Asteroid explorer, Hayabusa2,reporter briefing

November 12, 2019
JAXA Hayabusa2 ProjectTopicsRegarding Hayabusa2,
Departing Ryugu

2019/11/12

Hayabusa2 reporter briefing

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Contents
0. Hayabusa2 and mission flow outline
1. Current status and overall schedule of the project
2. Details regarding the departure from Ryugu
3. Outreach for Ryugu
4. Future plans
Note
In the material distributed during the reporter briefing, the time for departurefrom Ryugu was written as 10:00. However, we have modified the time to 10:05
in this copy, as this is the final time decided.
2019/11/12

Hayabusa2 reporter briefing

3Overview of Hayabusa2
Objective
We 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 theprimitive solar system. By doing so, we will learn about the origin and evolution of Earth, the oceans, and life, andmaintain and develop the technologies for deep-space return exploration (as demonstrated with Hayabusa), a field
in which Japan leads the world.
Expected results and effects
By exploring a C-type asteroid, which is rich in water and organic materials, we will clarify interactions between
the building blocks of Earth and the evolution of its oceans and life, thereby developing solar system science.
 Japan will further its worldwide lead in this field by taking on the new challenge of obtaining samples from acrater produced by an impacting device.
We will establish stable technologies for return exploration of solar-system bodies.
Features:World’s first sample return mission to a C-type asteroid.
World’s first attempt at a rendezvous with an asteroid and performance of observation before and after projectile
impact from an impactor.
Comparison with results from Hayabusa will allow deeper understanding of the distribution, origins, andevolution of materials in the solar system.
International positioningJapan is a leader in the field of primitive body exploration, and visiting a type-C asteroid marks a newaccomplishment.
This mission builds on the originality and successes of the Hayabusa mission. In addition to developing planetaryscience and solar system exploration technologies in Japan, this mission develops new frontiers in exploration ofprimitive heavenly bodies.
NASA too is conducting an asteroid sample return mission, OSIRIS-REx (launch: 2016; asteroid arrival: 2018;
Earth return: 2023). We will exchange samples and otherwise promote scientific exchange, and expect further
scientific findings through comparison and investigation of the results from both missions.

2019/11/12

Hayabusa2 reporter briefing

Hayabusa 2 primary specifications(Illustration: Akihiro Ikeshita)
MassApprox. 609 kgLaunch
3 Dec 2014
MissionAsteroid returnArrival
27 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.

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(image credit: illustrations including spacecraftby Akihiro Ikeshita, others by JAXA)

LaunchDec 3, 2014

Mission flow

Earth swing-by
Dec 3, 2015

Ryugu arrival

MINERVA-II-1 separation

June 27, 2018

Sep 21, 2018

MASCOT
separation
Oct 3, 2018

Ryugu
departure
Earth return
End of 20202019/11/12

Scheduled: MINERVA-II-2 2nd touchdown Impactor (SCI)
Nov 13, 2019
separation
5 April, 2019
July 11, 2019
Oct 3, 2019
completed →Hayabusa2 reporter briefing

1st touchdown
Feb 22, 20195

1. Current project status & schedule overview
Currentstatus8

Scheduleoverview
Event– BOX-C operation was conducted from October 19 and completed as scheduled on
October 30.
– Final confirmation and preparations are underway for departure from Ryugu.
– The scientific meeting “Asteroid Science in the Age of Hayabusa2 and OSIRIS-REx”
was held in Tuscon, USA and with many members of the Hayabusa2 project participating.
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2. Departure from Ryugu•

Ryugu departureNovember, 13 at 10:05 JSTplanned
At this time, the “Near Asteroid Operation Phase” will shift to the “Return Phase”.

•The prerequisites for departure, namely (1) that there are no problems with the scientific resultsand (2) preparations for departure are complete were confirmed by the project.

•From the home position, the spacecraft will start to move away from the asteroid at a speed ofabout 10 cm/s using the RCS thrusters.

•Images of Ryugu moving away will be captured for about 5 days (“Ryugu FarewellObservation”). After that, Ryugu will not be visible due to a change in spacecraft attitude.

•After a trial run for the ion engines from November 19  December 2, the ion engine cruise
operation will begin after December 3.

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Hayabusa2 reporter briefing7

2. Departure from Ryugu
cee
er en
ph flull s in
Hi i t yu av ug gr km
Ry of 65e nga
R

Earth direction
Sun direction

Final observations ofRyugu conducted
mainly by the ONC-T

Ryugu

Thruster injection tobegin departurefrom Ryugu

HP

11/1311/18
Ryugu Farewell
Observation

After 12/3
Return Phase ion
engine cruise started

Confirmation and adjustment of ion
engine performance. Return toEarth-orientated attitude for highspeed data downlink

ONC

11/13
20km
2019/11/12

11/15
35km

11/17
11/1811/19
50km Change in attitude forion engine operation
Hayabusa2 reporter briefing

11/2012/2
Ion engine test
run period
8Hayabusa2 Mission Success Criteria
Mission goal

Minimum success

Full success

Extra successScience goal
Investigate the material sciencecharacteristics of C-type asteroids. In
particular, clarify the interaction
between minerals, water and organicmatter.

Provide new insights on thesurface material of C-type
asteroids by observations in thevicinity of the asteroid.

Obtain new findings on mineralwater-organic interactions from theinitial analysis of the collectedsamples.

Integrate astronomical & microscale
information to create new scientificresults regarding materials for Earth,sea and life.

Science goal
Investigate the formation process ofasteroids by direct exploration of theasteroid’s reaccumulation process,internal structure and subsurface
material.

Provide insights on the internal
structure of the asteroid byobservations in the vicinity of theasteroid.

Obtain new knowledge on the internal
structure and subsurface material of
the asteroid by observing thephenomena caused by collisions withan impacting body.

Present scientific results on asteroid
formation based on new findings
regarding the collision destruction &reaccumulation process.
New scientific results from theexploration robots on the surface
environment of asteroids.

Engineering goal
Improve robustness, accuracy andoperability of the new technology
implemented in Hayabusa, andmature it as a technology.

Rendezvous with a target orbit
using ion engines for deep space
propulsion.

Drop the exploration robot to theasteroid surface.
Take a sample of the asteroid
surface.

Engineering goal
Demonstrate impact object colliding
with a celestial body.

Construct a system to allow animpact device to collide with thetarget object and perform thatcollision with the asteroid.

2019/11/12

N/A

Collect the re-entry capsule onEarth.

Make the impact device collide in a
specified area.

 

Collect a sample of asteroid
subsurface material exposed during thecollision.

Achieved
Awaiting
achievement
confirmation• The red frame marks
the goals achieved by
the operation up toasteroid departure• For the spacecraft
operation (apart fromfuture academicachievements), allachievements thatshould be achieved
during the nearasteroid phase havebeen completed9

Science observations during nearby operationsummary(Project Scientist Seiichiro Watanabe)• 2018/7, 8Initial observations Box-A, Cmedium altitudegravity measurement, sub-Earth observations,
global observations of Ryugu, comprehension of the overall structure, landing point selection work.
• 2018/82019/9Box-B observationtotal of 7 observations of the south pole, north pole, morning / eveningside)• 2018/102019/10Box-C observation6 descents to 5 km altitude, in addition to the initial observation
• All observations use the ONC-T,TIR,NIRS3,LIDAR,• Low altitude observations also made for touchdowns, rehearsals, rover / lander separation operations etc.
• 2019/2/221st touchdown (secured sample expected from CAM-H observations)• 2019/3/8Observed descent to S01 area (natural crater, initial candidate area for TD2)• 2019/4/4Artificial crater generation with the SCI, successful continuous imaging of impact ejecta by DCAM3.
• 2019/4/25Successful SCI rater identification observation (specific comparison with 3/21 observation)• 2019/7/11 2nd touchdown about 20m from SCI crater (high probability of collection of subsurface material
evacuated from crater)

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Hayabusa2 reporter briefing

10Science observations during nearby operation(Project Scientist Seiichiro Watanabe)• 3 papers (+ cover) published in Science Magazine 4/19, and 1 MASCOT paper on 8/23
• Papers in international journals; Nature Astron., Astrophys. J., Icarus, Astron. & Astrophys.
Constraining the parent body,Top-shape generated by Sugita+ 2019 →past high-speed rotation
Confirm the presence of waterWatanabe+ 2019in minerals, Kitazato+ 2019
P = 7.63 hP = 3.50 h     
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Hayabusa2 reporter briefing11

3. Ryugu departure outreach“Good-bye Ryugu” CampaignSayonara RyuguWhy, Haya2?

ContentCall for messages about Ryugu andHayabusa2

ContentAccept questions via twitter which Project
members will respond to in real time.

PeriodNov 12Nov 18 from Ryugu departureannouncement until Ryugu disappears fromsight)

Date & timeNov 16Sat15:0016:30 JST

How to submit a message
On twitter: hashtag #SAYONARA_Ryugu

Tweet your question during the above time withthe hashtag #haya2_QA.
Anyone can ask any question! elementary
school students or younger, please ask yourparents for help)

To the project or letter (note below-right)
Messages may be shared The point where Ryugu will no longer be visible willbe posted on the Hayabusa2 website
2019/11/12

How to ask

Note Address
Hayabusa2 Project, 3-1-1 Yoshinodai, Chuo-ku,Sagamihara City, Kanagawa, 252-2510 , Japan

Hayabusa2 reporter briefing

124. Future plans
Operation schedule
November 13 at 10:05 JST planned Ryugu departure
November 1819
move to ion engine attitude Press briefings
December 19 (afternoon) Press briefing  Tokyo office

2019/11/12

Hayabusa2 reporter briefing

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