Asteroid explorer, Hayabusa2,press conferenceDecember 6, 2018
JAXA Hayabusa2 ProjectTopics
E Report on the current status of Hayabusa2
E Q & A and discussion
E Tour of the control room

HPlease understand that only people who applied in advance can join the tour)Contents
0. Hayabusa2 and mission flow outline
1. Current status and overall schedule of the project
2. Solar conjunction operation report
3. Image release
4. Other
5. Future plans

Overview of Hayabusa2
ObjectiveWe will explore and sample the C-type asteroid Ryugu, which is a more primitive
type than the S-type asteroid Itokawa that Hayabusa explored, and elucidate
interactions between minerals, water, and organic matter in the primitive solarsystem. By doing so, we will learn about the origin and evolution of Earth, theoceans, and life, and maintain and develop the technologies for deep-space return
exploration (as demonstrated with Hayabusa), a field in which Japan leads theworld.

Expected results and effects
GBy exploring a C-type asteroid, which is rich in water and organic materials, wewill clarify interactions between the building blocks of Earth and the evolution of
its oceans and life, thereby developing solar system science.
G Japan will further its worldwide lead in this field by taking on the new challenge ofobtaining samples from a crater produced by an impacting device.
GWe will establish stable technologies for return exploration of solar-system bodies.

Features:
GWorld’s first sample return mission to a C-type asteroid.
GWorld’s first attempt at a rendezvous with an asteroid and performance ofobservation before and after projectile impact from an impactor.
GComparison with results from Hayabusa will allow deeper understanding of thedistribution, origins, and evolution of materials in the solar system.

International positioningK
GJapan is a leader in the field of primitive body exploration, and visiting a type-C
asteroid marks a new accomplishment.
GThis mission builds on the originality and successes of the Hayabusa mission. In
addition to developing planetary science and solar system exploration
technologies in Japan, this mission develops new frontiers in exploration ofprimitive heavenly bodies.
GNASA too is conducting an asteroid sample return mission, OSIRIS-REx (launch:2016; asteroid arrival: 2018; Earth return: 2023). We will exchange samples andotherwise promote scientific exchange, and expect further scientific findings
through comparison and investigation of the results from both missions.

(Illustration: Akihiro Ikeshita)
Hayabusa 2 primary specifications
MassApprox. 609 kg
Launch3 Dec 2014
MissionAsteroid return
Arrival27 June 2018
Earth return2020
Stay at asteroid
Approx. 18 months
Target body
Near-Earth asteroid Ryugu
Primary instruments
Sampling mechanism, re-entry capsule, optical cameras, laser range-finder,
scientific observation equipment (near-infrared, thermal infrared), impactor,miniature rovers.

Mission Flow
Launch3 Dec 2014

Arrival at asteroid
June 27, 2018E▲
Earth swing-by
3 Dec 2015

Examine the asteroid by remote sensing
observations. Next, release a small lander androver and also obtain samples from the surface.

Earth returnlate 2020

Depart asteroid
Nov–Dec 2019

Create artificial
craterSample analysis(Illustrations: Akihiro Ikeshita)

After confirming safety, touchdown
within the crater and obtain
subsurface samples

Release impactor

Use an impactor to create
an artificial crater on theasteroid’s surface1. Current project status& schedule overview

Current statusK
– On November 23, a C'89.:*<287was performed and the spacecraft started
moving at a speed of about 12 cm/s in the direction away from Ryugu.
– From here, Hayabusa2 will reach a distance of 100km from Ryugu and return tothe home position at the end of December.
– The HJST (Hayabusa2 Joint Science Team) international science conference
was held on December 3 – 4.

Schedule overview:
2015
12

Event	3

72<2*589.:*<287

2016
10 12'launch	., 2017

4
8=:7.A<8*;<.:82-;?270+A

*:

*A

2020
12

Arrival at Ryugu	=7. #..7<12:A
*:<1:.<=:7;<.:82-9:8@262<A89.:*<287;

Earth swing-by	., *: =72019

6 7

*99:8*,1$H  (I<.;<89.:*<287; Southern hemisphere station
operations (CAN/MLG)	
 *A  ",<*A

Ion engine operations ※	

2018

Departure from Ryugu	!8>L.,

Capsule re-entry	
*<.


Optical navigation	 Solar conjunction	
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!8>

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2. Conjunction Operation Report
E On November 18, preparations for the solar conjunction began. A attitude
rotation of 180 degrees was then performed in anticipation of the reversalof the relative positions between the Sun, Earth and asteroid, which will
mirror the configuration before conjunction.
E On November 23, the spacecraft was placed into the conjunction
transition orbit (COI: Conjunction Orbit Insertion), and started moving atabout 12 cm/s in the direction away from Ryugu (towards the Sun).
E The trajectory of the spacecraft was accurately estimated and the firsttrajectory correction maneuver (TCM 1) was made on November 30.
E Currently, the angle between the Sun-Earth-spacecraft is less than 3degrees, so communication with Hayabusa2 is difficult.
E A second trajectory correction maneuver is planned for December 25 andΔVHHPRKHome Position RecoveryIoperation on December 29 to returnthe spacecraft to the home position.
2. Conjunction Operation ReportOrbit and trajectory control operation
Orbit controlNameDateCOI

2018/11/23

TCM1

2018/11/30

TCM22018/12/25

HPR

2018/12/29

Sun

12/15
12/10

COI : Conjunction Orbit Insertion
EEEEE
TCM : Trajectory Correction ManeuverEEEE
HPR : Home Position Recovery
EEEEE

H©JAXAI

12/5

12/25

12/20

TCM2

TCM1

11/30

11/23

COI

Ryugu

HPR

12/29

Conjunction transition orbit in the Hill coordinate system3. Image release
Summary of the following images:
E Movie of the surface of Ryugu using the small monitor
camera (CAM-H).
EEEEDFull version of previously published video.

E Separation of target markers and subsequent tracking movie.
E High resolution image captured close to the touchdown
candidate site. 3. Image releaseMovie of the surface of Ryugu by the small monitor camera (CAM-H)
Hmovie
20 x speedI
Sequential images taken with the small monitor camera (CAM-H) during Touchdown 1 Rehearsal 3 (TD1-R3). The images
were captured just after the spacecraft began to ascend at 11:47 JST on October 25, 2018 (altitude of about 21m). The rising
speed is about 52 cm/s. The last image is at 11:53 JST at an altitude of about 200m. The images in the first and the last parts
have a 5 second interval, while the others were captured ever second. HImage creditKJAXAI3. Image releaseSeparation of target markers and subsequent tracking video

Hmovie 40x speedI

Tracking the target marker after release during Touchdown 1 Rehearsal 3 (TD 1-R3). The images werecaptured from October 25, 2018 at 11:38 to 11:48 JST. The altitude is about 12m at the beginning of themovie and 56m at the end. (Image credit: JAXA).



H#I,<=*59:80:.;;8/% # 89.:*<287
AltitudeReturn to home position
Home position

EEE20km

Target marker
separation
Deceleration ΔV

GCP-NAV (Ground Control Point Navigation)
EE→Method of determining the position andspeed of the spacecraft by observing
characteristic points on the asteroid
surface.

HPNAV (Home Position Navigation)
EE→Method of determining the position andspeed of the spacecraft from direction ofLowest altitude 12m the center of the asteroid image andattitude of the probe.
Increase ΔV5km
~40m

Time(JST)

©JAXA

10/24~13:0010/124~23:00Target marker deployed10/25 11:37Falt. 13m

10/26

HREFITD1-­‐R3	  low	  al�tude	  sequence
Descent at
10cm/s while
using LIDAR.

After tracking TM,ascend and returnto 20km altitude.

LIDAR altitude measurement

Begin LRF altitudecontrol from ~25m
altitude.

Lateral thruster
injection tosynchronize withasteroid rotation
speed.

Descend a few meters
while pushing TM
towards surface toseparate.TMseparation

Maintain ~20m
altitude while
tracking TM withcamera

25m

20m
FLASH
useRegion imaged byONC-W1
TM track0m

H©JAXAIIn this operation:E The exact ability of landing accuracy (ground guidance accuracy) was found (= 15.4m).
E Implemented the possibility of landing using a target marker as a reference pointJ

3. Image releaseSeparation of target markers and subsequent tracking video

Hmovie 10x speedI

Tracking the target marker after release during Touchdown 1 Rehearsal 3 (TD 1-R3). Theimages were captured from October 25, 2018 at 11:38 to 11:48 JST. The altitude is about
12m at the beginning of the movie and 56m at the end. (Image credit: JAXA).



3. Image releaseHigh resolution image near the touchdown candidate siteComposite of images taken near the touchdown candidate site

HImage creditKJAXA, University of Tokyo, Kochi University, Rikkyo University, Nagoya University,Chiba Institute of Technology, Meiji University, University of Aizu, AIST.)

HREFIITouchdown candidate site: L08-B
HPreviously published imagesI

H6*0.,:.-2<K)&72>.:;2<A8/%84A88,12&72>.:;2<A#244A8&72>.:;2<A!*08A*&72>.:;2<A12+*7;<2<=<.
8/%.,178580A .232&72>.:;2<A&72>.:;2<A8/2B=$%I4. Other
■HJSTHHayabusa2 Joint Science TeamI Meeting
E On December, 3 – 4, an international science meeting was heldto discuss future operations and the scientific results so far.

■Place names on Ryugu
H©JAXAIE We are currently awaiting the results from the IAU(International Astronomical UnionIWorking Group forPlanetary System Nomenclature.
4. Other
■OSIRIS-REx
E Arrived at Bennu on December 3 (US time)
HmovieI

This series of images taken by the OSIRISREx spacecraft shows Bennu in one fullrotation from a distance of around 50 miles(80 km). The spacecraft’s PolyCam camera
obtained the 36 2.2-millisecond frames
over a period of four hours and 18 minutes.
Credit: NASA/Goddard/University ofArizona
Ryugu

Bennu

6*0. ,:.-2<K) &72>.:;2<A 8/ %84A8 8,12 &72>.:;2<A #244A8 &72>.:;2<A !*08A* &72>.:;2<A12+*7;<2<=<.8/%.,178580A .232&72>.:;2<A&72>.:;2<A8/2B=$%

Credit: NASA/Goddard/University of Arizona

distance20km	

distance6km	

distance 80km	 HREFIILocation of Ryugu & Bennu

EarthBennu

Ryugu

H©JAXAI4. Other
■Joint session with OSIRIS-Rex at the AGU Fall Meeting
E AGU = American Geophysical UnionHlarge planetaryscience society in the USA)E Fall Meeting : December 10 – 14, 2018, Washington DC
E Session nameKA First Look at 162173 Ryugu and 101955
Bennu: Hayabusa 2 and OSIRIS-REx Arrive at Their
Respective Target Asteroids
E Session date: December 11 (oral), December 12 (poster).

5. Future plans■Scheduled operations
E Until the end of DecemberEK Conjunction operations
E From January 2019KNormal operations■Announcement of winners for the Ryugu Imagination
ContestE Scheduled late December.
■Press briefing and media
E December 13 (Thursday)E15:30Ereporter briefing @Ochanomizu
Reference materialSmall Monitor Camera HCAM−HII
E Camera built & mounted from donation funds.
E View down sampler horn.

H©JAXAI

Target marker

E Size of body (ball): about 10cm
E Retroreflective film
E 4 barsKrolling prevention
E Inside contains many polyimide globules

A

B

CDE

E First to separateKB
E Sequence of separation: B→A→E→C→D
E On the inside of the target marker is asheet on which is written the names ofmembers from the general public. 

H©JAXAIConjunction operation
E “Conjunction” for spacecraft

2018.12.31

operation refers to the case where
the spacecraft is in the directionthat almost directly overlaps with
the Sun when viewed from Earth.

2018.11.20

Earth

E The alignment means that

communication with thespacecraft is not secure due toradiowaves radiated by the Sun.

SunE In this period, critical operation isnot carried out.

E For Hayabusa2, the duration ofthis period is from late November
2018 – end of December.

Ryugu
Positions of Ryugu and the Earth©JAXA

Conjunction operation
Orbit and trajectory control during the operation
Orbit controlName

Date

COI

2018/11/23

TCM1

2018/11/30

TCM2

2018/12/25

HPR

2018/12/29

Due to the influence from solar tidal forces,
asteroid gravity and solar light pressure, thetrajectory forms a complex shape.

COI : Conjunction Orbit Insertion
EEEEE
TCM : Trajectory Correction Maneuver
EEEEE
HPR : Home Position Recovery
EEEEE©JAXA

Transition orbit during solar conjunction in thehome position coordinate system