Current Status of Hayabusa2

Yuichi Tsuda, Project Manager, Hayabusa2 ProjectJapan Aerospace Exploration Agency

Small Body Assessment Group 18th Meeting, Jan.18, 2018

Sun

Launch(Dec.2014 )

Earth Sw ing-by(Dec.2015)

Ryugu Arrival( Jun-Jul.2018)

Ryugu Orbit

Hayabusa2 T rajectory

Earth Orbit

Ion Eng ine Powered Cruise # 1（Mar.22 , 201６～May.20 , 2016）

Ion Eng ine Powered Cruise # 2（Nov.22 , 2016～Apr.26 , 2017）

Ion Eng ine Powered Cruise # 3( Jan.10 , 2018～Jun.5 , 2018)

Present Status of Hayabusa2 (as of Jan.16, 2018)

• Traveled 2.79 billion km (w.r.t heliocentric inertial frame)• Solar distance 1.25AU.• Earth distance 2.08AU (RTLT=34min.)• Just started the final Ion Engine burn before the asteroid rendezvous on Jan 10.

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We are here!

＜Recent Ops.＞2017Apr.15 2nd IES Burn completedApr.25-26 IES trim burnMay16-28 Jupiter/star calibrationMay.30-Jun.1 RCS test burnSep.5 Spacecraft clock resetJul.18-Nov.14 Science instruments

program updateNov.18,28 DSN-SSOC realtime Doppler

transfer testDec.2 DSN-UDSC uplink transfer

testDec.26-27 IES test burn

2018Jan.10 3rd term IES Burn Start＜Near Future Ops.＞~May Ryugu first lightJun.5 IES burn completes. OpNav

begins.

Recent / Near Future Cruise Operation

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Sun Earth

IES Start 2016.3.22

IES Stop 2016.5.20

IES Start 2016.11

IES Stop 2017.4

IES Stop 2018.6

IES Start 2018.1

Sun

EarthOpNav Rendezvous Phase start (Jun.5, 2018)

Ryugu Arrival(Jun.21-Jul.5, 2018)

Proximity Operation Plan

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20185 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12

2019

・Asteroid Arrival (20km)

・Approach Guidance Start(2500km

)・Ion Engine Stop

・Mid Altitude O

bservation Descent1 (5km)

・Gravity M

easurement Descent (1km

)・TD1 Rehearsal 1 (100m

)・M

INERVA-II Deploym

ent (50m)

・TD1 Rehearsal 2 (50m)

・TD1 (0m)

・MASCO

T Deployment (50m

)

Conjunction Period

Hot Asteroid Period

・TD2 Rehearsal 2 (50m)

・TD2 (0m)

・Pre-Impact Descent (1km

)・Kinetic Im

pact (500m)

・Crater Search Descent (1km)

Pin-Point TD Campaign (m

ax 4 descent)

Landing Site Selection1 Landing Site Selection2&3

・Mid Altitude O

bservation Descent2 (5km)

・Asteroid Departure

・MIN

ERVA-II Deployment (50m

)

Typical plan, Actual schedule fixed after arrival

Spacecraft ‘hovers’ at 20km altitude. All descent ops listed here are critical operations.

Prox Operation Training Campaign 2017

• Landing Site Selection (LSS) Training (2Q-3Q, 2017)– Purpose: Verification of LSS process

• Decision making framework/criteria, Tools and interface, ...– Trainee

• 100+ participants, JAXA engineering, Science (International), MASCOT team

– Training data• Asteroid images (CG) based on actual observation operation plan• Science data (Thermal, near infra-red, LIDAR data, gravity, …)• Navigation data (position & velocity of S/C), Attitude data.

• Real-Time Integrated Operation (RIO) Training (4Q, 2017-1Q, 2018)– Purpose: Real-time operation training, Verification of ground support tools

• Touchdown operation, Impact operation, rover landing…– Trainee: all the operation staffs– Training data

• Asteroid images (CG, real-time)• Telemetry data (with communication delay)

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Landing Site Selection Practice step1: ‘God team’ creates Ryugoid

• Virtual asteroid ‘Ryugoid’ in place of mysterious Ryugu.

• Assume from the formation history of Ryugoid. The shape and all the other properties were derived from the history.

• Each property was Intendedly deviated from known Ryugu property.

• The rotation state is randomly selected from public via Twitter.

• Shape model: 25cm resolution, 370 million polygon.

• Observation data generated based on actual operation plan & actual instruments performance.– Generates attitude/trajectory simulation data

based on operation plan– Observation data and their ancillary data

generated based on the simulation data.– Goes through all the ground pipe line

process as it really is.5

Landing Site Selection Practice step2: Sci.&Eng. teams to solve the problem

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Touch Down Secondary Target

Touch Down Primary Target

Landing Site Decision

EvaluationModeling/AnalysisObservation(Simulated date generation)

Jan-Jun, 2017

May-Aug, 2017

Jun-Aug, 2017

Sep 4, 2017

Surface feature of Ryugoid

Forest Hemisphere

Snow White C.

Doc C.

Grumpy C.

Sleepy C. Happy C.

Bashful C.

Sneezy C.

Dopey C.

Apple R.Comb R.

Queen C.

Piece R.

hyb2_onc_180717_122656_tvf_l1a_LSS_TEST

Mashroom R.

Axe R.

Herb R.Ribbon R.

Yodel M.

Seven M.

Hut Regio

C. ... CraterM. ... MontesP. ... PlanitiaR. ... RockLumberjack C.

Fa i rly Regio

Zone B

Zone A

Seven Dwarfs

Kingdom Hemispherehyb2_onc_180717_083856_tvf_l1a_LSS_TEST

Apple R.

Comb R.

Snowman C.

Seven M.Queen C.

Prince C.

Coffin R.

Norm R.

Burial Pi tMirror P.

Boar R.

Squire C.Yodel M.

Grimms M.

C. ... CraterM. ... MontesP. ... PlanitiaR. ... Rock

White P.

Sneezy C.

Coal Hat R.

Lumberjack C.

Horse C.

Bi ldung P.Zone DZone D2

Zone C

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Landing Site Selection Practice step3: Landing Site Decision

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MA-1 MA-2MA-3

MA-4

BAD

ED2

C

MI-1

Primary set：Zone B, MA-2, MI-1Backup set：Zone D2, MA-1, MI-1

Two set of Mother spacecraft landing, MASCOT lander landing, MINERVA-II rovers landing sites are derived based on safety and scientific value.

Real-time Integrated Operation Practice (RIO)

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TRIO (Training of RIO) Jan-Sep,2017: 18 run – 13 crush – 5 success/okeyRIO Oct.2017-Apr.2018: total 30 run planned, 13 run – 4 crush – 9 success/okey.

RIO Example: MASCOT Release Operation Practice (Oct.19-20,2017)

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MASCOT Descent Aim Point

Descent start (-1m/s)↓

Slow Down (-0.1m/s)↓

60m arrival/release↓

Ascent to 3km↓

Hovering

View of Optical Navigation Camera ONC-W1

“Imagining Ryugu” Space Art Contest

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http://www.hayabusa2.jaxa.jp/topics/20171227_e/

Can you predict Ryugu appearance better than scientists?

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Thank you!