Guidebook for application for the Ryugu Reference ProjectMeasurement Definition Team (RRP-MDT)
June 6, 2024

Key milestones for the applications for Ryugu Reference Project Measurement
Definition Team (RRP-MDT)- Call for applications: June 6, 2024
- Submission of application due: July 5, 2024
- Decision announcement: No earlier than July, 2024 (TBD)- Expected completion of tasks: ~6 months after selections

1. Introduction
The Hayabusa 2 mission returned ~5.4 g of sample from the C-type asteroid Ryugu.
The sample was stored in a sealed container during cruise and recovery operations until
finally transported to the Hayabusa 2 clean chamber in the Institute of Space andAstronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA) clean room
facility (Tachibana et al., 2020). JAXA's Phase 1 curation team processed the sample
following the protocols described in Yada et al. (2021, 2023) and distributed fractions tothe Hayabusa 2 initial analysis team, Phase 2 curation teams and researchers selected
through the Announcement of Opportunity for Hayabusa 2 Samples(https://curation.isas.jaxa.jp/ryuguao_accepted_proposals). The curation and initial
analysis teams showed that the returned sample represents the surface of Ryugu andpossesses similarity to the Ivuna-type (CI) chondrites in terms of petrology, mineralogy,and inorganic/organic chemistry (e.g., Ito et al., 2022; Nakamura E. et al., 2022;
Nakamura T. et al., 2023; Naraoka et al. 2023; Noguchi et al. 2022; Yabuta et al. 2023;
Okazaki et al. 2023; Pilorget et al. 2022; Yokoyama et al., 2023a). Further, the migrationand evolution of Ryugu's parent body have also been reconstructed based on the analysesof Ryugu particles.
The similarity to the CI-chondrites has the potential to significantly increase thescientific value of the Ryugu sample because the CI-chondrites best represent thechemical compositions of non-volatile in the Solar System (e.g., Lodders, 2021). The
chemical compositions of CI-chondrites provide a reference for Solar Systemcompositions and are widely used in geochemistry. However, these meteorites havesuffered from terrestrial alteration, which has modified their original chemistry,
particularly for the volatile elements. In contrast, the Ryugu sample has experienced
minimal terrestrial alteration, making it a unique and valuable resource for research,
although the sample amount available for research is limited.
1The Ryugu sample could potentially serve as another reference for Solar Systemcompositions, supplementary to the CI-chondrite-derived reference. However, one should
reassess the potential of the Ryugu sample as a new reference. JAXA previously received
a voluntary report from the community, with a preliminary investigation of the feasibility
and merit of using the Ryugu sample for the reference (Yokoyama et al. submitted). The
investigation showed that the Ryugu sample’s heterogeneity yielded a variation inelemental and isotopic compositions among the individual small fractions (typically <20mg) (See also Nakamura E. et al., 2022; Nakamura T. et al., 2023; Yokoyama et al., 2023a,2023b). Furthermore, these fractions were insufficient to analyze some isotopes (e.g., Ru,W), resulting in the absence of these isotopic compositions in the Ryugu data sets.
To this end, JAXA invites individuals to apply for membership in a new science team− the Ryugu Reference Project Measurement Definition Team (RRP-MDT). RRP-MDTwill work on the tasks briefly outlined below:
1) Define the scientific goals and objectives of the Ryugu Reference Project (e.g., listof elements, isotopes, and chemical species in the Ryugu Reference; accuracy andprecision required for the Ryugu Reference),2) Recommend the analytical protocols that meet the project requirements (e.g.,amount of Ryugu sample, means for producing an uncontaminated powder,instrumentation, and number of analytical runs, etc.),3) Develop an MDT final report that will be provided to JAXA for publication as acommunity white paper.
Based on the MDT report, JAXA will evaluate the significance and scientific merit ofproceeding with Ryugu Reference Project.
To respond to this RRP-MDT solicitation, please send a letter of application by July
5, 2024, following the guidelines below. A Q&A session for potential applicants is heldon Mid-June, 2024. Please also visit the RRP-MDT website for more information.
2. Expected Processes
2.1 Selection and activity period
The RRP-MDT shall comprise approximately ~15 members tasked with theabovementioned responsibilities. The panel appointed by the Hayabusa 2 sample
allocation committee (HSAC) will select the RRP-MDT members based on an open,international, competitive call. The chair will be selected from the RRP-MDT members.
The expertise being sought is in geochemistry and cosmochemistry. Additionally, wewelcome experts in mineralogy, petrology, planetary physics, astronomy, solar systemformation, statistics, and related fields. Early career researchers are encouraged to apply.
It is anticipated that the study and subsequent report will take approximately 6 months,
that RRP-MDT activities will take place via video conferencing, and that no in-person
meetings will be planned.
2.2 Application process
Applicants are required to submit an applications by email (jaxa-curation-rrp@jaxa.jp)
before the deadline of July 5, 2024 at 12:00 (JST). Applications for the RRP-MDT require2

the submission of an application form (details in Section 2.2.1 and 2.2.2) and a current
CV. Once the evaluation processes are completed, all applicants will be notified of theresults.
2.2.1 Application documents
The application forms must be written in English and submitted in PDF format. Theminimum font size for the main text shall be 11 points, and the text shall be singlespaced. Text within figures and tables may use a smaller font as long as it is legible.
The forms must be on A4/US letter-size paper and not exceed three pages (includingfigures). The template of the application forms will be available on the RRP website(https://curation.isas.jaxa.jp/rrp/rrp-mdt_application_templete.doc). Any form of CV
is acceptable.
2.2.2 Elements required in the application forms
The application forms should state:1) the reasons for your interest in this opportunity,2) the specific experience/expertise/capability that you could contribute thatwould be most relevant to the success of the RRP-MDT,3) any analytical methodologies or modern laboratory instrumentation with which
you have expertise.
2.3 Application review and selection
2.3.1 Panel review
Following the deadline for the submission of applications, the RRP-MDT selection
panel shall convene to review the applications. The panel will consist of approximately
five scientists with broad expertise in the field of cosmochemistry, including chemistry,mineralogy, petrology, volatiles, and organics.
2.3.2 Notification of selection results
The selected applicants will be informed via email, and a list of RRP-MDT will be
published on the RRP website.
3 General conditions and Confidentiality- This Call for Applications is open only to individuals. Group applications will not beconsidered. Additionally, collaborations and teams will not be considered.
- The issuance of this Call for Applications does not obligate JAXA to accept any of
the applications. Any costs incurred by an applicant in preparing a submission in
response to this Call are the responsibility of the applicant.
- Meetings will be conducted via teleconference. It is the responsibility of theindividual's funding institution to provide honoraria and per diem for participation inmeetings.
- The selected applicant shall comply with the obligation to maintain theconfidentiality of the data, knowledge, and information communicated in theframework of the activity.
References
Ito M. et al. (2022) Nature Astronomy DOI: 10.1038/s41550-022-01745-5
Lodders K. (2021) Space Sci. Rev. DOI: 10.1007/s11214-021-00825-8
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Nakamura E. et al. (2022) Proc. Japan Academy, Ser. B DOI: 10.2183/pjab.98.015
Nakamura T. et al. (2023) Science DOI: 10.1126/science.abn8671
Naraoka et al (2023) Science DOI: 10.1126/science.abn9033
Noguchi et al (2022) Nature Astronomy DOI: 10.1038/s41550-022-01841-6
Okazaki et al. (2023) Science DOI: 10.1126/science.abo0431
Pilorget et al. (2022) Nature Astronomy DOI: 10.1038/s41550-021-01549-z
Tachibana S. et al. (2022) Science DOI: 10.1126/science.abj8624.
Yabuta et al. (2023) Science DOI: 10.1126/science.abn9057
Yada T. et al. (2021) Nature Astronomy DOI: 10.1038/s41550-021-01550-6
Yada T. et al. (2023) Earth Planets Space DOI: 10.1186/s40623-023-01924-2
Yokoyama T. et al. (2023a) Science DOI: 10.1126/science.abn7850
Yokoyama T. et al. (2023b) Science Advances DOI: 10.1126/sciadv.adi7048
Yokoyama T. et al. (2024) submitted to Geochem J. (https://arxiv.org/abs/2405.04500)

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