Next Space VLBI mission: VSOP-2

Y.Murata (ISAS/JAXA)

Next Generation Space VLBI WGH.Hirabayashi, M.Natori, P.G.Edwards, Y.Asaki, N.Mochizuki, T.Toda, … (ISAS/JAXA),

M.Inoue, S.Kameno, M.Tsuboi, Y.Kono, K.Asada, A.Doi, H.Nagai, H.Kobayashi, K.Bushimata, N.Kawaguchi, S.Iguchi, … (NAOJ)

T.Kondo, Y.Koyama (NICT)

K.Fujisawa (Univ. of Yamaguchi),

T.Omodaka(Univ.of Kagoshima),

H.Sudo (Univ. of Gifu), K.Wajima (KVN)

T.Kasuga (Hosei Univ.), S.Sawada-Sato (ASIAA)

International collaboratorsJPL, NRAO, ATNF, DRAO, JIVE/EVN, China, ..

VSOP

HALCA and VSOPHighly Advanced Laboratory for Communications and Astronomy

VLBI Space Observatory Programme

1.6 GHz (18 cm)5 GHz (6 cm)x[ 22 GHz (1.3cm)]

34,000 km

Launch: Feb. 1997ISAS M-V rocket

Resolution of360 μarcseconds　 at λ= 6 cm

Lobanov, A.P. 2003, SKA Memo 38

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Presentstatus

Resolution of current & future telescopes in all wavelength

Plasma torus

VSOP observation results

• FIRST Space VLBI Mission

• Physics of the Active Galactic Nuclear (AGN)– Structure and motion of the

AGN jets

– Torus around the AGN core

– Extremely high brightness temperature objects

(TB=1014 K)

Beamwidth 100 Rs at 5 GHz for M87

Plasma Torus in absorption5-years jet monitor of 1928+738

Jet Structure

VSOP publications

Advances

In Space

Research VSOP symposium

PASJ VSOP issue

Success of large scaleInternational Collaboration

HALCA Tracking Stations: NASA DSN (Goldstone, Tidbinbilla, Madrid), NRAO Green Bank, Usuda (ISAS)Navigation: NASA JPL, ISASCorrelators VLBA (NRAO), Penticton (DRAO, Canada), Mitaka (NAOJ) Radio Telescopes: VLBA, VLA, Green Bank 140 ft (NRAO), Arecibo, DSN 70m (GO, TI, RO), Jodrell Bank, Westerbork, Onsala, Effelsberg, Torun, Noto, Metsahovi, Kalyazin, Shanghai, Hartebeesthoek, ATCA, Hobart, Ceduna, Mopra, Usuda, Kashima (14 countries, 32 telescopes)

VSOP-2

VSOP-2 is the upgraded space VLBI mission following the VS

OP mission.

10 times higher sensitivity.

10 times higher frequency

observation

10 times higher resolution with ～ 40 μarcseconds 　 (43 GHz).

Observing band 8, 22, 43 GHz (Wavelength of 3.8, 1.3 and 0.7 cm)

Dual polarization

Phase-referencing capability

VSOP-2 Mission

Lobanov, A.P. 2003, SKA Memo 38

ＶＳＯＰ－２

Resolution of current & future telescopes in all wavelength

ＶＳＯＰ

Presentstatus

Characteristics of the future radio telescopes

Sensitivity

ResolutionHigherFrequency

SKA(Square Kilometer Array)

ALMA

VSOP-2

Launcher and orbit• Launcher : M-V rocket by JAXA

• Orbit : (cf HALCA)

– Apogee 25,000 km (21,300 km) Perigee 1,000 km (560 km)

– inclination 31° (31 °)

– period 7.5 hour (6.3 hour)

• Mass 910 kg (831 kg)

• Power 1,800 W (700 W)

• Launch : 2011 in earliest caes

VSOP-2 Science Targets

• Key science :– Jet structure, collimation and acceleration – Structure of plasma tori, accretion disks, BHs in acti

ve galactic nucleus (AGN)– Structure of magnetosphere in protostars

• Other science targets:– Galactic masers in star-forming region– Extragalactic Megamasers– Radio quiet quasars– X-ray binaries, SNR, gravitational lenses etc.

a-c: inclination　　　 20°

g-I: inclination　　　 45°

Look at the BLACK HOLE !?

Schwartschild………………...…..Extreme Kerr

　Model

VSOP-2 image

　Model

VSOP-2 image

Imaging of Accretion Disk　 ADAF 、 TB=109-10 K 　　 （ Standard Disk = 105K ）

Black Hole 10 Rg resolution @ M87 distance

(Takahashi et al. 2004)

Magneto-HydroDynamic Simulation (Meier et al. 2001)

Rotating accretion disk + Magnetic Fiels

Polarization Image byVSOP

VSOP-2 enables full-polarization Image

Dynamics of galaxies and the star forming regions using maser emission

• Mega-maser in NGC4258 type galaxies– Measurement of the proper

motion in short timescale

– Doppler shift measurement

– 3 dimensional dynamics

– Estimation of the central mass

• Star Forming Region• Late Type Stars

NGC4258 Miyoshi et al. 1995

VSOP-2 satellite• 9-m offset Cassegrain antenna with modular

structure– Light weight

VSOP-2 engineering developments

•Large deployable antenna for λ=7 mm •High data rate sampling of the data•1 Gbps data transmission•Cooled low noise amplifiers on board.•Development of the phase-referencing

Switching capability•Total satellite system design

Mass budgetPower budgetHeat control systemAttitude control systemPower supply systemStructure fit to the M-V fairing

Deployment mechanism of theModular antenna structure

• Same deployment mechanism as ETSVIII – modular antenna

structure

Launch 2006 ?

ETS-VIII(JAXA)

Deployment image of ETS-VIII

Deployment test of ETS-VIII

Development of a high accuracy antenna module

⑥

②

③

④ ⑤

⑦

構体中心軸

サポートブーム

①

対称鏡面

※ 放射面側から見る

Ｙａ

Ｘａ

設計対象 鏡面

Deployment system test.

Confirmed mechanical structure

Deployment of the module

Radiation test of the high speed A/D LSI

Total dose test (April 2001)Single event test （ August 2001)

10 Gbps 1 bit A/D1:16 DEMUX

Correlator

Heavy ion beam

• 4 reaction wheels and 2 CMG for rapid switching

•CMG•changes the direction of the spin axis set by the reaction wheels

•Simulations•Assuming :

•Switching cycle 1 minute•Amplitude 3.5 °•Flexible structure body

Attitude error < 0.005°

separation angle < 3°

Switching cycle < 1min.

CMG control test

Solution of high torque actuator

International Collaborations

• International collaboration based on VSOP experience– Correlators, tracking stations, orbit determination

– Ground telescopes commitments based on GVWG (Global VLBI Working Group) discussion.

• Many new Ground Telescopes • VERA 4 stations, Yamaguchi, Uchinoura ,

• KVN 3 stations,

• Urumqi, Delingha, Beijing

• Sardinia, Yebes

• GBT

– Possibility of SKA with VSOP-2

Status of VSOP-2

• JAXA/ISAS– Developments are going.– The VSOP-2 mission proposal was

submitted to ISAS Science Steering Committee in October, 2003, but could not go to the budget request.

– Revised version of the proposal will be submitted soon as an M-V mission @ 2011

– 3 missions are the candidates to be approved.

• NAOJ– Space VLBI project office for VSOP-2 is started from last April– NAOJ and ISAS will be core institute for the VSOP-2 mission, as we

did in the VSOP mission.