bennu [1] in the “3Bennuµm region” as compared to spectra of CC

Reflectance (offset and scaled)

meteorites from [13] and a RELAB spectrum of
GRO 95577.

GRO 95577 (CR1)

Ivuna (CI1)

LAP 02277 (CM1)

MET 00639 (CM2)

Cold Bokkeveld (CM2)

2.4

8

2.6

2.8
3.0
Wavelength (µm)

3.2

3.4

Wavelength (µm)
10 12 15 20 25
Figure 2. OTES spectrum of Bennu [3]as compared to CC analogues. The

Emissivity and 1-R (offset and normalized)

Christiansen feature (~1090 cm-1, ~9.2µm) is not particularly diagnostic.
Bennu T1 (least dusty)
Orgueil (CI1)
GRO 95577 (CR1)
Almahata Sitta 91A_1 (C1)
Moapa Valley (CM1)
ALH 83100 (CM1/2)
LAP 02277 (CM2.0)
LAP 031166 (CM2.1)
ALH 85013 (CM2.2)
Cold Bokkeveld (CM2.2)
Murray (CM2.4/2.5)
Murchison (CM2.5)

1200 1000 800 600-1Wavenumber (cm )400

However, the peak at 528 cm-1 (18.9 µm)
is a diagnostic feature in the Bennu
spectrum, and it weakens and shifts withincreasing abundances of anhydrous
silicates (e.g., pyroxene and olivine). As
the abundance of anhydrous silicatesincreases, the Si-O bending mode (theminimum at ~440 cm-1 or 22.7 µm)
broadens and features of pyroxene andolivine become apparent (e.g., Cold
Bokkeveld, Murray, Murchison).

The Nature of Extraterrestrial Amino Acids in Carbonaceous Chondrites and Links to Their
Parent Bodies
Daniel P. Glavin1, José C. Aponte1,2, Jason P. Dworkin1, Jamie E. Elsila1, Hannah L. McLain1,2, and Eric T. Parker1
1
NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
2
Catholic University of America, Washington, District of Columbia 20064, USA
Meteorites and samples returned from asteroids and comets provide an important record of the physical and chemical
processes that occurred in the early solar system and represent some of the oldest solid materials currently available forlaboratory analyses. The delivery of organic matter by extraterrestrial material to the early Earth could have been an importantsource of complex prebiotic organic molecules available for the emergence of life. Analyses of primitive carbonaceouschondrites over the last five decades have revealed a major insoluble organic component [1,2], as well as a complex and highly
diverse suite of soluble organic molecules of prebiotic importance [3,4] that includes carboxylic acids, N-heterocycles, sugars,
amino acids, amines, and many other organic molecules that have not yet been identified [5]. Amino acids continue to be a
primary focus of many soluble organic analyses in carbonaceous chondrites because (1) these molecules are essential
components of life (as the monomers of proteins), (2) they have structural diversity (multiple possible isomers) that can beused to help constrain formation mechanisms and parent body conditions, and (3) most amino acids identified in carbonaceouschondrites are chiral, a property that can be used to distinguish between amino acids of extraterrestrial and terrestrial origins.
The degree of parent body hydrothermal alteration has been shown to have a major influence on the formation and destructionof amino acids in carbonaceous meteorites as observed in the measured abundances and molecular distributions [6]. Aqueousalteration in primitive asteroids could have also led to the preferential enrichment of some left-handed amino acids over theirright-handed forms, an astounding discovery that suggests that the origin of life on Earth or elsewhere was biased toward lefthanded amino acid homochirality [7,8]. This talk will give an overview of what is known about the amino acid composition ofcarbonaceous chondrites, present some key unanswered questions, and discuss how the analysis of samples returned fromasteroids Ryugu and Bennu will further advance our understanding of parent body chemistry and potential contributions fromcarbonaceous asteroids to the origin of life on Earth or elsewhere.
References[1] Alexander, C.M.O’D. et al. 2007. Geochimica et Cosmochimica Acta 71: 4380. [2] Yabuta, H. et al. 2007. Meteoritics andPlanetary Science 42: 37. [3] Glavin D.P., Alexander, C.M.O’D., Aponte, J.C., Dworkin, J.P., Elsila, J.E., and Yabuta, H.
2018. The origin and evolution of organic matter in carbonaceous chondrites and links to their parent bodies, in Primitive
Meteorites and Asteroids, ed. N. Abreu, Elsevier, pp. 205-271. [4] Furukawa, Y. et al. 2019. Proceedings of the National
Academy of Sciences USA 116: 24440. [5] Schmitt-Kopplin, P. et al. 2010. Proceedings of the National Academy of Sciences
USA 107: 2763. [6] Elsila, J.E. et al. 2016. ACS Central Science 2: 370. [7] Cronin, J. R. and Pizzarello, S. 1997. Science 275:
951. [8] Glavin, D.P. et al. 2020. Chemical Reviews 120: 4616.

Oxygen isotopes and water in bulk matrix of CM2 Murchison as an analog for Ryugu matrix
Aditya Patkar1, Trevor Ireland2, Janaina Avila3, and Michael Zolensky4
RSES, Australian National University, Australia 0200 (aditya.patkar@anu.edu.au); 2SEES, University of Queensland,
Australia 4067; 3GCSCR, Griffith University, Australia 4111; 4ARES, NASA JSC, Houston (TX), USA

1

Introduction: Fine-grained phyllosilicates like serpentine and saponite form a dominant component in CM and CI
chondrites. The triple oxygen isotope composition of the matrix phases in carbonaceous chondrites (CC) is poorly
characterised due to their small grain size and the unavailability of suitable standards for SIMS analysis. CM chondrites may
be considered as a good analog for the materials from the C-type asteroid Ryugu [1]. Since Ryugu samples are observed to bealmost entirely made of matrix material like CI chondrites, it is essential to characterise in situ bulk matrix isotope composition
using SIMS in Ryugu and the matrix-rich CCs.
Samples and methodology: We measured triple oxygen isotopes and water in the ‘bulk’ matrix of CM2 Murchison using
the Sensitive High Resolution Ion Microprobe Stable Isotope (SHRIMP SI) at RSES, Australian National University. A chip of
the rock was mounted in Bi-Sn alloy, a new mounting technique developed to measure trace amounts of water in nominallyanhydrous minerals (NAMs). In this case it is also useful in the measurement of oxygen isotopes to avoid contamination from
epoxy in the porous CC matrix in high-precision analyses. 16O-, 17O- and 18O- ions were measured in multi-collection modeusing Faraday cups followed by 16O1H peak characterisation from automated mass scans on the same spots. A spot size of 30µm was used. The measurements were referenced to San Carlos Olivine (SCO). An antigorite serpentine reference material
was also analysed to establish any issues with the OH– peak tailing under 17O–.
Results: Triple oxygen isotope analysis in 27 spots from Murchison matrix
were acquired. The observed range in the isotope ratios are Δ17O ≈ +1 to +7‰(mean 2SE at 95% confidence ≈ 0.21‰), δ17O ≈ +2 to +7‰ (mean 2SE ≈ 0.5‰),
δ18O ≈ -3 to +5‰ (mean 2SE ≈ 0.25‰). External reproducibility of Δ17OSCO was≈ 1‰. Any instrumental mass fractionation effects are expected to affect δ17O
and δ18O but not Δ17O. The water abundance (16O1H/16O ratios) ranges from0.025 to 0.06, and so is significantly larger than 17O-. Figure 1a shows the plot of
16 1
O H/16O vs Δ17O.
We also measured water in olivine grains scattered in the Murchison matrix.
The apparent 16O1H/16O ratios in the Murchison olivines vary from 6 x 10-6 to 9 x
10-6. Additionally, the 16O1H/16O ratios in SCO span the same range of ~6 x 10-6
to 9 x 10-6. Calibration using multiple reference materials shows a water
concentration of ~10-15 ppm in Murchison olivines as well as SCO [2].
Discussion: There is a distinct lack of studies characterising in situ CC matrix
oxygen isotope compositions. One analysis of isolated Murchison matrix fraction
using BrF5-catalysed extraction of oxygen from silicates has yielded δ18O =12.70‰, δ17O = 4.72‰, Δ17O = -1.88‰ [3]. This analysis is isotopically‘heavier’ than the whole-rock values for Murchison but lies on the same 2component mixing line as the host rock. The Δ17O range observed in this work is≈ 2 to 8‰ higher than the analysis reported in [3]. This disparity may bepotentially related to the tailing of the OH- peak under 17O- peak due to theirsimilar mass [4]. A 100 µm collector slit on SHRIMP SI and optimum peaktuning ensures good separation of the two ion species seen in figure 1b. However,in case of an interference, OH counts/sec should be proportional to the tailing
effects, i.e., a rise in δ17O. Compared to the R2 = 0.82 value for 16O1H/16O vs
Δ17O in figure 1a, correlation with δ17O shows R2 ≈ 0.3. Can the positive Δ17O
values be trusted? The covariation seen in water vs Δ17O agrees with the two-a)b)

Figure 1: a) Plot of 16O1H/16O vs Δ17O in
Murchison matrix. 10% uncertainty is
assumed for the water ratios; b) Mass scanin Murchison matrix showing wellresolved 17O- and 16OH- peaks. Verticalline through the peaks is the position of themagnet during data acquisition.

component mixing model between a solar reservoir and heavy water reservoir for variable water : rock ratios [3]. More work isunderway to constrain the nature of these in situ measurements and ascertain any instrumental artefacts.
The water observed in the Murchison olivines stands in contrast to the elevated water concentrations from chondrule olivines
in CM chondrites reported in recent studies, and the difference is likely due to different sample preparation methods [5,6].
Water in olivines from different meteorites and Ryugu would be crucial to constrain the formation conditions of the olivinesthat make up a majority of the chondrules and are scattered throughout the CC matrix.
Conclusions: CM Murchison matrix should be a good analog for the matrix from Ryugu samples. In situ bulk matrix
analysis of CM Murchison using SHRIMP SI yield a Δ17O range of +1 to +7‰, which is at least 2‰ higher than the wholerock isotope composition range for CM chondrites. There is good covariation between the water content measured in the 27
spots and the Δ17O values. If there is any interference of the OH- ion species into 17O-, the covariation should be strong for δ17O
values too. However, that is not the case. A more robust dataset measuring matrix from other hydrous CCs like CI and CR
chondrites is needed to constrain the nature of these in situ bulk matrix measurements. Moreover, water in the NAM olivinefrom Murchison chondrules and matrix show ~10-15 ppm water which is in contrast to recent studies and has implications on
the formation and evolution of their host components.
Acknowledgements: This work is supported by an Australian Research Council Discovery Project (DP210101798) grant to
Trevor Ireland and Michael Zolensky.
References: [1] King, A. et al. (2019) M&PS, 54(3), 521-543; [2] Turner, M. et al. (2015) JAAS, 30, 1706-1722; [3] Clayton,
R. and Mayeda, T. (1999) GCA, 63(13-14), 2089-2104; [4] Ireland, T. (2013) Treatise on Geochemistry, 15, 385-409; [5]Stephant et al. (2017) GCA, 199, 75-90; [6] Azevedo-Vannson et al. (2021) 52nd LPSC, abstract #2548.

Anomalous and ungrouped carbonaceous chondrites in the US Antarctic meteorite collection andtheir potential relevance to Ryugu and Bennu
Kevin Righter1, Nicole G. Lunning1, Catherine M. Corrigan2, and Timothy J. McCoy2
1
Mailcode XI2, NASA Johnson Space Center, Houston, TX 77058
2
Smithsonian Institution, Department of Mineral Sciences, Washington, DC 20560
With two different carbonaceous asteroid sample return missions in full swing, attention has focused on what connections canbe made between the asteroid samples and the wide range of carbonaceous chondrite meteorites in worldwide collections.
The US Antarctic meteorite collection contains nearly 1000 carbonaceous chondrites of various types including many in wellestablished groups as well as ungrouped, unusual or anomalous groups [1]. Some of the latter have been included in, or are
possibly related to, recently proposed new carbonaceous chondrite classifications – CA and CY chondrites [2,3]. In addition
to these, there are numerous ungrouped samples that have properties intermediate between established groups (like CM andCO; [4]), distinct from any other groups [5], or have anomalous properties that might be attributable to parent body processes
such as heating, fluid interaction, or impacts [6].
Some CM anomalous or ungrouped chondrites share spectral features with Ryugu, which has a small hydration peakarguably due to hydrated minerals left after either impact heating or shock in carbonaceous chondrites [7]. PCA 91008, PCA
02012, GRO 95566, and LEW 85311 are all CMs that have experienced heating or metamorphism that may be due to impacts,
solar radiation, or radiogenic decay [6]. These samples all have low H contents, C/H (bulk), and low '17O [6,8] and may holdclues to understanding the mineralogy of Ryugu, or interpretations of its spectral properties.
WIS 91600, on the other hand, appears to be related to several other highly altered CM [6], and shares properties with
the newly proposed CY chondrites [6]. An understanding of this grouplet will also aid in the interpretation of Bennu samples
which have strong hydration features. In addition, ungrouped carbonaceous chondrites may provide valuable insights into theaqueous alteration potentially recorded in Bennu and Ryugu samples; such as the relatively moderate aqueous alteration
recognized and dated at 4-5 myr after CAIs in MAC 88107 (C2-ungrouped) by [9] to the extensive aqueous alteration apparent
in MIL 090292 (C1-ungrouped) [10].
Finally, LON 94101/94102 is a brecciated CM chondrite with numerous lithologies. Its appearance is similar tosome of the brecciated lithologies visible at the surface of Bennu and Ryugu [11]. Although CM chondrites with multiple
lithologies are common (e.g., [12]), the lithologies are often difficult to resolve at the hand specimen scale and only after somedetailed e-beam characterization are the subtle lithologic differences evident (e.g., [13]). LON 94102 contains visibly distinct
clasts at the hand specimen scale, relatively rare for CM breccias.
The largest CM chondrites by mass from the U.S. Antarctic meteorite collection may provide insights into the extent
of brecciation and heterogeneity within more typical CM chondrite-like source asteroids. For example, recent curation CT
scans [14] show possible clasts within in a subsplit of ALH 83100 (CM1/2) which is the largest CM chondrite or CM chondrite
pairing group in the U.S. Antarctic collection with an original mass of 3.019 kg. Similar work on additional subsplits or
meteorites may aid our understanding of heterogeneity within CM chondrites from Antarctica.
Initial classification of CM chondrites in the U.S. Antarctic meteorite collection includes preliminary pairing whenpetrographically similar CM chondrites that have been previously found in the same field area. The two largest CM chondrite
preliminary pairing groups by mass are the ALH 83102 (CM2) pairing group with an original mass of 2.554 kg and the EET
96005 (CM2) pairing group with an original mass of 1.125 kg. However, preliminary pairing groups assigned atclassification—intrinsically—do not include stones that are petrographically distinct. Rigorous pairing group studies of CM
chondrites from specific field sites are needed to investigate if there is unrecognized heterogeneity in CM chondrites from
Antarctica that may represent common asteroid impactors (pre-atmospheric entry asteroids/meteoroids). Detailed pairingstudies have the potential to recognize initial stones with multiple lithologies and investigate if there are stones that only
sample one of those respective lithologies in the collection.
These groups of heated CMs, extensively hydrated CMs, intermediate between CM and CO chondrites, and brecciatedsamples are all potentially relevant to Bennu and Ryugu samples, where heating, hydration, and brecciation have all come intoplay. These bodies might also be comprised of material intermediate to CM and CO chondrites, or at least distinct from thewell-established CC groups. These small and unusual groups of carbonaceous chondrites may help to unlock new
information about early solar system processes and aid in the understanding of the evolution of these carbonaceous asteroids.

References[1] https://curator.jsc.nasa.gov/antmet/index.cfm. [2] King AJ et al. (2019) Geochemistry 79: 125531. [3] Kimura M et al.
(2021) Meteoritics & Planetary Science, in press. [4] Prestgard T et al. (2021) Meteoritics & Planetary Science 56, 1758–1783.
[5] Davidson J et al. (2020) LPSC 51st, #1623. [6] Choe WH et al. (2010) Meteoritics & Planetary Science 45: 531-554. [7]Kitazato K (2019) Science 364: 272-275. [8] Alexander CMD et al. (2018) Space Science Reviews 214: 1-47. [9] Doyle PM etal. (2015) Nature Communications 6, 1-10. [10] Jilly-Rehak C et al. (2018) Geochimica et Cosmochimica Acta 222, 230-252[11] Walsh K et al. (2019) Nature Geoscience 12: 242-246. [12] Zolensky et al. (2020) Meteoritics & Planetary Science 56:
49-55. [13] Telus M et al. (2019) Geochimica et Cosmochimica Acta 260, 275-291. [14]https://curator.jsc.nasa.gov/antmet/samples/petdes.cfm?sample=ALH83100

VOLATILES IN CHONDRITES AND ACHONDRITES
M. Bose1, T. M. Hahn2, Ziliang Jin3
1
School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287
2
Jacobs, Johnson Space Center, Houston, TX 77058
3
Macau University of Science and Technology, Macau.
(*Correspondence: Maitrayee.Bose@asu.edu)

The abundance and distribution of volatiles in Solar System objects are vital for understanding planet
formation and evolution. The presence of water and organic molecules is critical for the emergence of life
and the habitability of planetary environments. Although some information on volatiles can be obtained
from analysis of meteorites, they are prone to alteration and exchange in Earth’s environment. Additionally,lack of context, i.e., which specific asteroid body, sampling location within the asteroid etc. results in an
incomplete understanding. Returning samples allows for the use of state-of-the-art laboratory analyses,
providing extremely high-precision, high-sensitivity, and high-resolution. More importantly, returned
samples can be placed into geologic context and provide complementary information with other studies ofthe parent object.
A successful sample return mission from asteroid Itokawa by JAXA’s Hayabusa spacecraft led to our
excellent understanding about the parent bodies of ordinary chondrite meteorites. Minute details of theasteroid’s history was gleaned through thorough and detailed laboratory investigations including
compositions, mineralogy, and chronology. One such investigation led to the measurement of hydrogenisotopes and water in tiny Itokawa particles, which show that the silicate minerals can contain between 400800 ppm of water and translated to up to 0.5 Earth’s oceans to be delivered to proto-Earth by S-type
asteroids1. On the other hand, the proportions of various chondritic materials accreted to form Mars are
distinct from those for Earth. Recent accretion models for terrestrial planets using chondritic components
suggests that S-type asteroids (specifically, H chondrites) would have contributed up to 50% the mass ofproto-Mars2. Based on analysis of recent confirmed falls, Chelyabinsk and Benenitra, we ascertained that
only about ½ of water contained within the martian mantle can be explained by accretion of S-type
asteroids; We speculate that pebble accretion may have played a significant role in forming Mars3.
Asteroids Bennu and Ryugu are the targets of ongoing sample return missions from C-type asteroids. The
spectral features are similar to those of aqueously altered CM-type carbonaceous chondrites (CCs).
Murchison and Aguas Zarcas are CM2 chondrite falls and potential meteorite analogs for Bennu and Ryugu.
We studied these two CCs and their components to constrain the evolution of hydrogen in C-type asteroids4.
In addition, we studies stones from Ureilites and Brachinites5, primitive achondrites that are likely better
planet forming starting materials because of their early accretion ages. I will discuss the data, and discuss
how both chondrites and achondrites that formed in the inner solar system could be the source of volatiles
during the early accretion stages of terrestrial planets.
References.
(1) Jin Z. and Bose M. (2019) Science Advances 5:eaav8106.
(2) Mah J. and Brasser R. (2021) Icarus 354: 114052(3) Jin Z. and Bose M. (2020) LPS XXXXI, Abstract #1470.
(4) Bose M., Hahn Jr. T. M., and Jin Z. (2021) 84th Annual Meeting of the Meteoritical Society, Abstract#6078.
(5) Bose M., Hahn Jr. T. M. (2021) 84th Annual Meeting of the Meteoritical Society, Abstract #6227.

Space weathering of sulfides and silicate minerals from asteroid Itokawa
Laura Chaves1, Michelle Thompson1
1
Purdue University
Space weathering refers to the progressive spectral, microstructural, and chemical alterations of mineral grains on the surfacesof airless planetary bodies [1]. These changes are produced by high-velocity micrometeoroid impacts and solar wind irradiation,
causing vesiculation, melt and vapor deposits, sputtering, ion implantation, and amorphization on regolith grains. Spectrally,
space weathering produces multiples alterations in the visible near-infrared (VNIR) wavelengths, including reddening,
darkening, and attenuated absorption bands [1]. The spectral anomalies have been attributed to the presence of Fe nanoparticles(npFe) that are mainly composed of metallic iron (npFe0). Analyses on individual lunar grains show that the spectral alterationsin the VNIR depend on the particle size, where npFe with diameters < 5 nm produce reddening, whereas particles >10nm produce
darkening [2]. In 2010, the Japan Aerospace Exploration Agency (JAXA) Hayabusa mission successfully collected 1534 regolithparticles from the surface of S-type asteroid Itokawa [3]. Prior to sample return, S-type asteroids were hypothesized to be theparent bodies of ordinary chondrites; however, the spectral characteristics of the meteorites in our collections differed from theseasteroids. Geochemical analyses in Itokawa particles indicated a composition similar to LL4-LL6 chondrites [3], corroborating
the link between ordinary chondrites and S-type asteroids and demonstrating the importance of space weathering studies for
accurate characterization of asteroidal surfaces.
Previous studies have identified space weathering features in Itokawa regolith particles, including disordered rims, chemicallydistinct layers, whisker-like structures, sulfur depleted rims, and Fe0 and FeS nanoparticles [4,5,6,7,8]. Most space weatheringstudies have concentrated on understanding the response of silicate minerals to interplanetary space [4,9,10] as these phases are
the most common in lunar samples and Itokawa particles. However, our understanding of the behavior of other minerals underspace weathering conditions is still in a very early stage. Among these understudied minerals are sulfides which are present in
the sample collection of asteroid Itokawa [11] and are relevant minerals in carbonaceous chondrites [12], thought to be meteoritic
counterparts of asteroids Bennu, Ryugu, and Psyche [13,14,15].
To compare the responses of silicates and sulfides under space weathering conditions, we performed coordinated analyses of the
RC-MD01-0025 Itokawa grain previously identified to contain olivine, low-Ca pyroxene, and Fe-Ni- sulfides. We embedded
the particle in low-viscosity epoxy and prepared electron transparent thin sections with an approximate thickness of 50 nm usinga Leica EM UC7 ultramicrotome. To identify microstructural and chemical properties associated to space weathering in silicate
and Fe-Ni- sulfide grains in the Itokawa particle, we used a FEI Talos 200 KeV transmission electron microscope (TEM) coupledwith a Super –X silicon drift detector (SDD) energy-dispersive X-ray spectrometer (EDS). The sample preparation of the Itokawa
particle and the electron microscopy analyses of the ultramicrotomed samples were performed at Purdue University.
Bright-field (BF) TEM imaging shows the presence of a ~50 nm mottled rim in an olivine grain (Fig. 1a). Chemically, EDS
maps show the rim presents three layers (Fig. 1b,c). Layer 1 (L1) thickness is ~30 nm and shows similar O, Mg, Fe, and Si
concentrations as the bulk grain. Layer 2 (L2) has a thickness of 5-10 nm and presents depletion of Mg, Fe, and enrichment of
Si compared to L1. Layer 3 (L3) has a thickness of 5-10 nm and is Si depleted compared to L1 and L2; it is enriched in Fe andMg compared to L2 but depleted in these elements compared to L1. High resolution (HR) TEM images show an amorphous
region in the rim's outer 5-10 nm with some nanocrystalline regions. The nanocrystalline domains present d-spacing values of
0.20 nm that correspond to npFe0. Metallic iron nanoparticles were previously identified in silicates and Fe-sulfides in Itokawa
regolith particles [4,5]. The identification of chemically distinct layers in returned samples [4,6,7] and in H+ irradiation
experiments on olivine [16] suggests this multilayer rim might correspond to a combination of sputtering, redeposition, and ion
irradiation damage processes.
High resolution (HR) TEM imaging of the Fe-Ni- sulfide grain shows d-spacing values of 0.28 nm similar to (222) pentlandite
and the presence of a ~5-10 nm rim that presents nanocrystallinity (Fig. 2a). EDS mapping shows that the rim is depleted in Ni
and S but enriched in Fe compared to the bulk mineral (Fig. 2b,c). Previous studies in Itokawa samples have identified sulfurdepleted rims Fe-sulfides [5,17], and the origin of these rims is attributed to solar wind damage. The depletion in S and Ni andthe enrichment of Fe of the rim suggest it might have formed in a complex process of sputtering and redeposition. The
microstructural and chemical characteristics in the olivine and pentlandite grains further indicate that solar wind irradiation isthe main contributor to the space weathering of both mineral phases. Future work will include the TEM and EDS analyses of the
low-Ca pyroxene grains present in the RC-MD01-0025 regolith particle. In addition to TEM and EDS, we will perform electronenergy-loss spectroscopy (EELS) to compare the oxidation state of Fe between the mineral grains and the space weathered rims.
Understanding how different mineral phases respond to space weathering conditions using returned samples is crucial toaccurately interpret remote sensing observations of the surfaces of airless bodies and adequately characterize the regolith samples
collected from asteroids Ryugu and Bennu.

Figure 1. Space weathered rim on olivine grain. a) Bright field (BF) TEM image shown the ~50 nm mottled rim on olivine. b)
High-angle annular dark field image overlain with EDS maps (O, Mg, Si, Fe). c) EDS line scan showing the chemical layeringof the rim.

Figure 2. Space weathered rim on Fe-Ni- sulfide grain. a) High-resolution (HR) TEM showing the presence of a 5-10
nanocrystalline rim. b) High-angle annular dark field (HAADF) image overlain with EDS maps of S, Fe, and Ni. c) EDS line
scan showing the Ni and S depletion on rim compared to the bulk mineral.

References[1] Hapke B. 2001. Journal of Geophysical Research 106, 10039-10073. [2] Keller L. P. 1998. 29th Lunar and Planetary Science
Conference. Abstract #1762. [3] Nakamura T. et al. 2011. Science 333, 1113-1116. [4] Noguchi T. 2011. Science 333, 11211125. [5] Keller. L. P. et al. 2014. Earth, Planets and Space 66:71. [6] Thompson. M. S. et al. 2014. Earth, Planets, and Space
66:89. [7] Noguchi. T. et al. 2014. Meteoritics & Planetary Science 49, 188-214. [8] Matsumoto T. et al. 2020. Nature
Communications 11, 1-8. [9] Keller L. P. and McKay D. S. 1997. Geochimica et Cosmochimica Acta, 61, 11, 2331-2341. [10]Loeffler M. J. et al. 2016. Meteoritics and Planetary Science 51, 2, 261-267. [11] Nakamura T. et al. 2011. Science 333, 11131116. [12] Bland A. et al. 2004. Meteoritics & Planetary Science 39, 3-16. [13] Clark B. E et al., 2011. Icarus 216, 462-475. [14]Kitazato K. et al. 2019. Science 364, 272-275. [15] Elkins-Tanton L. T. Journal of Geophysical Research 125, 1-23. [16]Laczniak D. L. et al. 2021. Icarus 364, 1-23. [17] Burgess K. D. and Stroud R. M. Meteoritics and Planetary Science 56, 11091124.

Space weathering of iron sulfides on airless bodies

1

Toru Matsumoto1
The Hakubi Center for Advanced Research, Kyoto University

Introduction: Solar wind implantation, micrometeorite impacts, and solar radiation cause the alteration of the optical, physical,
and chemical properties of surface materials on airless bodies. Space weathering refers to these alteration processes, which affectrocks and soils on airless surfaces over time [1]. Microstructures indicative of space weathering are important in understanding
geological processes occurring in the dynamically evolving regolith, such as regolith motion, volatile distribution, andreplenishment of soils [2]. Space weathering features also shed light on the evolution of solids in interstellar environments andat the surface of the proto planetary disk, where free-floating particles could be bombarded by energetic ions. Extensive studies
of lunar soils and particles from S-type asteroid Itokawa have revealed microproducts caused by space weathering, such as vapor
depositions, partly/completely amorphized rims, and nanophase iron/iron compounds [e.g., 3, 4]. Our knowledge of space
weathering has progressed based on analyses of the major constituents of rock forming minerals such as silicates and oxides,
whereas the behavior of other minerals in space-exposed environments remains poorly investigated. Iron sulfides represent solid
reservoirs of sulfur, which is a major, moderately volatile element in early solar system materials. The space weathering featuresof iron sulfides will provide clues to understanding the evolution of sulfur compounds and the distribution of sulfur on airlessbodies. Here, the author reports recent studies on space weathering of iron sulfides in lunar soils and Itokawa particles using
electron microscopy techniques [5, 6].
Methods: Itokawa particles and lunar mare soils from Apollo 11 and 17 landing sites were used in the studies. The sizes of thesamples are smaller than 200 µm. Itokawa particles have mineral components corresponding to those of LL chondrites, andcontain 2 vol% of iron sulfides [7]. Lunar mare basalts include < 1 wt% of iron sulfides, with the sulfur content being higher inmare basalts than in highland rocks [8]. Surface structures of iron sulfides were observed using scanning electron microscopy(SEM). Then, electron-transparent sections were prepared using focused ion beam (FIB) systems from regions of interest on thesamples. The sections were analyzed using transmission electron microscopy (TEM).
Results: SEM observations revealed that altered surfaces of iron sulfides have vesicular textures and elongated iron metals(whiskers) on their surfaces (Fig. 1). These microstructures were identified in Itokawa particles and lunar soils and are similar
to each other. TEM analysis showed that the upper zone of iron sulfides from the surface to a depth of up to 80–100 nm is distinct
from the non-altered area; this zone is defined as the space-weathered rim. The space-weathered rim is characterized by
crystallographic misorientations and the disappearance of superstructure reflections of troilite in electron diffraction patterns.
The rim contains opened vesicles that are aligned along the c-plane of the sulfides, as well as numerous tiny vesicles. The Fe/S
ratio on the surface of the rim is higher than in non-altered regions, indicating selective sulfur loss from the surface. Iron whiskers
protrude from the space-weathered rim and consist of polycrystalline metallic iron. The sulfide rims and the iron whiskers areboth coated with vapor-deposited materials.
Discussions: The crystallographic modifications of the sulfides are probably produced by solar wind irradiation. The loss of
sulfur atoms may be caused by combined processes including selective sputtering of sulfur atoms during solar wind implantation,
chemical reaction with solar wind hydrogen, and thermal effects produced by micrometeorite bombardments. The whiskers may
have been formed by continued sulfur loss and accumulation of excess iron atoms that lead to the growth of metallic nuclei on
the sulfide surfaces. Thermal stress induced by thermal cycling could also have contributed to the whisker growth.
The sulfur loss by the space weathering of iron sulfides may contribute to sulfur depletion detected on the surface of S-type
asteroid Eros [9]. Furthermore, the sulfur loss from iron sulfides likely causes mass-dependent fractionation of sulfur in regolithgrains and supports the notion that the enrichment of heavy sulfur isotopes in mature lunar soils is due to sulfur loss by space
weathering [e.g., 10]. Thus, iron sulfides are highly susceptible to decomposition by space weathering, which may change thechemical properties of regolith. The general similarities of space weathering of iron sulfides between the Moon and Itokawa
indicate that the alteration of iron sulfides is common among airless bodies in the solar system.

Fig.1 . Secondary electron images of whiskers on iron sulfide surfaces. (a) Iron sulfide grain on an Itokawa particle. Numerous
whiskers appear on the sulfide. (b) Enlarged image of an iron whisker on a sulfide surface of an Itokawa particle.
References:[1] Pieters C. and Noble S. K. 2016. J. Geophys. Res. Planet 121, 1865-1884. [2] Matsumoto T. et al. 2016. Geochim. Cosmochim.
Acta 187, 195-217. [3] Keller L. P. and McKay D. S. 1993 Science 261, 1305-1307. [4] Noguchi T. et al. Science 333, 11211125. [5] Matsumoto T. et al. 2020. Nat. Commun. 11, 1-8. [6] Matsumoto T. et al. 2021. Geochim. Cosmochim. Acta 299, 6984. [7] Tsuchiyama A. et al. 2011 Science 333, 1125-1128. [8] Papike J. et al. 1991. Lunar Source book, p121-181. [9] Trombka
J. I. et al. 2000, Science 289, 2101-2105. [10] Clayton R. N. 1974. Proc. Lunar Sci. Conf. 5th vol.2, pp. 1801-1809.

Extraterrestrial Non-Protein Amino Acids Identified in Carbon-Rich Particles Returned from
Asteroid Itokawa
Eric T. Parker1, Queenie H.S. Chan2,3 Daniel P. Glavin1 and Jason P. Dworkin1
1
NASA Goddard Space Flight Center, Greenbelt, MD 20771, U. S. A.
2Royal Holloway University of London, Egham, Surrey TW20 0EX, U.K.
3
The Open University, Walton Hall, Milton Keynes MK7 6AA, U.K.

In this work, amino acid analyses of the acid hydrolyzed hot water extracts of gold foils containing five Category 3 (i.e.,
carbon-rich) [1-4] particles returned by the JAXA Hayabusa mission were performed by liquid chromatography withfluorescence detection and time-of-flight mass spectrometry (LC-FD/ToF-MS). In advance of LC-FD/ToF-MS analysis, andafter hot water extraction and acid hydrolysis, samples underwent pre-column derivatization using o-phthaldialdehyde/Nacetyl-L-cysteine (OPA/NAC), which is a fluorescent tagging agent that facilitates chromatographic separation of chiralprimary amines. Initial analyses of these particles by JAXA using field emission scanning electron microscopy with energy
dispersion X-ray spectrometry suggested the particles possessed significant amounts of carbon. Prior to amino acid analysis,
infrared and Raman microspectroscopy analyses revealed highly primitive organic carbon was present in some grains [5].
Some terrestrial contamination, primarily as L-protein amino acids, was observed in all sample extracts. However, several
terrestrially uncommon non-protein amino acids were also identified. Some particle extracts were characterized by racemic(D ≈ L) mixtures of the non-protein amino acids β-amino-n-butyric acid (β-ABA) and β-aminoisobutyric acid (β-AIB) at low
abundances ranging from 0.09 to 0.31 nmol g-1. A larger abundance of β-alanine (9.2 nmol g-1, ≈4.5 times greater thanbackground levels), also a non-protein amino acid, were measured in a combined extraction of three particles. This β-alanine
abundance in these Hayabusa particles was ≈6 times higher than that (1.49 nmol g-1) measured in an extract of a grain of theCM2 Murchison meteorite, which was processed in parallel. The comparatively high abundance of β-alanine in these three
Hayabusa grains is surprising because Itokawa possesses similar features to that of amino acid poor LL ordinary chondrites,suggesting that perhaps the amino acid content observed in this study may be a result of exogenous delivery, as has beenreported in the analyses of other Hayabusa particles [1,6]. Elevated abundances of β-alanine and racemic β-AIB and β-ABA in
Hayabusa particles suggest these non-protein amino acids are not of terrestrial origin. These Itokawa results represent the firstpresentation of amino acids not of terrestrial origin in the extracts of material collected by an asteroid sample-return mission.
Furthermore, these results demonstrate the analytical capabilities of the protocols used in this work as viable options withwhich to explore the soluble organic chemistry of asteroids Ryugu and Bennu returned by the Hayabusa2 and OSIRIS-REx
missions, respectively.
References[1] Chan Q. H. S. et al. 2021. Scientific Reports 11. [2] Ito M. et al. 2014. Earth, Planets and Space 66. [3] Yabuta H. et al.
2014. Earth, Planets and Space 66. [4] Kitajima F. et al. 2015. Earth, Planets and Space 67. [5] Chan Q. H. S. et al. 2019.
Abstract #6223. 82nd MetSoc. [6] Burgess, K.D. and Stroud, R.M. 2021. Communications Earth & Environment 2.

NaCl in an Itokawa Particle: Terrestrial or Asteroidal?
Shaofan Che1 and Thomas J. Zega1,2
Lunar and Planetary Laboratory, University of Arizona, Tucson AZ
2
Department of Materials Science and Engineering, University of Arizona, Tucson AZ
1Introduction. The detailed mineralogies and compositions of the particles returned from asteroid Itokawa collected by the
Hayabusa mission were extensively studied over the past decade [e.g., 1-3]. However, the full range of nanoscale features ofthese returned samples are still not well understood. We previously reported NaCl grains in a focused-ion-beam (FIB) section
extracted from particle RA-QD-02-0248 [4]. In this study, these NaCl grains are re-examined to better understand their origins
and potential implications for the alteration processes on Itokawa.
Methods. The characterization work was conducted on the 200 keV Hitachi HF5000 scanning transmission electron
microscope (S/TEM) located at the Kuiper Materials Imaging and Characterization Facility, Lunar and Planetary Laboratory,
University of Arizona (Tucson, AZ, U.S.A.). The HF5000 is equipped a cold-field emission gun, third-order sphericalaberration corrector for STEM mode, and an Oxford Instruments X‐Max N 100 TLE energy-dispersive X-ray spectroscopy(EDS) system with dual 100 mm2 windowless silicon‐drift detectors providing a solid angle (:) of 2.0 sr.
Results. A total of five FIB sections were lifted out from RA-QD-02-0248 during the initial examination in August and
September 2016. [4] reported that Section #3 is composed of plagioclase and olivine with abundant NaCl grains, most ofwhich were randomly distributed on the plagioclase surfaces while some appeared be within the thickness of the section. The
NaCl grains were reported to vary in size from <20 nm to 200 nm and some of the large grains appeared euhedral, with cubic
or elongate shapes. No NaCl grains were found on the adjacent olivine. The plagioclase was also reported to contain thin (<15nm) K-feldspar lamella along its interface with olivine. We recently re-visited this FIB section to evaluate if the NaCl grains
were modified. Our STEM results show that the overall distribution of the grains did not change (Fig. 1). To better compare
the NaCl grains analyzed in 2016 and now, we overlaid the secondary electron (SE) images with each other (Fig. 2). The datasuggest that some grains grew larger and more euhedral and some adjacent grains merged into larger ones. We also reexamined the Section #4 containing plagioclase and olivine. STEM analysis shows abundant high-Z grains (~30 nm in size)
and many of them are on the surface of the FIB section. The EDS elemental mapping of these grains shows a clearly resolved
Cl K peak in a summed spectrum. Similar to Section #3, NaCl grains do not occur within the olivine in this Section #4.
Discussion. Halite crystals were previously reported in two ordinary chondrites, Monahans (H5) and Zag (H3-6) [5-6]. Several
lines of evidence, such as the widespread distribution of halite in the matrices and the ancient ages derived from the radiogenic
isotope dating methods, suggest a pre-terrestrial origin of halite in these meteorites. Micrometer-sized halite is also aubiquitous phase on the external surfaces of many Itokawa particles [7], and a recent TEM study of two Itokawa particles [8]showed that submicrometer-sized NaCl grains were present on the top surface of plagioclase below the capping layer. Theseauthors also described an outer NaCl rim surrounding plagioclase. Contrary to the halite grains in Monahans and Zag, those in
Itokawa particles do not show strong textural or compositional evidence for a pre-terrestrial origin, partly due to their small
sizes and extremely reactive nature [7]. Textural modifications of halite in the N2-ﬁlled storage box were previously observed[7].
The NaCl grains in the Itokawa sample RA-QD-02-0248 that we report on here could be contaminants introduced during theultramicrotomy or FIB sectioning. However, this scenario has difficulty in explaining why NaCl grains only occur on theplagioclase, instead of randomly dispersed in both plagioclase and olivine. Alternatively, NaCl grains might have formed
during the TEM analysis. Na in plagioclase could be mobilized by the high-voltage electron beam providing a potential Na
source for NaCl grains. However, this scenario has trouble explaining the source of Cl. The coarsening and change of shapesof NaCl grains could be driven by Ostwald ripening due to the relative low humidity in the N2-ﬁlled desiccator. Nonetheless,the lack of changes in the distribution and amount of NaCl grains after 5-year storage in the desiccator proves that significant
alteration did not occur during sample preservation.
If the NaCl grains in our FIB sections are native to the asteroid, which the TEM data supports, then such grains could haveformed through in situ alteration of plagioclase on Itokawa. Previous studies of phosphates and plagioclase in ordinarychondrites suggest that the initial fluid altering primary merrillite and anorthite was a hydrous brine containing Na, K, Cl and F,
and at the waning stage of alteration, the fluid could have become very dry and halogen-rich [9-11]. The saturation of NaCl in
the dry fluid could have subsequently resulted in the precipitation of halite [11,12].
Conclusion and further work. Our TEM investigation of Itokawa particle RA-QD-02-0248 suggests that the NaCl grains
might be native to Itokawa. We plan to conduct atomic-scale imaging with EDS to further investigate the structure andchemical composition of the NaCl grains in Section #3. We will also search for NaCl in another FIB section #5 that contains
twinned plagioclase.

Figure 1. TEM images showing the distribution of NaCl grains on the side surface of plagioclase. The images were obtained on
September 10th, 2021.

Figure 2. The SE image taken in September 2021 (left) is compared with that taken in September 2015 (right). The NaClgrains have been well preserved, except some of them show changes in size and shape.
References[1] Nakamura T. et al. 2011. Science 333:6046. [2] Thompson M. S. et al. 2014. Earth, Planets and Space 66:1. [3] Matsumoto
T. 2020. Nature communications 11:1. [4] Zega T. J. et al. 2017. Abstract #3037. 48th LPSC. [5] Zolensky M. E. et al. 1999.
Science 285:5432. [6] Rubin A. E. et al. 2002. Meteoritics & Planetary Science 37:1. [7] Noguchi T. et al. 2014. Meteoritics &Planetary Science 49:7. [8] Keller L. P. and Berger E. L. 2017. The Eighth Symposium on Polar Science/Ordinary sessions. [9]Jones R. H. et al. 2014. Geochimica et Cosmochimica Acta 132. [10] Lewis J. A. and Jones R. H. 2016. Meteoritics &Planetary Science 51:10. [11] Jones R. H. et al. 2016. American Mineralogist 101:11. [12] Zolotov M. Y. et al. 2005. Abstract#2271. 36th LPSC.

Northwest Africa 5401 CV chondrite: Not oxidized, not reduced, maybe in between?

1

T.J. Fagan1, M. Komatsu2, Y. Imai1 and N. Sumiwaka1
Dept. Earth Sciences, Waseda University, Tokyo, Japan
2
SOKENDAI, Kanagawa, Japan

Introduction: Variations in oxidizing vs. reducing conditions in the early solar system are recorded by the CV chondrites.
Nickel-poor compositions of troilite and relatively abundant Fe,Ni-rich metal are indicators of reducing conditions in a reduced
subgroup (CV3red), whereas Ni-rich sulfide and a paucity of Fe,Ni-rich metal grains are indicators of oxidizing conditions in
two oxidized subgroups (CV3oxA similar to Allende and CV3oxB similar to Bali) [1-3]. Raman analyses of temperaturesensitive carbon-rich matter have helped to show that the CV3red subgroup was metamorphosed at lower temperatures than theoxidized subgroups [2,4,5]. However, most CV chondrites appear to fall within one of the three subgroups—samples
representing intermediate metamorphic temperatures and red-ox conditions are rare.
In this project, we present petrologic data and Raman spectroscopy analyses to argue that the meteorite Northwest Africa
5401 (NWA 5401) represents an intermediate stage in metamorphic temperature and oxidation, between the CV3red andCV3oxA subgroups. The presence of an intermediate suggests that the CV3red and CV3oxA subgroups represent stages along
a continuum of temperature-oxidation conditions, and favors the interpretation that CV chondrites come from a single parent
body that experienced a range of metamorphic conditions (cf. [3]).
Samples and Methods: Two polished thin sections and several chips were prepared from a slab of NWA 5401. One of thethin sections contains a texturally distinct clast (similar to dark inclusions reported from other CV chondrites, e.g. [6]) within themain host lithology of NWA 5401. The other thin section includes a coarse-grained Ca-Al-rich inclusion (CAI). The thinsections were imaged using petrographic microscopes, a Hitachi S-3400N scanning electron microscope (SEM) and JEOL JXA
8900 electron probe microanalyzer (EPMA) at Waseda University. Quantitative elemental analyses of minerals were collectedby EPMA using a 15 kV, 20 nA, ~1-µm spot electron beam and well-characterized standards. Modes of chondrite components(chondrules, matrix, amoeboid olivine aggregates (AOAs), CAIs) were collecting by manually counting on a grid overlying
elemental maps of the two thin sections.
Raman spectra were collected at the Waseda Physical Properties Measurement Center using a laser excitation wavelengthof 532 nm and a spot size of ~3-4 µm focused by a 50x objective lens. The power at the sample surface was ~2.4 mW, theacquisition time was 10 seconds, and spectra were acquired in the range of 500-2200 cm-1. Spectral fitting was conducted usinga Lorentzian profile for the D-band, BWF profile for the G-band in the region of 900-1900 cm-1. Model spectra with poor fits
to data (R2 < 0.97) were excluded. The D- and G-bands (abbreviated for defect and graphite, respectively) are attributed tomolecular vibrations in carbon-rich matter; the full width at half maximum of the D-band (FWHM-D) decreases and peakintensity ratio of ID/IG increases with thermal maturity [4].
Results and Discussion: Large chondrules typical of CV chondrites are evident in the host lithology of NWA 5401 (Fig. 1).
The clast lithology has much smaller chondrules and a higher matrix/inclusions* ratio (*inclusions used here to represent highT components of chondrites including chondrules, CAIs and AOAs; see [7]). The NWA 5401 host has matrix/inclusions ~ 0.70.8, whereas the clast has matrix/inclusions ~ 3.8. Corresponding values determined by [7] are as follows: ~1.3 for Allende
and Tibooburra (CV3oxA); 0.8 and 1.2 for Bali and Mokoia, respectively (CV3oxB); 0.6 and 0.4 for Vigarano and Leoville,
respectively (CV3red, though Vigarano is a breccia with some CV3ox affinities). Bonal et al. (2020, ref. [2]) do not use thesame matrix/inclusions parameter, but do report matrix mode percentages, with averages (±1s) of 48.9 (±5.6) for CVoxA, 52.3(±8.5) for CVoxB and 35.1 (±7.2) for CVred. The matrix abundance of ~ 45 mode% of the NWA 5401 host lithology appears
typical for the oxidized CV subgroups, but somewhat high for CVred.
The extent of alteration in the coarse-grained CAI (labelled SC-9) in one thin section of NWA 5401 also appears
intermediate between observations reported from reduced and oxidized CV chondrites. Coarse-grained CAIs in Allende
typically have alkali-FeO-rich minerals near CAI rims and grossular-rich veins extending into CAI interiors [8], whereas coarsegrained CAIs from CVred lack the grossular-rich veins and have only minor abundances of alkali-rich secondary minerals near
CAI rims. In contrast, NWA 5401 CAI SC-9 has a widespread domain of alkali-rich minerals near its rim, but lacks thegrossular-rich veins typical of Allende CAIs.

Nickel concentrations in sulfides were among the first observations that led [9] to distinguish oxidized CVs (with highNi sulfides) from reduced CVs (with low Ni-sulfides); the variations in Ni abundances in sulfides are verified by [3] (Fig. 2).
Sulfides in NWA 5401 host lithology are near-endmember troilite with minimal Ni (Fig. 2).
Raman analyses show that the FWHM-D and ID/IG parameters of NWA 5401 fit most closely with previously compiled
analyses from the CVoxB subgroup, though there is some overlap with CVred (Fig. 3).
In summary, the NWA 5401 host lithology appears similar to the CVoxB and CVred groups in Raman parameters, to theCVred group in sulfide composition, but exhibits greater alteration in a coarse-grained CAI than is typical of CVred CAIs. The
matrix/inclusions ratio of NWA 5401 host is above that of most CVred chondrites and comparable to matrix/inclusions of someoxidized CVs. NWA 5401 may represent an intermediate metamorphic history between low-T metamorphism of CVred andhigher-T metamorphism typical of oxidized CVs.
References: [1] Weisberg et al. (2006) in Lauretta D.S. & McSween H.Y. (editors) MESS II, p. 19-52. [2] Bonal L. et al.
(2020) GCA 276: 363-383. [3] Gattacceca J. et al. (2020) EPSL 547: 116467 (9 pages). [4] Bonal L. et al. (2006) GCA 71:
1849-1863. [5] Bonal L. et al. (2016) GCA 189: 312-337. [6] Buchanan P.C. (1997) GCA 61: 1733-1743. [7] Ebel D.S. et al.
(2016) GCA 172: 322-356. [8] Fagan T.J. et al. (2007) MAPS 42: 1221-1240. [9] McSween H.Y. (1977) GCA 41: 1777-1790.

Fig. 1. Mg Ka map of NWA 5401 host and clast
lithologies. Arrows highlight boundary.

Fig. 3. Raman parameters collected in this study and reported by
Bonal et al. (2006; 2016; 2020).

Fig. 2. Nickel concentrations in sulfides in CV chondrites.
Ranges of values in the CV subgroups show averages fromindividual meteorites reported by Gattacceca et al. (2020)
and ranges of individual analyses collected for this study.

Organics and iron speciation in CI chondrites : a combined STXM and TEM study
Le Guillou C.1, Leroux H1 ., Bernard S.2, Viennet J-C.2, Marinova M.1 , Jacob D.1 , De La Pena F. 1, Brearley A.3 , El Kerni H.3
1
Unité Matériaux et transformation, Université de Lille, France
2
IMPMC-MNHN, Sorbonne Université, Paris, France
3
University of New Mexico, Albuquerque, USA
In order to precisely comparing the mineralogy and the nature organic matter of known chondrites with Ryugu samples, weinvestigated 6 FIB sections of Orgueil and 2 sections of Ivuna CI chondrites. Orgueil insoluble organic matter (IOM) was alsomeasured. We first performed Scanning Transmission X-ray Microscopy (STXM) at the Carbon and Iron edge, to determine
the speciation of these elements. We are performing Transmission Electron Microscopy (TEM), with a special focus on theelemental composition of phyllosilicates and organic matter.
STXM delivers hyperspectral dataset that can be processed pixel by pixel using the python hyperspy library[www.hyperspy.org/]. For the Iron L-edge, we fit the background and an arctangente and quantify the Fe3+/ ΣFe using
previously established calibration (Bourdelle et al., 2013, Le Guillou et al., 2015). For the Carbon K-edge, we fit thebackground, normalize to the carbon amount and then fit gaussians at given positions to quantify some of the functional groups
using previously established calibration (Le Guillou et al., 2018). Thanks to these procedures, we obtain quantitative maps andare able to describe the variablility and distribution at the scale of 10s of nanometer.
In Orgueil, Iron in phyllosilicates is oxidized, the Fe3+/Σfe varies between 65 and 80 %, with a dichotomy likely related to thefine grained/coarse-grained mixture of smectite and serpentine. Sulfides and oxides are also present.
Organics display three families of spectra (in addition to carbonates) :- Organic particles, which are aromatic-rich and show important variability from one particle to the next. They contain someketone and/or phenol groups. They are more aromatic than the IOM.
- diffuse organic, with is present all over the section, mixed at a fine scale with phyllosilicates. It is aliphatic and carboxylic
rich. The carbon amount is lower than in particles. They are less aromatic than the IOM.
- Carboxylic-rich particles, preseent localy in some section, they show a carboxylic peak higher than the diffuse OM, and isoften accompanied by a hydroxyl and/or a carbonate peak.

Figure 1. Maps based on liear combination fitting of individual components. On top, map based on the iron L-edge, showing different
regions with both slight redox variation but also iron content variation. Below, map based on the carbon speciation showing indiviaulaorganic particles (blue) embedded in diffuse OM (orange) covering the entire section.

In order to describe the variability, we plotted histograms (Fig. 2).
The iron valency is heterogeneous from section to section, possibly depending on the ratio of coarse/fine grained
phyllosilciates that are sampled each time. However, it could also be due to a more global variability of the sample at the
micrometer scale. Several areas need therefore to be investigated to fully describe them.
Diffuse OM is very heterogeneous at the FIB section scale, with a tail extending toward aromatic particles. The latter are notreally visible on the histograms because they are less abundant. There is also a little variability of the peak distribution,
especially in one of the section (G2-2).

Figure 2. Histograms of quantified proxies at the carbon K-edge (left) and Iron L_edge (right). They allow to visualize the distribution of thecomposition within each FIB section, as well as the heterogeneity among different FIB sections.

Altogether, these data will help us understand the history of the CI parent body. Similar data obtained on Ryugu samples havebeen obtained and are presently being processed.

Shocked regolith in asteroid 25143 Itokawa surface
Josep M. Trigo-Rodríguez1, S. Tanbakouei1 and Mark Burchell2
Institute of Space Sciences (CSIC-.IEEC), Campus UAB, C/ Can Magrans s/n, 08193 Cerdanyola del Vallés (Barcelona),
Catalonia, Spain,
2
Centre for Astrophysics and Planetary Science, University of Kent, Canterbury Kent CT2 7NR, Kent, United Kingdom,

1

A major milestone in space exploration was to achieve the first sample return from an asteroid by the Japanese Space Agency(JAXA) [1]. The detailed images of asteroid 25143 Itokawa transformed a faint point of light seen by telescope into an
intrincated rubble-pile asteroid, with a complexity that exemplifies the type of challenging bodies we need to confront assource of hazard to humans. These bodies surrounding our planet exhibit challenging properties because they have been
exposed over the eons to space weathering processes and numerous impacts. As a consequence, their crumbly surfaces arecovered by small particles, pebbles, and boulders [1]. The Japanese JAXA/ISAS Hayabusa mission collected micron-sizedparticles from the regolith of asteroid 25143 Itokawa [2]. We have studied some regolith grains using different analyticaltechniques in our Meteorite and Sample Return Clean Lab at the CSIC Institute of Space Sciences in Barcelona in order tounveil some of the processes in which they were formed [3].
There is an important debate about the dominant physical processes at work in the surface of these bodies. Certainly Near
Earth Asteroids (NEAs) are exposed to short-perihelion approaches that produce significant thermal stress changes in the rockforming minerals present in their surfaces. Nowadays, it is usually considered that most small regolith particles are producedby thermal fatigue [4], but obviously impacts should play an important role over longer time scales. Fine-grained regolith
could be useful to apply future In Situ Resource Utilization (ISRU) tests in NEAs, so there is specific interest in deciphering
the most dominant mechanisms. Then, which of these two mechanisms dominates the production of regolith over a body like
Itokawa?. This can be tested in a non-destructive way, just by studying the silicate phases using Raman spectroscopy. Itokawa
asteroid is a nice example of a rubble pile and its surface consists of heterogeneously distributed boulders, large rocks andpebbles: In addition, some regions contain fine-grained regolith made of pounded stones and small grits (Saito et al, 2006). A
particularly useful mineral to infer the existence of shock is olivine, as pointed out by Harriss and Burchell [5].
We have studied 3 Itokawa particles provided by JAXA with numbers S14, S23 and S47 were investigated (Table 1). The
polished upper sides of the three particles are shown in Figure 1. To study their specific mineralogy the samples were analyzed
by SEM/EDX (Quanta 650 FEG equipped with EDX Inca 250 SSD XMax20 detector). To identify possible shocked minerals
several regions of interest (ROIs) were defined. Then we have performed Micro-Raman spectra using a spot size of about 1 µm
and a laser power of 0.6 mW cm-2. We studied carrefully the chemical and mineralogical structure to get some clues on theirshock history. Raman spectra were taken at room temperature using the 5145 Å line of an Argon-ion laser with a Jobin-Yvon
T-64000 Raman spectrometer attached to an Olympus microscope, and using a CCD detector cooled by liquid nitrogen. We
concentrated in the silicate phases, so we decided to acquire the spectra in a working window between 100 and 1400 cm-1.
From the EDX images and the peaks found in the Raman spectra we are able to distinguish the major rock-forming minerals(Fig. 1).

Table 1.

Catalog numbers, maximum size and composition of the studied regolith samples.

Sample#Size (µm)

Main mineral phases

RA-QD02-0014

131.2 ± 0.1

Olivine, low-Ca pyroxene, plagioclase

RA-QD02-0023

149.4 ± 0.1

Olivine, troilite

RA-QD02-0047

108.0 ± 0.1

Olivine, low-Ca and high-Ca pyroxeneAs the main results of the study of the selected ROIs, our Raman spectra of olivine, found for two out of three grains, show two drifted peaks
P1=820 cm-1 and P2=850 cm-1 which are considered characteristics of a shocked phase [6]. A Raman spectrum for S14 particle is shown in
Fig. 1. The precise peak location depends on the forsterite (Fo) and fayalite (Fa) content of the olivine [7,8]. A Raman spectrum for S14
particle is shown in Fig. 1. The precise peak location depends on the forsterite (Fo) and fayalite (Fa) content of the olivine [8-9]. In any case,
Harriss and Burchell suggested that shocked olivines above 65 GPa exhibit permanent shifts in the 820 and 850 cm-1 peaks in their Raman
spectra [5].

Figure 1.

Raman spectrum obtained for olivine in sampleRA-QD02-0014

In conclusion, the shock experienced by Itokawa’s regolith grains can be inferred from the deformation found in the lattice of the olivine
grains. Our Raman study of three particles seems to indicate that a significant fraction of these grains could have experienced collisional
processing. Obviously the number of studied grains so far is not statistically significant, but this finding could encourage other groups tocomplete a more comprehensive study. If these preliminary results are correct, a significant fraction of the regolith particles collected in theMuses Sea were shocked, and fragmented by impact excavation more than by thermal fatigue. In fact, such scenario is likely because nanoindentation studies we performed on these grains [1] seem to point that the minerals exhibit similar mechanical properties than ordinarychondrites of similar composition [3].
Acknowledgements
JMTR and ST acknowledge financial support from research project PGC2018-097374-B-I00, funded by FEDER/Ministerio de Ciencia eInnovación – Agencia Estatal de Investigación (PI: JMTR).

References[1] Nakamura T., et al., 2012. Science 333, 1113. [2] Saito, J., et al. 2006. Science, 312, 1341. [3] Tanbakouei, S., et al., 2019.
Astronomy & Astrophysics, 629, p.A119. [4] Delbo M. et al. 2014. Nature, Volume 508, 233. [5] Harriss, K.H., and Burchell,
M.J., 2016. Meteoritics & Planetary Science 51, 1289. [6] Mohanan, K., et al. 1993. American Mineralogist, 78,.42. [7]Chopelas, A., 1991. American Mineralogist, 76, 1101. [8] Kuebler K. E., et al. 2006, Geochim. Cosmochim. Acta, 70, 6201.[9]Foster N.F., et al. 2013. Cosmochimica et Geochimica Acta 121, 1.

Organic matter in Itokawa particles
Q. H. S. Chan1,2, A. Stephant2, I. A. Franchi2, X. Zhao2, R. Brunetto3, Y. Kebukawa4, T. Noguchi5, D. Johnson2,6, M. C. Price7,
K. H. Harriss7, M. E. Zolensky8, M. M. Grady2,9, E. T. Parker10, D. P. Glavin10, and J. P. Dworkin10
1
Royal Holloway University of London, Egham TW20 0EX, Surrey, UK. 2The Open University, Walton Hall, Milton Keynes
MK7 6AA, UK. 3IAS-Université Paris-Saclay, 91405 Orsay, France. 4Yokohama National University, Yokohama 240‑8501,
Japan. 5Kyushu University 744, Motooka, Nishi‑ku, Fukuoka 819‑0395, Japan. 6University of Exeter, Penryn, Cornwall TR10
9FE, UK. University of Kent, Canterbury CT2 7NH, Kent, UK. 8NASA Johnson Space Center, Houston, TX 77058, USA. 9The
Natural History Museum, London SW7 5BD, UK. 10NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.
The first Hayabusa mission returned samples from the near-Earth S-type asteroid 25143 Itokawa to Earth in 2010 [1].
Although Itokawa has a lithology related to ordinary chondrites (OCs) that typically have low organic contents, several
Itokawa particles were found to contain organic matter (OM) [2-5]. However, there was not an explicit conclusion to the originof the observed OM in these early studies. We have extended our search for OM into other Itokawa grains. Here, we report
extraterrestrial OM (macromolecular carbon and amino acids) observed in six Itokawa particles (including a category 1
particle: RA-QD02-0162 [#62; also nicknamed “Amazon”], and five category 3 carbon-rich particles: RA-QD02-0012 [#12],
RA-QD02-0078 [#78], RB-CV-0029 [#29], RB-CV-0080 [#80] and RB-QD04-0052 [#52]).
All allocated Itokawa samples were initially analysed by spot and point-by-point mapping Raman spectroscopic
analysis at the Open University, UK. Amazon was then transferred and mounted into indium on an aluminium stub, which wasstudied with a NanoSIMS 50L ion microprobe for its H,C,N isotopic compositions. The rest of the samples were mounted insterile gold foils, and the amino acid contents of their acid hydrolysed hot water extracts were obtained with a liquid
chromatography with tandem fluorescence and accurate mass detection at NASA Goddard Space Flight Center, USA.
Based on the observation of the Raman parameters (e.g. the peak locations and widths of the defect (D) and graphite(G) bands) [6], a significant variety of carbonaceous materials has been observed in Amazon. The carbonaceous materials
include primitive and unaltered OM that shares similarity with the IOM in primitive (CI,CM,CR) carbonaceous chondrites, aswell as OM that has been heavily graphitised. The organic structure of the heated material is best represented bynanocrystalline graphite, comparable to that observed for metamorphosed meteorites (e.g., L3–6 Inman, Tieschitz and New
Concord, CV3 Allende, and EH4 Indarch), suggesting peak metamorphic temperatures (PMT) of >~600°C. The thermal
history recorded in the graphitic OM agrees with PMT estimates for returned Itokawa regolith grains (600–800°C) [7].
We have obtained the H,C,N isotopic compositions for the primitive OM in Amazon, which exhibits unambiguously
extraterrestrial isotopic signatures (δD = +4868 ± 2288‰; δ13C = −24 ± 5‰; δ15N = +344 ± 20‰), contrasting to the typicallynegative isotopic values obtained for terrestrial organic matter [8]. The δD and δ13C values of the organic material in Amazon
are comparable to OCs, however, the δ15N value is higher than that typically observed for OCs (δ15N = −47 to +36‰), and issimilar to that of CRs (δ15N = +153 to +309‰) [9]. Our data suggest a genetic link between the primitive organic material
observed in Itokawa to CRs and IDPs for they share similar D, 13C and 15N enrichments [10].
The high carbon contents of the five category 3 Itokawa particles suggest potentially higher OM abundances, hence
we extracted and analysed amino acids in these samples. Although terrestrial contamination was observed primarily as Lprotein amino acids, several terrestrially uncommon non-protein amino acids were also observed at low abundances, such as βaminoisobutyric acid (β-AIB), β-amino-n-butyric acid (β-ABA), and β-alanine. Itokawa amino acid content observed here wasdissimilar to thermally altered OCs, but preliminarily analogous to more aqueously altered CR2s.
Continued evolution of Itokawa is evident by the infall of primitive organic material derived from CRs/IDPs,
accounting for a complex interplay between the remnant Itokawa silicates with exogenous organics. The results reported here
are the first evidence of extraterrestrial OM in asteroid material from a sample-return mission, showcasing a working protocol
for analysing samples returned by the Hayabusa2 and OSIRIS-REx missions.
References[1] Yada, T., et al. Meteoritics & Planetary Science, 2014. 49(2): p. 135-153. [2] Ito, M., et al. Earth, Planets and Space, 2014.
66(1): p. 91. [3] Yabuta, H., et al. Earth, Planets and Space, 2014. 66(1): p. 1-8. [4] Uesugi, M., et al. Earth, Planets and Space,2014. 66(1): p. 1-11. [5] Kitajima, F., et al. Earth, Planets and Space, 2015. 67(1): p. 1-12. [6] Tuinstra, F. and J.L. Koenig.
Journal of Chemical Physics, 1970. 53(3): p. 1126-1130. [7] Nakamura, T., et al. Science, 2011. 333(6046): p. 1113-1116. [8]Pizzarello, S. Accounts of Chemical Research, 2006. 39: p. 231-237. [9] Alexander, C.M.O.D., et al. Geochimica et
Cosmochimica Acta, 2007. 71: p. 4380-4403. [10] Busemann, H., et al. Science, 2006. 312: p. 727-730.

Hayabusa2 curation: from concept, design, development, to operations
Masanao Abe1,2, Tomohiro Usui1, Shogo Tachibana1,3, Tatsuaki Okada1,3, Shino Suzuki1, Haruna Sugahara1, Toru Yada1,
Masahiro Nishimura1, Kanako Sakamoto1, Kasumi Yogata1, Akiko Miyazaki1, Aiko Nakato1, Kana Nagashima1, Rei
Kanemaru1, Kentaro Hatakeda1,4, Kazuya Kumagai1,4, Yuya Hitomi1,4, Hiromichi Soejima1,4, Miwa Yoshitake1,X, Ayako
Iwamae1,4,Y, Shizuho Furuya1,3, Tasuku Hayashi1, Daiki Yamamoto1, Ryota Fukai1, Takuya Ishizaki1, Hisayoshi Yurimoto5
1
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara 252-5210, Japan,
2
The Graduate University for Advanced Studies (SOKENDAI), Hayama 240-0193, Japan,3University of Tokyo, Bunkyo, Tokyo
113-0033, Japan, 4 Marine Works Japan, Ltd., Yokosuka 237-0063, Japan,5Hokkaido University, Sapporo 060-0810, Japan

Introduction: JAXA conducted and is conducting sample return missions, such as Hayabusa and Hayabusa2, to bring backsamples of extraterrestrial materials from asteroids (S-type asteroid Itokawa and C-type asteroid Ryugu, respectively). The
returned materials are scientific valuable samples that can provide scientific knowledge about the origin and evolution of the
Solar System [1]. Prior to sample return, meteorites were the only accessible extraterrestrial samples to unravel the history of
the Solar System. However, meteorites have to be strong enough to fly through the Earth's atmosphere to fall, and, after
dropped on the ground, they are contaminated by terrestrial atmosphere, water and materials, changing their properties. On theother hand, sample return missions allow to store the sample in a sealed container and protect them from terrestrial
contamination and from heat and shock during re-entry to the Earth. Returned samples are very valuable scientifically, and it isextremely important to handle them without compromising their scientific characteristics.
Scientific requirement: The curation center that handles returned samples has the following scientific requirements tomaintain the high scientific value of the returned samples: 1) Do not expose the sample to the Earth's atmosphere; 2) Do not
lose the sample; 3) Do not destroy the sample except for when needed. The first requirement is to prevent the samples frombeing reacted with terrestrial materials to be altered. If the terrestrial compounds are mixed into the sample, the reliability of
the analytical results is not ensured. The second requirement should of course be met considering the cost, time, and humanresources to get samples back from space. The third requirement is not strict, but refers only to preliminary examination of thesamples. The preliminary examination team at the curation center performs first description of the returned samples before
detailed initial analysis by the project-lead analysis team. The destructive analysis of the sample should not be performed in the
preliminary examination at the curation center in order to enable the initial analysis team to perform a comprehensive analysis
that combines the morphological observation of the sample and the destructive chemical analysis.
Role: The curation center is responsible for the receipt and preliminary analysis (we call it “initial description”) of returned
samples while satisfying the above requirements as well as the long-term storage and scientific investigation of the samples
after the initial description. Examples of the initial description include size and shape description by optical observation,
sample mass measurements, non-destructive spectroscopic observations for chemical and mineralogical analysis. In the case of
Hayabusa, the total amount of sample brought back from Itokawa was small (i.e., about 1 mg) and spectroscopic observation
was difficult. To compare with the data of the X-ray fluorescence spectrometer on-board the Hayabusa spacecraft, elemental
analysis was also carried out by SEM/EDS during the initial description stage [2]. All these preliminary analyses have theimportant role to provide a scientific link between the sample brought back and the target body. Normally, the returned
samples are stored in a special storage container, and it is necessary to take out the sample from the container by a special
procedure. After the initial description, except for a part of the sample stored separately for future use, around half of samples
is distributed for detailed analysis, for example the initial analysis and the AO (Announcement of Opportunity) research, which
is open to the science community. The sample distribution also requires curational work, such as taking out and storing thesamples in a distribution/transport container and tracking the analysis records.
Design: In consideration of the above roles, JAXA has designed clean rooms and clean chamber dedicated to each sample
return mission (Hayabusa and Hayabusa2). The primary reason for this is to avoid mixing of samples from different targets but
it is also because the method of taking out the samples from the container and the planned analyses for the initial description
were different for the two missions. The facility design for the curation center initiated about 5 years before the sample
returned to Earth. This is because it was expected to need one year for designing, two years for manufacturing, one year for
confirming functions after manufacturing, and one year for rehearsal of the operation for receiving the returned sample. At thedesign stage, the specification study team from the JAXA curation members, the design team of the spacecraft sampler, andsample scientists from the research community played a central role in establishing the required specifications. After that, themanufacturer was selected by bidding after receiving the specification approval from the curation steering committee and the
Hayabusa/Hayabusa2 project team.
Specifications for Clean room: The specifications of the clean room at the JAXA Curation Center are basically the same for
Hayabusa and Hayabusa2. The cleanliness of the clean room where the clean chamber is installed is Class 1000 (US federal
standard), equivalent to Class 6 in ISO 14644-1 standard. The floor has a grating structure, and the return airflow travels fromthe bottom of the grating through the back of the wall to the ceiling and circulates from the ceiling using a ULPA filter toremove dust in the air. The clean room is maintained at a pressure higher than the outside to prevent outside contamination.
The positive pressure control is performed with the adjacent downstream room, and the shortage is taken in from the outside
air through a filter by approximately 10% of the circulating air volume. Temperature and humidity are controlled andmaintained at 24±2 °C and at 50±10% RH, respectively. The humidity is maintained at a high value to suppress the generationof static electricity. The supply pipes for exhaust gas, purified gas, cooling water, compressed air, etc. are connected to theclean chamber through a grating floor. Equipment that degrades the environments (for example, rough grinding pumps) areinstalled in isolated areas outside the clean room.
Specifications for Clean chamber: The clean chamber of the JAXA curation center is designed to perform all theoperations on samples in a vacuum or pure nitrogen gas environment, i.e., sample extraction from the sample storage container,
initial description of the samples, and distribution and storage of the samples. In particular, because the structure of the sample
storage container of Hayabusa and Hayabusa2 is complex to store and deliver the samples safely, the clean chambers for bothmissions are required to have the interface to the sample container opening mechanism. Electrolytic polishing was applied tothe inner surface of the chambers for quick cleaning recovery and to avoid contamination to the samples as much as possible.
Several types of clean chambers are prepared for the purpose of work after opening the sample storage container, and they areconnected to each other through gate valves. In principle, the sample container opening work is performed in a vacuum
environment, but the sample removal, initial description, and distribution work have been performed through gloves in a highpurity nitrogen environment. Viton gloves were initially used to minimize organic contamination, but due to the difficulty inobtaining them because of the discontinuation of production, mainly Viton coated butyl gloves have recently been used.
Materials used for the jigs used in the clean chamber and materials of the chamber itself were chosen to avoid materials otherthan those used in the sampling device of the spacecraft as much as possible in order to control the contamination. In particular,
the containers to store the samples are basically made of synthetic quartz glass or sapphire, and in some cases stainless steel,aluminum, or Teflon are permitted to use. The use of copper- or gold- plated sample holders for certain analyses such as
SEM/EDS is also allowed.
Operations and development: The curation center has been operated by the Astromaterials Science Research Group(ASRG) of ISAS, which is responsible for curational work (receipt, description, utilization, and storage) on extraterrastrial
returned samples and for facility maintenance [3]. Hayabusa 2 samples were returned in December 2020. After opening thesample storage container in a vacuum environment, most of the curation work has been performed by using gloves in anitrogen environment. The Hayabusa2 science team required the ASRG to pick up a small fraction of samples to store in a
vacuum environment for future analytical studies without ever being exposed to nitrogen gas. Therefore, at the JAXA Curation
Center, the clean chamber of Hayabusa2 has the new function of observing the inside of the sample storage container andtaking out a part of the sample in a vacuum environment. Two millimeter-sized particles were successfully picked up and are
now stored in the vacuum environment.
A total of 5.4 g of Ryugu samples were collected from the chambers A and C of the sample container, which were used forthe sample collection at the first and second touchdown sites. The maximum particle size of the sample is about 1 cm, andhundreds of samples with a particle size of 1 mm or more have been confirmed. In the curation center, we plan to store eachparticle in an individual container as much as possible, acquire initial description data for individual particles to list in thesample catalog. The ASRG has independently-developed handling tools and sample containers to improve work efficiency
while minimizing contamination. We believe that these developments will also help us receive and curate future returned
samples. The ASRG also study Ryugu samples along with the project-lead initial analysis, which will also provide new
insights into the origin and evolution of the Solar System.
References[1] Tachibana S. et al. 2014. Geochem J 48:571. [2] Yada T. et al. 2014. Meteoritics & Planetary Science 49:135. [3] Abe M.
2021. Sample Return Missions. The Last Frontier of Solar System Exploration (book), Chapter 12.

Sample Analysis Plan for NASA’s OSIRIS-REx Mission
H.C. Connolly Jr1,2, T.J. Zega2 V.E. Hamilton3, J.P. Dworkin4, K. Nakamura-Messenger5, C.W.V. Wolner2, C.A. Bennett2, P.
Haenecour2, and D.S. Lauretta2
1
Rowan University, Glassboro, NJ, USA (connollyh@rowan.edu)
2Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA
3Southwest Research Institute, Boulder, CO, USA
4
NASA Goddard Space Flight Center, Greenbelt, MD, USA
5
NASA Johnson Space Center, Houston, TX, USA
OSIRIS-REx [1,2] is the third mission in NASA’s New Frontiers program and its first asteroid sample return mission. In October
2020, the OSIRIS-REx spacecraft successfully performed its Touch-and-Go (TAG) maneuver to collect a sample of regolith [3]from the surface of its target, asteroid (101955) Bennu, and is now on its return cruise to Earth. On 24 September 2023, theSample Return Capsule (SRC) is scheduled to be released from the spacecraft and gently land in the desert of the western U.S.
state of Utah. After it is recovered, the SRC will be placed into an inert environment, safely packed, and flown to Houston, Texas,
where it will go directly to the new OSIRIS-REx curation facility located within NASA’s Johnson Space Center. Once within
the facility, the SRC will be opened, and the sample will be quickly (within hours to days) processed for distribution to the
OSIRIS-REx Sample Analysis Team (SAT) for immediate investigation. In addition, the Japan Aerospace Exploration Agency
will receive 0.5% of the unprocessed bulk material and the Canadian Space Administration will receive 4%. A catalog of theentire sample will be produced within six months and will enable requests of the remaining material by the scientific community.
The OSIRIS-REx Sample Analysis Plan (SAP) establishes a hypothesis-driven framework for integrated, coordinated analysesof the returned sample with the goal of satisfying the mission requirement to “return and analyze a sample of pristine
carbonaceous asteroid regolith in an amount sufficient to study the nature, history, and distribution of its constituent minerals
and organic material.” Through analysis of the returned sample, the SAT will test a total of 12 primary hypotheses, eachencompassing several secondary hypotheses. The primary hypotheses are:
1. Remote sensing of Bennu’s surface has accurately characterized its mineral, chemical, and physical properties.
2. Bennu contains prebiotic organic compounds.
3. Bennu contains presolar material derived from diverse sources.
4. Bennu’s parent asteroid formed beyond the snow line by accretion of material in the protoplanetary disk.
5. Geological activity occurred in the interior of Bennu’s parent asteroid early in solar system history.
6. Bennu’s parent body experienced > 3 billion years of solar system history before being destroyed in a catastrophic
disruption.
7. Bennu is a rubble pile that formed by re-accumulation of material from the catastrophic disruption of a precursor asteroid.
8. The Yarkovsky effect pushed Bennu far enough inward to reach a dynamical resonance, which flung it out of the main
belt and onto a terrestrial planet-crossing orbit.
9. Bennu has experienced surface processing throughout its history.
10. The physical, chemical, and spectral properties of Bennu’s surface materials have been modified by exposure to thespace environment.
11. The Hokioi Crater in which the Nightingale sample site is located was recently formed and contains relatively
unweathered material [4].
12. OSIRIS-REx asteroid proximity operations, the TAG event, and Earth return modified the collected samples, Touchand-Go Sample Acquisition Mechanism (TAGSAM), and the SRC.
Each hypothesis is mapped to one or more SAT working groups and analytical technique(s) needed to produce the data to test it.
The SAP applies a three-tiered approach to allocating sample mass for analyses. (i) The “baseline” analysis plan assumes that15 g of sample will be available to the SAT. This mass is based on the assumption of returning 60 g, the mission-required
minimum, and the fact that 75% of the sample (in this scenario, 45 g) will be archived for future community analysis. (ii) The“overguide” analysis plan assumes that 62.5 g of sample will be available to the SAT. This mass is based on the best-available
spacecraft-based estimate of the total mass of sample stowed, about 250 g [5]. (iii) The “threshold” analysis plan assumes that

3.75 g of sample will be available to the SAT. This mass addresses a contingency scenario in which an anomaly during Earthreturn results in a significant mass loss, such that only 15 g is recovered. The threshold plan’s other purpose is to guide analysisof any rare lithologies that might be returned as part of the bulk sample.
To test the effectiveness of our SAP and ensure that the SAT is prepared for the analysis of the returned sample, the mission willconduct a Sample Analysis Readiness Test (SART) from June 2022 to June 2023. The SART will focus on aspect of the SAP
for which verification or demonstration of proficiency is needed such as follow-on analyses, testing of new or updated equipment,
and implementation of new software discussed below. During the SART, the mission will implement a new data storage,
processing, sharing, and visualization system designed to enable coordinated analysis, called the Sample Analysis MicroInformation System (SAMIS). SAT members will test their proficiency with the two user-facing modules of SAMIS: the Sample
Analysis Tracking Application (SATA), which provides real-time tracking of the location and condition of sub-samples as they
are shipped between laboratories and the curation facility, and the Sample Analysis Desktop Application (SADA), which
provides a central point of upload, download, spatial co-registration, and visualization of analytical data. Finally, because alldata from the mission’s sample analysis phase will be archived, the SAT will use the SART to practice data archiving. Periodic
reviews of the SART will occur during its implementation, and lessons learned will be applied to the SAP, applications, andarchiving approach. A final report on the outcomes of the SART will be produced in the summer of 2023 (before the sample isreturned to Earth).
References[1] Lauretta, D.S. et al. 2017. Space Science Reviews 212:925. [2] Lauretta, D.S. et al. 2021. In Sample Return Missions,Longobardo, A., ed. (Elsevier), ch. 8. [3] Lauretta, D.S., & OSIRIS-REx TAG Team 2021. 52nd LPSC LII, Abstract# 2097. [4]Enos et al. 2020 Abstract #1463. 51st LPSC. [5] Ma, H. et al. (2021) arXiv:2109.05561 [astro-ph.EP].

Scientific importance of the sample analyses of Phobos regolith and the analytical protocols of
returned samples by the MMX mission
Wataru Fujiya1, Yoshihiro Furukawa2, Haruna Sugahara3, Mizuho Koike4, Ken-ichi Bajo5, Nancy L. Chabot6, Yayoi N. Miura7,
Frederic Moynier8, Sara S. Russell9, Shogo Tachibana10, Yoshinori Takano11, Tomohiro Usui3, and Michael E. Zolensky12
1
Ibaraki University, 2Tohoku University, 3Institute of Space and Astronautical Science, JAXA, 4Hiroshima University,
5
Hokkaido University, 6Johns Hopkins University Applied Physics Laboratory, 7Earthquake Research Institute, University ofTokyo, 8Institut de Physique du Globe de Paris, CNRS, 9Natural History Museum, 10UTOPS, University of Tokyo, 11Japan
Agency for Marine-Earth Science and Technology, 12NASA Johnson Space Center
The Martian Moons eXploration (MMX) mission by JAXA is a sample return mission from a Martian moon, Phobos, aiming
at collecting >10 g of the regolith materials on Phobos. The touchdown operations are planned to be performed twice at
different landing sites. The regolith materials will be collected using coring (C-) and pneumatic (P-) sampling systems [1]. We,
Sample Analysis Working Team (SAWT) members, are now designing the analytical protocols of returned Phobos samples [2].
The origin of the Martian moons is unclear, but there are currently two favored formation scenarios: (i) the in-situ formation(giant impact) scenario [e.g., 3], and (ii) the captured asteroid scenario [e.g., 4]. If Phobos formed by giant impact, then the
Phobos building blocks were likely heated to high temperatures (ca., ~2000 K), and the returned samples will consist of
igneous and/or glassy materials produced by the solidification of melt or the condensation of gas [5]. On the other hand, If
Phobos is a captured asteroid, then the returned samples would be primitive materials like carbonaceous chondrites as inferredfrom Phobos’ surface spectra resembling D-type asteroids [e.g., 6]. Observations of the returned samples under an optical
microscope, quantitative analysis of their chemical compositions, and isotope measurements of, e.g., O, Ti, and Cr, candistinguish between the above formation scenarios, and characterize the Phobos endogenous materials [e.g., 7].
In the case of the giant impact scenario, the volatile loss accompanied by the giant impact can be evaluated using the isotopic
compositions of moderately volatile elements like Zn [8]. Radiometric dating by, e.g., Pb-Pb and Rb-Sr systematics, will
provide chronological information about the giant impact event [9]. In the case of the captured asteroid scenario, analyses oforganic matter, bulk H and N isotopic compositions, and presolar grain abundance will provide insights into the primitivenessof the Phobos endogenous materials. The timing when the Martian gravity captured Phobos can be constrained by the
combination of Ar-Ar dating of the returned samples and the crater counting of the Phobos’ surface [10]. In either formation
scenario, the sample analyses mentioned above can shed light on the material transport in the solar system and the delivery ofvolatiles to the terrestrial planets.
It should be noted that the Phobos’ regolith may contain materials ejected from Mars by impact throughout the Martian history[11]. The Martian materials on Phobos may include fragile ones like sedimentary rock, which cannot be found in Martian
meteorites commonly shocked by >5 GPa [12]. These Martian materials will provide crucial information about the surface
evolution of Mars. Furthermore, biomarkers or even potential microorganisms could be detected in the Martian materials on
Phobos, although MMX has no concern about viable Phobos organisms to be returned [13]. We plan to design the analytical
protocols of the returned samples to detect such Martian materials in curation procedures before they are processed for further
analyses.
References[1] Usui T. et al. 2020. Space Sci. Rev. 216:49. [2] Fujiya W. et al. 2021. Earth Planets Space 73:120. [3] Hartmann W. K.
1990. Icarus 87:236–240. [4] Citron R. I. et al. 2015. Icarus 252:334-338. [5] Pignatale F. C. et al. 2018. Astrophys. J. 853:118(12pp). [6] Murchie S. & Erard S. 1996. Icarus 123:63-86. [7] Trinquier A. et al. 2007. Astrophys. J. 655:1179-1185. [8]Paniello R. C. et al. 2012. Nature 490:376-379. [9] Amsellem E. et al. 2020. Icarus 339:113593. [10] Schmedemann N. et al.
2014. Planet. Space Sci. 102:152-163. [11] Hyodo R. et al. (2019) Sci. Rep. 9:19833. [12] Fritz J. et al. 2005. Meteorit. Planet.
Sci. 40:1393-1411. [13] Hyodo R. & Usui T. 2020. Science 373:742.

What should we do with these Martian rocks? A tale of MSR Sample Science and Curation
Aurore Hutzler1, Gerhard Kminek1, Michael Meyer2, Lindsay E. Hays2 and Sanjay Vijendran1
1
European Space Agency, The Netherlands
2
NASA Headquarters, Washington, DC, USA
The Mars Sample Return (MSR) campaign is the most complex and ambitious sample return mission to date. The first leg ofthe campaign, Mars 2020, has successfully landed in the Jezero crater, and the rover Perseverance is already sampling Mars.
ESA and NASA have allocated substantial budgets to support the development of a partnership formalised through thesignature in October 2020 of a NASA-ESA Memorandum of Understanding (MOU) concerning the flight elements of the
MSR Campaign. A fundamental aspect of the partnership as stated in the Joint Statement of Intent between NASA and ESA on
MSR campaign science benefits signed on 2 July 2019, is that samples would be treated as one collection and jointly managed.
This has been a leading principle for all subsequent actions.
To clarify the activities to be done on the collection, the MSR Science Planning Group (MSPG) in 2018, followed by a second
MSPG2 in 2020 were jointly chartered by NASA and ESA to develop key technical inputs for the curation and science
activities to be done in the first years after sample return. These inputs have been translated into proposed design requirements
for the short- to medium-term needed infrastructure [1]. One of the MSPG2 working groups has delivered a framework for thescience management of the collection [2]. Final reports and requirements from MSPG2 were delivered in July 2021. In parallel,a Sample Safety Assessment Protocol working group under the umbrella of COSPAR is currently finishing their deliberations
and report [3]. This sample safety assessment overlaps with the time critical and sterilisation sensitive science identified by
MSPG2 for execution in the above referenced infrastructure. All these community-defined requirements, recommendations
and finding are going to feed into the next steps to prepare the ground-segment activities and infrastructure. As a minimum,
there is a need for a Sample Receiving Facility (SRF) for the first years after landing. This primary SRF should be jointlymanaged between ESA and NASA, and allow for all needed curation, sample handling and sample analysis (pre-Basic
Characterization, Basic-Characterization and Preliminary Examination as well as sterilization-sensitive, time-sensitive scienceand sample safety assessment) to be done in containment. NASA and ESA are planning independent but coordinated studies toclarify the design trade space and cost associated with handling Mars samples. A formalisation of the NASA/ESA partnershipfor MSR ground-segment is also underway, with an upcoming Science MOU (2021) and a potential agreement on groundinfrastructure (planned 2022).
The upcoming decade will be busy with preparing the infrastructure, the science, and the overall management of the samples.
There will be ample opportunities for the worldwide community to participate in the preparation activities, with a joint
ESA/NASA Announcement of Opportunity expected soon, followed by more AOs later in the 2020’s.
References[1] Carrier B.L. et al. 2021, Astrobiology [2] Haltigin T. et al. 2021, Astrobiology [3] Kminek G et al. 2021, SSAP

A New Laboratory Facility in the Era of Sample Return: the Sample Analysis Laboratory (SAL)at DLR Berlin
1

E. Bonato1, S. Schwinger2, A. Maturilli1, J. Helbert1
Dept. of Planetary Laboratories, Institute of Planetary Research, DLR, Rutherfordstraße 2, 12489, Berlin, Germany
2
Dept. of Planetary Physics, Institute of Planetary Research, DLR, Rutherfordstraße 2, 12489, Berlin, Germany

DLR is currently in the process of setting up a new Sample Analysis Laboratory (SAL) – a facility dedicated to the work onrock and dust samples returned from planetary bodies such as asteroids and the Moon. The key question driving thedevelopment of SAL is a more in depth understanding of the formation and evolution of planetary bodies.
SAL extends the currently available laboratory facilities at the Institute of Planetary Research at DLR in Berlin, including thePlanetary Spectroscopy Laboratory (PSL), the Raman Mineralogy and Biodetection Laboratory (RMBL). SAL is focused
primarily on in situ mineralogical and geochemical analysis mainly of extra-terrestrial material returned from sample return
missions, as well as of meteorites and sample analogue materials.
Housed within ISO5 clean rooms, SAL will be equipped with glove boxes for handling and preparation of the samples. All
samples will be stored under dry nitrogen and can be transported between the instruments in dry nitrogen filled containers.
The instrumentation in the first step of the SAL set up consists of:• Field Emission Gun Electron Microprobe Analyser (FEG-EMPA)• Field Emission Gun Scanning Electron Microscope (FEG-SEM)• X-ray Diffraction (XRD):•
high resolution qualitative and quantitative analyses of powders•
μ-XRD for in situ analysis and mapping•
Non-ambient stage for dynamic experiments• Vis-IR-microscope• Polarized light microscope with automated stage• supporting equipment for sample preparation and handling within a controlled atmospheric environment.
SAL is currently being set up. Construction work for the laboratories has started and the first instruments will be arriving bysummer 2022. SAL will be operational by the end of 2022, on time to welcome samples collected by the Hayabusa2 mission.
In collaboration with the Natural History Museum in Berlin will also have the expertise and facilities for carrying out
curation of sample return material which will be made available for the whole European scientific community. DLR is alreadycurating a 0.45 mg of Lunar regolith (Figure 1) collected from theLuna 24 Soviet mission and the first analyses of the material arebeing planned.
SAL follows the approach of a distributed European sample
analysis and curation facility as discussed in the preliminary
recommendation of EuroCares. Together with other laboratory
facilities at the DLR Institute of Planetary Research (such PSL
and RMBL) which are part of the Europlanet RI, the new SAL
will be from the start open to the scientific community.
Our goal is to establish an excellence center for sample analysis in
Berlin within the next 5-10 years building on our collaborations
with the Natural History Museum and the Helmholtz Center
Berlin in Berlin as well as the universities in Berlin.

Figure 1. Glass vial containing Lunar regolith collected during the Luna
24 mission.

Milani CubeSat for ESA Hera mission
Tomáš Kohout 1,2, Margherita Cardi3, Antti Näsilä4, Ernesto Palomba 5, Francesco Topputo6, and theMilani team*1
University of Helsinki, Faculty of Science, Helsinki University, Finland (tomas.kohout@helsinki.fi)
2
Institute of Geology of the Czech Academy of Sciences, Prague, Czech Republic3
Tyvak International, Torino, Italy
4
VTT Technical Research Centre of Finland, Espoo, Finland5
INAF-IAPS, Rome, Italy
6
Politecnico di Milano, Milano, Italy*
A full list of authors appears at the end of the abstract
Hera is the European part of the Asteroid Impact & Deflection Assessment (AIDA) International collaboration with NASA
who is responsible for the DART (Double Asteroid Redirection Test) kinetic impactor spacecraft. Hera will be launched in
October 2024 and will arrive at Didymos binary asteroid in January 2027. Milani CubeSat (fig. 1) is developed by Tyvak
International with a consortium of European universities, research centers and firms from Italy, Czech Republic and Finland.
At arrival it will be deployed and will do independent detailed characterization of Didymos asteroids at distances 5 to 10 km
supporting Hera observations. Milani mission objectives are:
1. Map the global composition of the Didymos asteroids.
2. Characterize the surface of the Didymos asteroids.
3. Evaluate DART impacts effects on Didymos asteroids and support gravity field determination.
4. Characterize dust clouds around the Didymos asteroids.
The scientific payloads supporting the achievement of these objectives are “ASPECT”, a visible - near-infrared imaging
spectrometer (table 1), and “VISTA”, a thermogravimeter (table 2) aiming at collecting and characterizing volatiles and dust
particles below 10μm.

Figure 1.

Milani CubeSat

T able 1.

ASPECT specifications
Channel
VIS
Field of View [deg]10° x 10°Spectral range [nm]500 – 900
Image size [pixels]
1024 x 1024
Pixel size [µm]5.5 µm x 5.5 µm
No. spectral bands
Ca. 14
Spectral resolution [nm]< 20 nm

T able 2.

VIST A specifications
Sensor T ype
Resonance frequency
VolumeSensitive area
Particles size detection range
Methods/T echnique used
Mass

NIR1
6.7° x 5.4°
850 – 1275
640 x 512
15 µm x 15 µm
Ca. 14< 40 nm

NIR2
6.7° x 5.4°
1225 - 1650
640 x 512
15 µm x 15 µm
Ca. 14< 40 nmSWIR
5° circular
1600 - 2500
1 pixel
1 mm
Ca. 30< 40 nm

Quartz Crystal Microbalance (QCM)
10 MHz50mm × 50mm × 38mm
1.5cm^2
5-10 μm to sub-μm particles
1. Dust and contaminants accumulation (passive mode)
2. T GA cycles (active mode)
90g

The young basalts on the Moon: Pb–Pb isochron dating in Chang’e-5 Basalt
CE5C0000YJYX03501GP
Dunyi Liu1,3, Alexander Nemchin2,1, Xiaochao Che1, Tao Long1, Chen Wang1, Marc D. Norman4, Katherine H. Joy5, Romain
Tartese5, James Head6, Bradley Jolliff 7, Joshua F. Snape5, Clive R. Neal8, Martin J. Whitehouse9, Carolyn Crow10, Gretchen
Benedix2, Fred Jourdan2, Zhiqing Yang1, Chun Yang1, Jianhui Liu1, Shiwen Xie1, Zemin Bao1, Runlong Fan1, Dapeng Li3,
Zengsheng Li3, Stuart G. Webb8
1

Beijing SHRIMPCenter, Institute of Geology, Chinese Academy of Geological Sciences. 2School of Earth and Planetary
Sciences, Curtin University. 3Shandong Institute of Geological Sciences, Jinan, Shandong. 4Research School of Earth Sciences,
The Australian National University. 5Department of Earth and Environmental Sciences, The University of Manchester.
6
Department of Earth, Environmental, and Planetary Sciences, Brown University. 7Department of Earth and Planetary
Sciences and The McDonnell Center for the Space Sciences, Washington University in St. Louis, St. Louis. 8Department ofCivil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame. 9Department ofGeosciences, Swedish Museum of Natural History. 10Department of Geological Sciences, University of Colorado Boulder.

Figure 1. A & B false color energy EDS element maps of the two fragments from CE5C0000YJYX03501GP blue=silica, green=Mg, red=Fe,
white=Al, yellow=Ca, pink=Ti, cyan=K. C Pb-Pb isochrons for CE5C0000YJYX03501GP.

China’s Chang’e-5 mission collected 1731g lunar samples at 43.1°N, 51.8°W in the northeastern Oceanus Procellarum of theMoon. Basalt fragments is the main lithic type in the lunar soil returned by Chang’e-5 that showed five distinct textural
types[1], The two scooped basalt fragments from CE5C0000YJYX03501GP both are equidimensional, approximately 3-4 mm
in size and consist of clinopyroxene, plagioclase, olivine, ilmenite, quartz, cristobalite, K-rich glass, barian K-feldspar, troilite
and Ca-phosphates, with small amounts of the Zr-rich minerals baddeleyite and zirconolite[Figure 1. A, B]. The pyroxenes andolivines in the two fragments include highly Fe-rich compositions for lunar basalts. and the bulk compositions of bothfragments indicate elevated FeO (~22-25 wt.%) and low MgO (~5 wt.%). The mineralogy and bulk compositions of two basalt
fragments are consistent with remote sensing data of this region [2]. These 677 ± 3 of 238U/204Pb ratio (μ-value) for the two
fragments imply only a modest (<2%) KREEP component either in their mantle sources or introduced by assimilation duringmagma ascent [2].
The Pb isotope data were collected using a SHRIMP IIe-MC at Beijing SHRIMP Center, Institute of Geology, Chinese
Academy of Geological Sciences, Beijing. 204Pb+, 206Pb+, 207Pb+ and 208Pb+ isotopes were measured simultaneously with multicollectors and the 204Pb/206Pb, 207Pb/206Pb and 208Pb/206Pb ratios were calibrated using BCR-2, BHVO-2. Combining all Pb
isotope data from Zr-rich minerals, Ca-phosphates, K-rich glass and barian K-feldspar for the two basalt fragments, gives anisochron age of 1963 ± 57 Ma [Figure 1. C]. This age constrains the lunar impact chronology of the inner Solar System and thethermal evolution of the Moon. Studies of other basalt fragments from Chang’e-5 have yielded similar results [3, 4], andshowed a relatively low water content [5].
Reference[1] Li C. et al. 2021. National Science Review. [2] Che X. et al. 2021. Science. [3] Li Q. et al. 2021. Nature. [4] Tian H. et al.
2021. Nature. [5] Hu S. et al. 2021. Nature.

The fundamental deformation of cosmic bodies not depending of their sizes and compositions (fromasteroids to Universe)
Kochemasov G. G. IGEM RAS,Moscow,kochem.36@mail.ru
Abstract: Orbits make structures. Not depending sizes and compositions of celestial bodies they acquire
tectonic dichotomy (two hemispheres) connected with warping action of fundamental wave.
Keywords; cosmic bodies. orbits, galaxies, planets, satellites, asteroids, fundamental wave
The main point of the wave planetology is: “Orbits make structures”. It means that movement in nonround orbits makes waves creating structures (Fig. 1-10) However, any cosmic body moves in several
orbits. They all participate in structuring [1]. Their frequencies are divided and multiplied creating new
frequencies and corresponding them structures. They are (frequencies) very small and very big. Veryslow but very energetic rotation of large cosmic formations (galaxies and the larger assemblies) makevery fine oscillations up to microwaves, roentgen and gamma radiations infilling cosmos. From theother end, oscillations passed through fundamental wave and corresponding it tectonic dichotomy ofany body. In figures are examples of bodies of various sizes from the Galaxy to small asteroids (Fig.1-8)
The row is finished with small asteroids Itokawa and Ryugu. Both reveal tectonic dichotomy;
especially sharp in Itokawa with its convexo-concave shape. Ryugu has unique longitudinal variation ingeomorphology: the western side of it has a smooth surface and a sharp equatorial ridge (bulge) [3]. On
the opposite side Fossae Tokoyo and Horai occur. Some peculiarities show crater distribution (morethan 20 meters in diameter). There are fewer craters in the western bulge and more around themeridian. This cannot be explained by the randomness of cratering [2].
The other end of this row include giant cosmic formations like galaxies and larger ones finishing atUniverse. The Universe also is dichotomist divided at uplifted and subsided halves. The humankind
occupies the uplifted halve-in the religious sense “paradise”, the subsided halve thus is “hell”.

1

2Fig, 1. A spiral Galaxy. ESO 510-613. PIA04213.
Fig.2. PIA22113.Coronal hole all spread out.

3
Fig. 3. PIA23356. NASA’s AIRS maps carbon monoxide from Brazil fires.

4

Fig. 4. PIA14011. Moon’s nearside

5

6

Fig. 5. Asteroid Eros. Convexo-concave shape.
Fig. 6. Asteroid Itokawa. Convexo-concave shape.

78Fig. 7. Asteroid Ryugu. Ab278776d6ce43e581d669ef938497fa.jpg
Fig. 8. Asteroid Ryugu. Dichotomy shows.image_5c91c15458e6c0.69646182.jpg

9

10

Fig.9, 10. Fundamental wave in line and circle.
Referencs:[1] Kochemasov G.G. Modulated wave frequencies in the Solar system and Universe // Journalof Physics and Application 12(4): 68-75, 2018. Doi:10.13189/ujpa.2018.120402.
[2 ] N.Hirata, T. Morota, Y.Cho et al. The spatial distribution of impact craters on Ryugu// Icarus , v.338,
1, March 2020, 113527, httys:// doi.org/10.1016/j.icarus.2019.113527[3] ] H. Masatoshi, T. Eri, M. Hideaki et al. The western Bulge of 162173Ryugu formed as a result of arotationally driven deformation process // The Astronomical Journal: journal-IOP Publishing, 2019March (vol.874, #1-P. L10.-ISSN 0004-637X-doi:10.3847/2041-8213/ab0e8b-Bibcode:
2019ApJ…874L.10N-arXiv:1904.03480.

Exogenous copper sulfide in a returned grain from asteroid Itokawa
K. D. Burgess and R. M. Stroud
U.S. Naval Research Laboratory, Washington, DC 20375
Asteroid 25143 Itokawa is an S-type asteroid, and the returned samples are dominated by equilibrated, weakly shocked LL5
and LL6 ordinary chondrite material with some weakly equilibrated LL4 material [1,2]. We present evidence of the presenceof a cubanite-chalcopyrite-pyrrhotite-troilite assemblage consistent with low-temperature aqueous alteration in a particle from
Itokawa [3]. Most of the materials from Itokawa equilibrated at temperatures near 800°C, with slow cooling to ~600°C [2,4],
which indicates this sulfide assemblage must have become part of Itokawa after thermal alteration. Cu-bearing sulfides havebeen reported in only a few meteorite types [5,6], which suggests the conditions necessary to form such phases occur on only alimited number of planetary bodies. Specifically, cubanite has only been reported in CI chondrites and Wild2 material [7].
Thus, we conclude that this grain, and the other Cu-sulfides noted on Itokawa samples [8] likely originated on a primitive,
hydrated asteroid source such as CI chondrite-like parent body or D- or P-type asteroids previously linked to unique, aqueously
altered meteorites [9,10].
Particle RB-CV-0038 (C0038) was mounted in epoxy such that most of the grain was available for imaging, then coated by 80
nm of evaporated carbon. SEM images and FIB samples were obtained with an FEI Helios G3 equipped with an Oxford 150
mm2 SDD energy dispersive X-ray spectrometer (EDS). After imaging, protective straps of C were deposited on regions ofinterest, and multiple sections suitable for STEM analysis were extracted using standard techniques. One section, known from
SEM-EDS to contain Cu, was attached to a Mo grid. STEM analysis was performed with the Nion UltraSTEM200-X at NRL.
The microscope is equipped with a Gatan Enfinium ER spectrometer for electron energy loss spectroscopy (EELS) and awindowless, 0.7 sr Bruker SDD-EDS detector. Selected area diffraction patterns were collected using a JEOL 2200FS. Data
were collected at 200 kV.

Figure 1. (a,b) Secondary electron (SE) images of particle RB-CV-0038 showing location of cubanite with Fe-sulfide and approximate
location of FIB section. (c) HAADF montage of FIB section with cubnaite (cb), troilite-cubanite-chalcopyrite (tr+cb+cp) mottled region, andpyrrhotite (4C-po) with “flame” texture.

C0038 is a multiphase grain, ~40 µm across. The particle is predominantly composed of olivine and iron sulfide with minor(adhered?) plagioclase or glass (Fig. 1a). A ~2×5 µm cubanite grain was present in contact with the Fe-sulfide (Fig. 1b). STEM
data show several different grains are present within the Fe-sulfide in the FIB section (Fig. 1c). The Cu-Fe-sulfide contains
several cracks are, one of which is perpendicular to the FIB section (Fig. 2a). The crack has oxidized Fe-rich edges and isdecorated by Cu metal nanoparticles. The cubanite itself shows a tripling of the c axis, apparent in SAED patterns (Fig. 2b).
Adjacent to the cubanite, the sulfide has a mottled texture (Fig. 2a), and a small amount of Cu is present (~2 at%), concentrated
in the bright spots. SAED patterns from the region index to troilite with faint chalcopyrite spots (Fig. 2d). Further from thechalcopyrite, there is no Cu, and the Fe-sulfide has a “flame” exsolution texture of two types of pyrrhotite (Fig. 2c). The
pyrrhotite can be indexed to 4C-pyrrhotite. The average measured Fe/S composition for the grain (x = ~0.09 in Fe1-xS) is
consistent with a 4C-pyrrhotite or a mixture of 4C and NC-pyrrhotites. In NC-pyrrhotites, NC indicates a variable, non-integral
superstructure based on the NiAs-type unit cell where troilite is 2C.

Figure 2. (a,c) HAADF images of cubanite, mottled Fe-sulfide, and pyrrhotite with flame texture. (b) SAED pattern for the cubanite, whichshows a tripling of the c axis. (d) SAED pattern for the mottled Fe-sulfide, which has ~2 at% Cu and shows reflections for cubanite andchalcopyrite in addition to troilite.

The presence of cubanite, which forms and is stable only at temperatures below ~250°C [11], together in this grain with 4Cpyrrhotite [7], indicates that this grain must have been brought to Itokawa after thermal alteration and equilibration of the LLtype material. This combination of sulfide phases has previously been identified only in CI chondrite material [7]. However,unlike CI chondrites, no Ni was detected in these sulfides. This could indicate variation in the CI parent body, or that the
impactor seen here was from a different parent body, such as the aqueously altered D- or P-type asteroids.
Acknowledgements
The authors thank JAXA and the Hayabusa curation team for access to the samples. Funding was provided by NASA LARS
award 80HQTR20T0050 and NNH17AE44I to RMS.
References[1] Mikouchi, T., et al. (2014) Earth, Planets and Space, 66, 82. [2] Noguchi, T., et al. (2011) Science, 333, 1121. [3] Burgess,
K.D., and Stroud, R.M. (2021) Communications Earth & Environment, 2, 115. [4] Harries, D., and Langenhorst, F. (2018)
Geochimica et Cosmochimica Acta, 222, 53. [5] Rubin, A.E. (1997) Meteoritics & Planetary Science, 32, 231. [6] Rubin, A.E.,
and Ma, C. (2017) Geochemistry, 77, 325. [7] Berger, E.L., et al. (2011) Geochimica et Cosmochimica Acta, 75, 3501. [8]Nakamura, E., et al. (2012) Proceedings of the National Academy of Sciences of the United States of America, 109, E624. [9]Brown, P.G., et al. (2000) Science, 290, 320. [10] Kebukawa, Y., et al. (2019) Scientific Reports, 9, 3169. [11] Dutrizac, J.
(1976) The Canadian Mineralogist, 14, 172.

A Series of Recent Falls of Carbonaceous Chondrites - Perfect Analogues for Returned
Hayabusa 2 and Osiris Rex Asteroidal Materials
V.H. Hoffmann1, K. Wimmer2, M. Kaliwoda1,3, W. Schmahl1,3, P. Schmitt-Kopplin4. 1Faculty of Geosciences, Dep. Earthand Environmental Sciences, Univ. Munich; 2Nördlingen; 3Mineralogical State Collection Munich, SNSB; 4Helmholtz-Center,
Munich; Germany.
Introduction
In recent years, a series of meteorite falls have been reported which produced various types of primitive chondrites. In ourcontribution we will focus on samples of the following witnessed falls: Flensburg (2019), Kolang and Tarda (both 2020), while
Mukundpura (fall 2017) was topic of our earlier studies [1-3]. These meteorites belong to the class of carbonaceous chondrites
and play a prominent role in terms of the Hayabusa 2 (successful sample return from asteroid Ryugu in December 2020) andOsiris Rex (sample return from asteroid Bennu planned in 2023) missions [4,5] Both probed asteroids belong to the C typeasteroids and are believed to mainly consist of carbon rich materials with a similar composition as primitive chondrites.
The Flensburg meteorite fell in September 2019 in Northern Germany and was classified as a C1 ungrouped carbonaceouschondrite, the first reported fall of this type. Only one small stone was found so far (24.5 gr). For all further details we refer to[2]. The Tarda meteorite fall was reported from Southern Morocco in august 2020, the meteorite (about 4 kg total mass) wasclassified as a C2 ungrouped carbonaceous chondrite [1,2,6,7]. Only four witnessed falls of this type are known, whereby
Tagish Lake is probably the most famous one (fall 2000, [1]). The Kolang meteorite fireball and fall was reportedly observedin Indonesia in august 2020 (four stones with a total mass of 2550 gr). Kolang was classified as a CM 1/2 chondrite and is thefirst and only witnessed fall known from this meteorite group [8,9].
In our contribution (poster) we will compile our earlier and provide new results of detailed and systematic investigations on themineral phase composition and distribution of three new meteorite falls [10,11]. Our focus was mainly on the rare/accessory
mineralogical components of these meteorites. Specifically we are interested on the carbon-bearing and the magnetic phases.
Several unprepared fragments and one individual of Tarda were used for our studies, and additionally one small unpreparedfragment of Kolang. Concerning Flensburg, we had a small fragment and a PTS (provided by A. Bischoff, Univ. Münster). We
used optical microscopy, LASER Micro Raman Spectroscopy (Horiba XploRa Raman System, MSM/ SNSB) for our study
which is perfectly suited for identifying and mapping minor/accessory phases. Being fully non-destructive, allowing highresolution mapping on natural, broken surfaces without any preparation in 2D or 3D are some of the major advantages of thistechnique. The surface morphology and mineralogy of the uncoated samples was investigated using a Phenom ProX scanningelectron microscope (SEM) in backscattered electron mode equipped with an energy dispersive X-ray spectrometer (EDS) foranalyzing the element composition. Magnetic susceptibility was investigated systematically by an SM30 (Hulka Comp., CR).
The results of our Raman spectroscopy experiments on Kolang have to be seen as preliminary as we had only one small
fragment for our project. Generally, performing successful LASER Raman experiments on carbonaceous chondrites, here
specifically on Flensburg, Tarda and Kolang, required the design of a highly sophisticated experimental setup to avoid or atleast minimize alteration effects already during the measurements on the one hand and to guarantee a reasonable signal/noise
relationship on the other. Due to the significant brecciation and very fine grained matrix / phases, experiments on Kolang arequite complex. Generally, several phases which have been detected in these primitive carbonaceous chondrites are extremely
sensitive against (even minor) heating effects, and therefore any kind of preparation (cutting/grinding etc.), specifically interrestrial atmospheric conditions has to be minimized. In order to avoid any such effects we decided to investigate only
naturally broken unprepared sample materials (PTS of Flensburg is a necessary exception because of representativity but wealso had a fragment). The representativity of the data obtained on the available sample material was also topic of our studies:large sets of high resolution mappings in 2D/3D can help to overcome the problem of tiny samples / fragments. Our
experiences from the earlier investigations on Hayabusa 1 materials (asteroid Itokawa) were highly profitable in this context[12-14].
Consequently, our main interests were on optimizing and fine tuning our experimental setup. So the series of recent meteorite
falls which produced a new set of primitive carbonaceous chondrites provided us directly with unique fresh analogue materials
for Hayabusa 2 and Bennu asteroidal samples in our laboratories. We plan to extend our investigations in near future to
additional recent falls such as Aquas Zarcas (2019, Costa Rica, CM2) or most recently Winchcombe (2021, England/UK,
CM2) [1,3].

References[1] Meteor. Bull. Database 10/2021: Flensburg , Tarda, Kolang, Aquas Zarcas, Winchcombe, Mukundpura, Tagish Lake.
[2] Bischoff A. et al., 2021. The old, unique C1 chondrite Flensburg – Insight into the rst processes of aqueous alteration,
brecciation, and the diversity of water-bearing parent bodies and lithologies. Geochem. Cosmochem. Acta, 293, 142-186.
[3] https://www.karmaka.de (10/2021)[4] Hayabusa 2 mission to asteroid Ryugu (finished 12/2020), JAXA: https://www.hayabusa2.jaxa.jp/en/[5] Osiris Rex mission to asteroid Bennu, NASA: https://www.nasa.gov/osiris-rex[6] Chennaoui H.A., et al., 2021. Tarda (C2-ung): a new and unusual carbonaceous chondrite meteorite fall from Morocco.
52nd LPSC 2021, #1928.
[7] Dey S., et al., 2021. Exploring the planetary genealogy of Tarda – a unique new carbonaceous chondrite. 52nd LPSC 2021,# 2517.
[8] King A.J., et al., 2021. The bulk mineralogy and water contents of the carbonaceous chondrite falls Kolang and Tarda. 52nd
LPSC 2021, #1909.
[9] Jenkins L.E., et al., 2021. Identification of clasts in CM chondrite fall Kolang with S and Ca. 84th Meteor. Soc. Conf.,#6161.
[10] Hoffmann V., et al., 2021. The Kolang (CM1/2) and Tarda (C2 ungrouped) meteorite falls from 2020: first systematic
mineralogical investigations by LASER Raman spectroscopy and SEM/EDX. 52nd LPSC 2021, # 2458.
[11] Hoffmann V., et al., 2021. The Flensburg (C1 ungrouped) 2019 meteorite fall: Raman spectroscopy and compilation ofmagnetic susceptibility data on C-ungrouped falls/finds. 52nd LPSC 2021, # 2443.
[12] Mikouchi T., Hoffmann V.H. et. al., 2014. Mineralogy and crystallography of some Itokawa particles returned by the
Hayabusa mission. LPSC 2021, #2239.
[13] Mikouchi T., Hoffmann V.H., et al., 2013. Mineralogy and crystallography of Itokawa particles by electron beam andsynchrotron radiation X-ray analyses. Hayabusa Conf. 2013.
[14] Mikouchi T. and Hayabusa Consortium, 2014. Mineralogy and crystallography of some Itokawa particles returned by the
Hayabusa asteroidal sample return mission. Earth, Planets and Space, 66/82, 9pp.

Heated Synthetic Murchison Reflectance Spectra

1

S. Sidhu1, P. Mann2 and E. Cloutis1
Centre for Terrestrial and Planetary Exploration (C-TAPE), The University of Winnipeg
2
Department of Geography, The University of Winnipeg

Introduction: Several carbonaceous chondrites (CCs) display evidence of thermal alteration [1]. Remote sensing data from the
JAXA Hayabusa2 asteroid sample return mission suggests that asteroid (162173) Ryugu’s parent body may have undergoneinternal or impact-generated heating prior to breakup [2]. Furthermore, models of orbital and thermal evolution of Ryugu suggestthat the asteroid was likely exposed to surficial heating during close passes to the Sun. [3]. Recently, geomorphological features
observed on Bennu’s surface indicate alteration of rocks due to thermal fatigue [4]. Constraining the spectral characteristics ofheating will aid in identifying the timing and intensity of heating experienced by Ryugu and its parent body, as well as otherextraterrestrial bodies which may have also undergone a period of thermal alteration.
Methods: The Centre for Terrestrial and Planetary Exploration (C-TAPE) at the University of Winnipeg conducted aheating experiment on a synthetic Murchison simulant. The synthetic mixture, named WMM, consisted of various major
representative phases in CM carbonaceous chondrites as following: 85 wt. % ASB267, a dark serpentinite representative of CM
phyllosilicates. 5 wt. % SHU102, shungite, terrestrial organic representative of organic phases. 5 wt. % TRO203, synthetic
troilite representative of sulfides, and 5 wt. % MAG200, magnetite. The simulant consisted of <63 µm powders of serpentinite,shungite, and troilite, and ~20 nm sized magnetite that appeared to be maghemite from X-ray diffractometry (likely due to surface
oxidation of the nanoparticles). The samples were heated up to 1200qC at 100qC increments. XRD and reflectance spectra werecollected prior to heating, and after each temperature increment. A new sample powder was used for each increment, and samples
were heated under continuous nitrogen flow. Samples were heated for one week at intervals of 100qC to 1000qC. However, due
to the oven’s constraints, samples were only heated for 2 hours at 1100qC and half an hour at 1200qC. The reflectance spectrum
for 300qC is unavailable due to an accidental sample spill while removing the powder from the oven. The spectra were collectedwith an Analytical Spectral Devices (Boulder, CO) LabSpec 4 Hi-Res® spectrophotometer between 350 and 2500 nm. Spectra
were measured at a viewing geometry of i = 30º and e = 0º with incident light being provided by an in-house 150 W quartztungsten-halogen collimated light source. Sample spectra were measured relative to a Labsphere Spectralon ® 100% diffuse
reflectance standard and corrected for minor (less than ~2%) irregularities in its absolute reflectance.
Results: Heating the Murchison simulant samples resulted in spectral variation across the temperature increments. The
spectra show little change up to ~500qC (Figure 1). Beyond 500qC, the spectra display features associated with Fe3+
oxyhydroxides, such as low reflectance below ~500nm, a steep red slope in the visible region, and absorption features near 870
nm. Absorption bands associated with serpentine, at 1400 and 2320 nm, are evident up to ~600-700qC. The spectra generally
become brighter up to ~800qC, and then darken substantially beyond this temperature. At and above 1100qC, the spectra are
generally dark and featureless, with a broad absorption region centered near 1600 nm.
1Absolute Reflectance

0.8
0.6
0.4
0.2
0
300

800
Before Heating
500°C
900°C
Figure 1.

100°C
600°C
1000°C

1300
1800
Wavelength (nm)
200°C
700°C
1100°C

Reflectance Spectra of Simulated Murchison Mixture WMM.

2300
400°C
800°C
1200°C

Additionally, we heated end members used to produce the Murchison simulant to better understand the causes of thespectral changes observed. These samples (serpentine, shungite, troilite, and magnetite) were heated under the same conditions
as the simulant. Serpentine spectra remained unchanged up to ~200qC, after which the spectra display an increasing red slope
below ~700 nm and an absorption feature near 860 nm, both of which are ascribed to Fe3+ oxyhydroxides. Furthermore, theOH absorption bands near 1400 and 2320 nm associated with serpentine were evident up to ~700qC. Reflectance generally
increased up to ~600qC, and decreased at higher temperatures. Shungite was stable up to ~500qC. However, at 600qC, theorganic component of the sample was volatilized. Troilite remained stable up to ~300qC, after which Fe3+ oxyhydroxides were
evident in its spectra. Fine-grained magnetite remained stable up to ~100qC, after which it also transformed to Fe3+
oxyhydroxides.
Discussion: Temperature-induced spectral changes are evident in the Murchison simulant used in this study. XRD
measurements confirm that the changes seen in the spectra can be related to the changes in the mineralogy of the samples. The
spectral changes occur in multiple wavelength regions, suggesting that various spectral metrics could be robust indicators oftemperatures experienced by a serpentine-rich carbonaceous chondrite.
Spectral changes observed in this study are associated with short heating periods (hours to days), and are thus,
applicable to short-term heating events such as impact heating. The applicability of these results to long-term heating events,
such as internal heating within larger asteroids, is unknown. Furthermore, the dry nitrogen environment under which thisheating experiment was conducted only represents one scenario of the conditions which may have prevailed on carbonaceouschondrite parent bodies during any heating events. Nevertheless, the results of our experiments suggest that spectroscopic datain the 350-2500 nm can provide insights into the intensity and duration of heating events affecting carbonaceous chondrite
asteroids. It is also worth noting that naturally-heated carbonaceous chondrites show spectral differences associated withchanges in mineralogy [1]. We are in the process of relating the results of these experiments to other carbonaceous chondrite
heating experiments [5, 6, 7, 8] and naturally-heated carbonaceous chondrites [9] to better understand the full applicability of
our results to observational data.
References[1] Cloutis E. et al. 2012. Icarus 220:586-617. [2] Sugita S. et al. 2019. Science 6437:252. [3] Michel P. & Delbo M. 2010.
Icarus 209:520-534. [4] Molaro J.L. et al. 2020. Nature Communications 11:2913. [5] Hiroi T. et al. 1993. Science 261:10161018. [6] Hiroi T. et al. 1993. Symposium on Antarctic Meteorites 18:93-96. [7] Hiroi T. et al. 1994. Proceedings of the NIPR
Symposium on Antarctic Meteorites 7:230-243. [8] Hiroi T. et al. 1996. Meteoritics and Planetary Science 31:321-327. [9]Hiroi T. et al. 1997. Lunar and Planetary Science Conference 28:577-578.

Status of the Curatorial Database System for the Ryugu Samples
M. Nishimura1, T. Yada1, M. Abe1, A. Nakato1, K. Yogata1, A. Miyazaki1, K. Kumagai2, K. Hatakeda2,
T. Okada1, Y. Hitomi2, H. Soejima2, K. Nagashima1, T. Usui1, and S. Tachibana1,3
1Inst. Space Astronaut. Sci. (ISAS), Japan Aerosp. Explor. Agency (JAXA), Kanagawa 252-5210, Japan(nishimura.masahiro2@jaxa.jp), Japan, 2Marine Works Japan Ltd., Yokosuka 237-0063, Japan, 3UTOPS, Grad. Sch. Sci.,
Univ. Tokyo, Tokyo 113-0033

The JAXA’s Hayabusa2 spacecraft explored C-type near-Earth asteroid (162173) Ryugu and successfully returned its
reentry capsule on December 6, 2020. Particles exceeding ~5 grams in total were safely extracted from two sample chambersin the clean chamber system dedicated to Ryugu samples [1, 2]. After a six-month preliminary examination without exposure
to the air by the JAXA Astromaterials Research Group (ASRG), a part of Ryugu samples have been studied by the initial
analysis team led by the Hayabusa2 project [3]. Some samples have also been characterized by Phase-2 curation teams outside
ASRG [4]. The rest of the samples are continued to be investigated in the clean chamber to be catalogued in a curatorial
database system for Ryugu samples (Ryugu DBS), which will be archived to the community in early 2022 for theannouncement of opportunity (AO). In this presentation, we report the aim and features of the Ryugu DBS.
The Ryugu DBS has been designed and built to provide the Ryugu sample catalog with the research community andto help the researchers make the sample request through the announcement of opportunity.
The concept design of the Ryugu DBS was made in md 2019 based on lessons-learned from the operation of DBS for Itokawa
samples (Itokawa DBS) [5]. A mockup was first made to check the web interface and the user-friendliness of the system inearly 2020. The database system was then developed based on the feedback from the mockup review in Oct. 2020. The system
has been used by limited members for further feedback, major updates were made, and a supplemental system such as a data
input system was also developed. The Ryugu DBS is run using opensource technologies, such as PHP, PostgreSQL, andApache, and data servers on Data ARchives and Transmission System (DARTS) at ISAS/JAXA.
The Ryugu DBS provides the information on each individual grain (typically larger than 1 mm along the longest
dimension) and on aggregate samples. Because of the presence of large amount of fine particles (relative to Itokawa particles),fine grains are planned to be examined as an aggregate sample put in a single dish. The basic information listed in the DBS
includes photomicrographs, weight, size, and spectroscopic data, all of which are obtained in the clean chamber system
without exposure to the air. The spectroscopic data can be downloaded with the CSV format. Along with such basic
information, the analysis history and data obtained in previous analysis can also be found for each sample. The data obtainedby the project-led initial analysis and that from curation work outside JAXA will also be archived in the future.
The release of the Ryugu DBS to the community will be in early 2022.
References[1] Tachibana S. et al. (2021) LPS, XXXXXII, Abstract #1289. [2] Yada T. et al. (2021) LPS, XXXXXII, Abstract #2008. [3]Tachibana S. et al. (2021) submitting for Hayabusa 2021 symposium. [4] Ito M. et al. (2021) submitting for Hayabusa 2021
symposium. [5] Uesugi M et al. (2016) Journal of Space Science Informatics Japan: Vol 5, 59-70.

Fig. 1. The interface of the Ryugu DBS.

Methodology of MicrOmega data acquisition/processing in initial description of
Ryugu returned samples
Kasumi Yogata1, Tatsuaki Okada1,2, Kentaro Hatakeda1,3, Toru Yada1, Masahiro Nishimura1, Aiko Nakato1, Akiko Miyazaki1,
Kazuya Kumagai1,3, Yuya Hitomi1,3, Hiromichi Soejima1,3, Kana Nagashima1, Ritsuko Sawada1,3, Shogo Tachibana1,2,
Masanao Abe1,4, Tomohiro Usui1, Jean-Pierre Bibring5, Cedric Pilorget5, Vincent Hamm5, Rosario Brunetto5, Damien
Loizeau5, Lucie Riu1,5, Lionel Lourit5, Guillaume Lequertier5, and Hayabusa2 MicrOmega-Curation team1,51Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 2University of Tokyo, 3Marine Works
Japan, Ltd., 4The Graduate University for Advanced Studies (SOKENDAI), 5Institut d'Astrophysique Spatiale, Université
Paris-Saclay
The Hayabusa2 spacecraft successfully brought samples back to Earth in December 2020, collected at two different
locations on the surface of the C-type asteroid Ryugu. The samples, weighing about 5.4 g, have been transported to theExtraterrestrial Samples Curation Center of JAXA and have been installed in vacuum chambers or pure nitrogen-purgedchambers. JAXA curation is currently in the progress of producing catalog data to be included in the database, which is planned
to be open in early 2022 towards sample allocation for Announcement of Opportunity [2]. Within this work, basic properties ofreturn samples, for both the aggregate and individually picked-up grains, are acquired using microscopy, weighing, andvisible/near-infrared spectroscopy and imaging analyzer. One of the methods is near-infrared hyperspectral microscopy by
MicrOmega, developed at IAS (Orsay, France) [3].
MicrOmega is installed in a class 1000 clean room, in contact with a sapphire viewport window of a nitrogen-purged
clean chamber. By distant monochromatic light illumination of MicrOmega, it enables non-destructive ultraclean analysis
without exposure of the samples to the atmosphere and protecting them from contamination such as water and human-derived
organics. MicrOmega has a 5x5 mm Field of View (FOV) and 250x256 pixels with a resolution of 22.5 µm/pixel, and generates
a hyperspectral (x,y,λ) cube within the 0.99 to 3.65 µm wavelength range. The performance above can mark the presence ofabsorption bands suggestive of hydrous minerals at 1.4, 1.9, and 2.7-3.0 µm, and of organics and carbonates at 3.4 µm. Also, its
FOV can cover the entire body of a single grain, most of which are about a few mm in size, and the image resolution allows to
distinguish interstitial materials such as meteoritic inclusions more than 50-100 µm in diameter.
In the production of data for the catalog, it is important to be careful about the shape-dependent signals of grains. The
image often shows strong specular reflection and/or the shadow effect at a certain angle due to the instrument's light illumination
incidence angle: 35 degrees. Therefore, for the catalog, two monochromatic images with different angles are generated for eachsingle grain to show the effect of angular dependence. In addition, since the FOV usually includes signal from the sapphire
sample dish where the grain sits, we extract the average spectra of the grain area only. Furthermore, if there are areas that show
distinctive signatures different from most of the others, specific ROIs are also extracted. The database will contain images
showing the ROIs and their spectral data, with comments on the inclusions and minerals they may imply.
In this presentation, we will introduce the MicrOmega data acquisition and data processing, including approaches in
the presence of angle-dependent effects and sorting strategies for the curatorial initial description, and the characteristics oftypical samples based on results obtained so far for each individual grain.

Figure 1. (a) Monochromatic image of A0015 grain at 2.50um at 0 deg,

Figure 2. Average reflectance of A0015

and (b) at 180 deg, showing angular dependence on the reflectance.

at different angles and focal positions.

References: [1] Yada et al. submitted to Nature Astron., [2] Nishimura M. et al. (2021), Astromaterials Data Management in
the Era of Sample-Return Missions Community Workshop, Abstract, [3] Pilorget et al. submitted to Nature Astron.

Comparison of ion- and laser-weathered spectra of olivines and pyroxenes
K. Chrbolková1,2,3, R. Brunetto4, J. Ďurech2, T. Kohout1,3, K. Mizohata5, P. Malý6, V. Dědič7, C. Lantz4, A. Penttilä8, F.
Trojánek6, and A. Maturilli9
1
Department of Geosciences and Geography, University of Helsinki, Gustaf Hällströmin katu 2, 00560 Helsinki, Finland(katerina.chrbolkova@helsinki.fi)
2
Astronomical Institute of Charles University, V Holešovičkách 2, 18000 Prague 8, Czech Republic
3
Institute of Geology, The Czech Academy of Sciences, Rozvojová 269, 16500 Prague 6, Czech Republic
4
Université Paris-Saclay, CNRS, Institut d'Astrophysique Spatiale, 91405 Orsay, France
5
Department of Physics, Faculty of Science, University of Helsinki, Pietari Kalmin katu 2, 00560 Helsinki, Finland
6
Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 12116
Prague, Czech Republic
7
Institute of Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 12116 Prague, Czech Republic
8
Department of Physics, Faculty of Science, University of Helsinki, Gustaf Hällströmin katu 2, 00560 Helsinki, Finland
9
Institute of Planetary Research, DLR German Aerospace Centre, Rutherfordstrasse 2, 12489 Berlin, Germany

Introduction: Irradiation by solar wind ions and impacts of micrometeoroids are the leading processes that weather surfacesof airless planetary bodies in the solar system. As a result, key diagnostic features of their spectra get altered. The mostprominent changes in the silicate-rich bodies in the visible (VIS) and near-infrared (NIR) wavelengths are increase in the
spectral slope, reduction of the albedo, and flattening of the mineral absorption bands (see, for example, [1]).
Our laboratory experiments aimed at understanding what are the similarities and differences between the effect of the solar
wind ions and micrometeoroid impacts on the final spectra of the silicate-rich bodies.
Methods: We have used two different terrestrial minerals, olivine and pyroxene, which we ground , dry-sieved, and pressed
into pellets.
Hydrogen (H) irradiations proceeded at the Accelerator Laboratory of the University of Helsinki, using 5 keV ions withvarying fluences from 1014 to 1018 ions/cm2. Helium and argon irradiations were done using the INGMAR set-up (IASCSNSM, Orsay) with 20 and 40 keV ions and with fluences from 1015 to 1017 ions/cm2.
Individual 100-fs laser pulses were shot into a square grid on the pellets’ surface to simulate the micrometeoroid impacts (as in[2]) in the laboratories at Charles University. Various densities of the pulses per cm 2 simulated different weathering stages.
Subsequent spectral measurements covered wavelengths from 0.54 to 13 μm, i.e. VIS to mid-infrared wavelengths. After themeasurements, we evaluated the evolution of the spectral parameters estimated using the Modified Gaussian Model [3, 4].
Results: We found that the variation of the spectra in the VIS range was similar for H+- and laser-irradiated samples, but wehave identified a difference in the NIR wavelength range. Laser irradiation caused greater changes in NIR than any of the ions
we used, see Fig. 1. The reason for such difference in behaviour may be that the penetration depth of the laser pulses is muchlarger than in the case of the ions. The relative contribution of the irradiated material in the spectra is then smaller in the ioncase than in the laser case.
Otherwise, we found that the original mineralogy of the surface is the leading factor influencing the evolution of the spectral
parameters. While olivine and pyroxene showed albedo variations of a similar order, the evolution of pyroxene’s spectral slope
was negligible when compared to olivine. This has implications for olivine-pyroxene mixtures and their evolution. E.g. in thecase of asteroid (433) Eros, the variation of the spectral slope is minor, but other spectral parameters show some variation. As
the surface of Eros is old, we hypothesise that spectral slope changes induced by olivine alteration already saturated and theleading source of the spectral variation is pyroxene, which does not show large variations in the slope. In contrast asteroid(25143) Itokawa is younger and thus still shows variations in the spectral slope as it has not saturated yet.

Figure 1. Spectral differences caused by laser and hydrogen ion (H+) irradiation. Each bar connects at the upper end the reflectance, R, ofthe fresh material and at the lower end R of the material weathered to the level marked in the legend.

References[1] Hapke, B. 2001, J. Geophys. Res., 106, 10039[2] Fazio, A., Harries, D., Matthäus, G., et al. 2018, Icarus, 299, 240[3] Sunshine, J. M., Pieters, C. M., & Pratt, S. F. 1990, J. Geophys. Res., 95, 6955
[4] Sunshine, J. M., Pieters, C. M., Pratt, S. F., & McNaron-Brown, K. S. 1999, in Lunar and Planetary Inst. Technical Report,
Vol. 30, Lunar and Planetary Science Conference, 1306

Solid Materials of Mineral and Rock on the Solar System: X-ray Unit and Mixed Status
Yasunori Miura1 and Toshio Kato2
Faculty of Science, Yamaguchi University, Yoshida, Yamaguchi, Yamaguchi, JAPAN
2
Department of Earth System Sciences, Faculty of Science, Yamaguchi University, Yoshida, Yamaguchi, Yamaguchi, JAPAN1

Introduction: Solid materials of all celestial bodies on the Solar System (with technical limits of whole observation andcollection by man-made satellites) should be defined clearly as main purpose of this paper based on academic data of thosesolids from the Earth’s definition relatively.
Academic definition: All mineral crystals on Earth are defined with X-ray determination (as arrangement of 0.1nm unit)
and chemical composition (as stoichiometric compound) with its occurrence on the academic material database (as Earth’s
mineral), where the rock is composed on many mineral crystals or mineral with mixed irregular solids (with light or heavy
elements) usually. This Earth’s definition is easily applied to investigate and determination to unknown samples including
extraterrestrial samples on Earth and visiting collections on the Moon (and Mars and Asteroids etc.). However, basic definitionof solid samples on extraterrestrial sources is not enough to be defined (especially on its developed status as the Celestialbodies) as shown in Table 1.
New concept of the Solar System’s material: Solid bodies of the Solar System have been accepted mainly from their
movements from the geo-centered theory to the Helio-centered theory through many astrophysical investigators based on theMoon and nearest planetary tracking data. Therefore, we should investigate by solid material database (rock and/or mineralcrystal) of each Celestial body. This is main reason why a) mineral spices are completely different with the water-planet Earth(three systems of rock, ocean water and atmosphere as the mineral differentiation) and other Celestial bodies (mainly rockand/or atmosphere systems as different generation of mineral and rock compared with the planet Earth), b) previous collected
extraterrestrial rocks (without chondrules or not) shows different evolution of glass and mineral, c) final mineral grains (soils,
carbonates and silica) of the Earth’s sedimentary process cannot be obtained clearly on extraterrestrial samples so far, and d)various mineral deposits of light element of carbon (from extreme to lower conditions) are obtained from macroscopic tomicroscopically as shown in Table 1.

Existence of fluid-related grains: Carbon-bearing grains show only light element to exist all phase states from solid toliquid to vapor condition with various compositions, texture and atomic structure. Therefore, it is significant indicator to detect
its formed process with or without fluid on water-planet Earth (to form final global carbonate minerals and its rocks) , theMoon (to form global carbon distribution rich in fine regolith soils on surface), Mars (to form global carbon-rich grains anddeposits) and Asteroids (carbon-rich in fine regolith grains and/or carbon-bearing grains and rocks) as shown in Table 2.
Discussion: Earth’s minerals formed as large mineral crystals are defined by atomic structure and chemistry based on Xray analysis and EPMA-ATEM/SEM microanalyses in laboratory on Earth. On the other hand, extraterrestrial samples of theMoon, Mars and Asteroids have no large crystal of mineral grains (due to no global water system on these bodies). Therefore,
Earth’s mineral crystal cannot be obtained at any other planets and Asteroids without the global water system. Remote-sensing
detectors by the IR and Visible wavelengths are mainly instant data obtained from mainly molecular data (atom-atom
distances) which are different with Earth’s mineral definition. This suggests that extraterrestrial mineral rocks (or rockyminerals) are considered to be imperfect solids compared with Earth-type mineral crystal, which means that main X-ray peaksof crystal planes (hkl) are mainly formed during the developed processes with short extreme condition of simple or multiple
impact heating and cooling processes on the extraterrestrial bodies. In short, all celestial bodies at the Solar System arecompletely different on its process and fluid contribution for rocky mineral or mineral rock formation (including the Hayabusa
samples), which means that solid bodies of the Solar System might be the Helio-centered theory-type material rocks which are
not used by the Earth-type mineral rocks to all other extraterrestrial bodies (not as the Earth (geo)-centered materials as used in
the astronomical scale previously).

Summary: The following data are summarized in this study. 1) Solid materials of all Celestial bodies on the Solar
System are discussed on the solid data from the Earth’s definition relatively to the extraterrestrial Celestial bodies. 2) All
mineral crystals on Earth are defined with X-ray determination and chemical composition with its occurrence on the material
database, though basic definition of extraterrestrial sample is not enough to be defined from less crystalline rocks. 3) The
Earth’s minerals show absolutely huge numbers of mineral species, well differentiated minerals, various Earth’s sedimentary
process, and various mineral deposits of carbon-bearing grains. 4) Carbon-bearing grains show various grains, texture andcompounds which are indicators of the detailed formation process on each Celestial body including the Hayabusa samples. 5)
The material data of the samples might indicate that all material data of mineral and rock are different from the Celestialbodies of the Solar System.
References:
Cresswell R., Beukens R., Rucklidge J. and Miura Y., Distinguishing spallogenic from non-spallogenic carbon in chondrites
using gas and temperature separations. Nuclear Intruments and Methods in Physics Research Section B (NIM-B) (Elsevier
Science, North-Holland), 92, 505-509, 1994.
Kato T. and Miura Y., The crystal structures of Jarosite and svanbergite. Mineralogical Journal, 8, 419-430, 1977.
Miura Y., Comparative consideration of Earth’s mineral from three major events: Solid formation of other Celestial bodies,
JAMS-2021 (Hiroshima Univ.), R5-01, 2021.
Miura Y., Carbon and carbon dioxides gas fixing by dynamic processes, Publication of JP5958889B2 (Active to 2028), 2016.
Miura Y., Complex texture and structure of shocked quartz mineral with graphite grain., Acta Crsyt., 64, 55, 2008.
Miura Y. , Material evidence for compositional change of dusts by collision applied to the Solar System's formation and theAsteroid belt. The ASP Conf. Series, 63, 286-288, 1994.
Miura Y. and Kato T., Shock waves in cosmic space and planetary materials. American Institute of Physics (AIP) Conf. Proc.,
283 (Earth and Space Science Information Systems), 488-492, 1993.
Miura Y., Accelerator mass spectrometry facilities in Japan. The Future of AMS Requirements in Canada (NSERC), 1, 45,
1991.
Miura Y. and Tomisaka T., Composition and structural substitution of meteoritic plagioclases. Mem. Natl Inst. Polar Res.,
Spec. Issue (NIPR, Tokyo), 35, 210-225,1984.
Miura Y., Computer simulation of anomalous composition of Mg-Fe plagioclase in meteorite. Mem. Natl Inst. Polar Res.,
Spec. Issue (NIPR, Tokyo), 35, 226-242, 1984.
Smith D.G.W., Miura Y. and Launspach S., Fe, Ni and Co variations in the metals of some Antarctic chondrites. Earth andPlanetary Science Letters, 120, 487-498, 1993.

Model of Material Characteristics of Carbonaceous Meteorites from Texture of Carbon-Bearing
GrainsYasunori Miura
Faculty of Science, Yamaguchi University, Yoshida, Yamaguchi, Yamaguchi, JAPANIntroduction: Carbonaceous meteorites are unique meteorites in the extraterrestrial rocks. In this study author reports
proposed model of previous unknown characteristics of hard samples with voids, carbon-bearing texture, Ca-Al-rich grains(with H, C, S) and detailed model of carbon-bearing grains in the carbonaceous meteorite which are applied to the Hayabusa
samples as the present purpose here.
Characteristics of Carbonaceous chondrite: Carbonaceous chondrites contain ususally Ca and C elements (with Mg, Na
ions and H2O molecules), where these ions can form molecular gel (polymer) and amorphous (poorly crystallized Emblyo-typeof carbonates (calcite and aragonite in mineral crystal). This suggests that extraterestial Celestial body is started as 1)
Ordinary chondrite-type micrograins and intercluster pores (as less 2nm) followed gel pores (2 to 20nm in size) withoutcarbonated calcium silicate matrixes, and 2) Carbonaceous chondrite-type micrograins show Ca-modified silica gel clusters
mixed with amorphous calcium carbonates (ACC) with pores (4 to 10nm) as shown in Table 1. This model can be explain
why the meteorite shows porous rocks and harder rock (than normal porous crystalline rocks with light weight). These gel toamorphous grain can be formed in present laboratory and industrial application as Ca-Al-rich grains (with H, C, S) as low
carbon binders. This is just by accident in natural meteorite field academically because author has been investigated carbon
origin and its application in science filed (including the AMS carbon dating projects) used in terrestrial age of the Antarctic
meteorites (also in the Apollo samples as its carbon origins), and recent project of carbon and carbon dioxides gas fixing by
dynamic processes (as the public University project). If it can be confirmed in science filed, then we can apply thatcarbonceous meteorites (and Moon rocks) has similar texture to fix carbon (or carbon dioxides) by its sources anddevelopment of its extraterrestrial rocks (model of grains of ions-gel polymer-amorphouse calcium carbonates as shown in
Table 1, followed clear calcite crystal as in water planet Earth finally). This can be applied it also to decrease the climate
warning scientifically and inductrially (as well-known Japanese scientist indicated by calculated estimates from global
environmental data). The paper is dicussed it as material data with proposed model in the Hayabusa Symposium in Tokyo.

Summary: Author proposes model of hard samples with voids, carbon-bearing texture, Ca-Al-rich grains (with H, C, S)
and carbon-bearing grains in the carbonaceous meteorite (also including the Hayabusa samples).
References:
Miura Y., Comparative consideration of Earth’s mineral from three major events: Solid formation of other Celestial bodies,
JAMS-2021 (Hiroshima Univ.), R5-01, 2021.
Miura Y., Carbon and carbon dioxides gas fixing by dynamic processes, Publication of JP5958889B2 (Active to 2028), 2016.
MiuraY. and Tanosaki T., Characterization of products from the nuclear and fire-electric facilities (in Japanese), University
Report (Yamaguchi, Japan), 1-64, 2009.
Miura Y. , Material evidence for compositional change of dusts by collision applied to the Solar System's formation and theAsteroid belt. The ASP Conf. Series, 63, 286-288, 1994.
Miura Y. and Kato T., Shock waves in cosmic space and planetary materials. American Institute of Physics (AIP) Conf. Proc.,
283 (Earth and Space Science Information Systems), 488-492, 1993.
Smith D.G.W., Miura Y. and Launspach S., Fe, Ni and Co variations in the metals of some Antarctic chondrites. Earth andPlanetary Science Letters, 120, 487-498, 1993.
Miura Y., Computer simulation of anomalous composition of Mg-Fe plagioclase in meteorite. Mem. Natl Inst. Polar Res.,
Spec. Issue (NIPR, Tokyo), 35, 210-242, 1984.

Neural network for classification of asteroid spectraDavid Korda1 , Antti Penttilä2 , Arto Klami3 , and Tomáš Kohout1,4
1

Department of Geosciences and Geography, University of Helsinki, Finland2
Department of Physics, University of Helsinki, Finland3
Department of Computer Science, University of Helsinki, Finland
4
Institute of Geology, Czech Academy of Sciences, Czech Republic

Introduction
Asteroid mineral composition is important parameter in planetary science, planetary
defence, and in-space resource utilisation. Currently-used methods provide us mainly
quantitative information about the asteroid composition. The methods are based on
empirical relations between spectral parameters (band areas, positions, depths), or on
spectral unmixing, and are highly sensitive to quality and consistency of input reflectancespectra. We test artificial neural networks as a tool which can infer mineral composition
directly from the reflectance values.

Methods
Artificial neural networks are used in tasks which are very difficult to define with exact
mathematics. A sensitivity of the networks to quality of input data (e.g., absolutereflectance values or variations in spectral slope) can be partially suppressed. The
networks are made of layers of neurons. Each neuron in a layer is non-linearly connectedwith neurons in the previous and following layers. The non-linearity and complexity ofneural network enable them to solve various tasks.
We use neural network for computing of mineral composition of the most common
silicates presented in meteorites (olivine, orthopyroxene, clinopyroxene, and plagioclase).
Our neural network composed of the input layer with reflectance values, one ‘intermediate’layer (hidden layer), and the output layer. The outputs are modal composition of theminerals and their chemical composition represented with end-members.

Data
We utilised measured reflectance spectra from the Relab database1 . We are motivated by
the ASPECT instrument (part of Hera/Milany CubSat) which will carry-out observations
in visible and near-infrared part of spectra. For this reason, we chose spectra which coverinterval between 350 nm and 2550 nm with the resolution 15 nm or better.

Results
Olivine and orthopyroxene are the most common minerals in ordinary chondrites. Therefore, we firstly applied the neural network on a set of olivine and pyroxene spectra.
1

http://www.planetary.brown.edu/relabdata/

1

Figure 1: Results of chemical composition. Top row: olivine. Bottom row: pyroxene.
The neural network contained only one hidden layer with 30 neurons. The outputs
were volume fractions of the minerals and their chemical composition. We trained the
network on about 80% of the whole dataset and used the remaining 20% to test theaccuracy of the predictions. The results obtained from the 20% are shown in Fig. 1.
The vertical axes show the correct (previously published) values while the horizontal
axes the values predicted by the neural network. In the top row, there are iron andmagnesium composition in olivine. In the bottom row, there are iron, magnesium, andcalcium composition in pyroxene.

Discussion
Except a few outlier, the predicted composition is usually within about 10% from theactual composition. The outliers might be a consequence of a limited training dataset or
ambiguously determined actual composition. In the near future, the predictive capabilityof the network will be improved via optimisation of its architecture and due to increase
number of training samples. In the next step, we will train the network on synthetic
spectra of olivine, orthopyroxene, and plagioclase and evaluate the network on real
ordinary chondrites.

2

Assessment of organic, inorganic and microbial contamination in the facilities of theExtraterrestrial Sample Curation Center of JAXA
*Yuya Hitomi1, Toru Yada2, Aiko Nakato2, Miwa Yoshitake1,3, Kana Nagashima2, Haruna Sugahara2, Shino Suzuki2, Masahiro
Nishimura2, Kazuya Kumagai1, Masanao Abe2, Tatsuaki Okada2, Shogo Tachibana2,4, and Tomohiro Usui2
1
Marine Works Japan Ltd., Yokosuka, Kanagawa 237-0063, Japan, 2Institute of Space and Astronautical Science (ISAS),
Japan Aerospace Exploration Agency, Sagamihara, Kanagawa 252-5210 Japan, 3 Japan Patent Office, Chiyoda-ku, Tokyo
100-8915, Japan, 4UTOPS, Grad. Sch. Sci., Univ. Tokyo, Tokyo 113-0033, Japan.
The Extraterrestrial Sample Curation Center of JAXA (ESCuC) have received samples from S-type near-Earth asteroid
25143 Itokawa returned by Hayabusa and C-type near-Earth asteroid 162173 Ryugu by Hayabusa2 [1, 2]. The samples havebeen taken out from sample containers, investigated in a non-destruvtive way, and stored in high vacuum and purified nitrogen
circulating clean chambers installed in ISO Class 6 clean rooms in the ESCuC. A series of cleaning procedures for tools, jigs,
and sample storage/transport containers has been established for the usage in the clean chambers to avoid potential
contamination of samples [3].
Along with the contamination control, it is also important to keep monitoring the cleanliness of clean rooms and cleanchambers. For instance, several biotic amino acids were once detected from contamination coupons set inside the cleanchamber for Itokawa grains [4], of which contamination level was similar to that reported at the curation facility at NASA
Johnson Space Center [5, 6]. In recent years, contamination of organics has been assessed regularly through exposure ofwafers for 15-20 hours in the clean rooms and clean chambers. The regular assessment has found that the clean rooms is kept
at the ISO-SCC Class -8 level and the clean chambers at the ISO-SCC Class -9 for organics. Regular contamination assessmentof metallic elements has shown that both clean rooms and clean chambers maintain the level of ISO-SCC Class -10 or higher
for all measured elements although elements contained in equipments and tools, such as Fe, Cu, Ni, Cr, Al, Zn, Mn, and Co,
were often detected at a higher level in the clean chambers than in the cleanrooms. The contamination levels of Na and K, bothof which are good indicators of contamination from human beings, are low enough to be at the ISO-SCC class -11 level forboth clean chambers and cleanrooms. In addition to organic and inorganic monitoring, assessment of microbial contaminationlevel is scheduled for the cleanrooms and clean chambers in this fiscal year.
References[1] Yada T. et al. (2014) Meteoritics Planet. Sci. 49, 135-153. [2] Yada, T. et al. (2021) LPSC 52, #2008. [3] Yoshitake M. etal. (2021) JAXA-RR-20-004E, 1-30. [4] Sugahara H. et al. (2018) Earth Planets Space 70, 194. [5] Dworkin et al. (2018)OSIRIS-REx contamination control strategy and implementation. Space Sci Rev 214:9. [6] McLain et al. (2015)
Contamination Knowledge Report JSC Curation Cabinets, personal communication.