VSOP-2 project Update Hisashi Hirabayashi /JAXA VSOP-2 Project status Tracking Station mtg,, Feb. 19 & 20, 2006, OAM Madrid VSOP-2 project Update Hisashi Hirabayashi /JAXA VSOP-2 Project status Spacecraft and instruments Act 2
VSOP-2 Project Budget request was approved Dec. 2006 Internal Reviews; ISAS System Definition Review March 19, or 26. JAXA Project Review March, or April Project formal start April 1, 2007 (FY2007 start day) Project Manager Prof. Saito Project Scientist Prof. Tsuboi (transfer from Nobeyama R. O. Director after Hirax’s retirement ) Meetings; VSOP Lessons Learned mtg in Hakone April org.ed by YH/HH/LIG VSOP-2 symposium in Sagamihara Dec. 2007 Satellite ETS-VIII (now Kiku-VIII) launched and 2 LDRs were successfully deployed (Dec, 25-26, 2006). Launch in Jan.-Feb. 2012 is current plan, but ? Still Uncertainty in Launcher VLBI-Link 40GHz up and 37GHz down link, we propose.
30,000 km HALCA and VSOP (1997 - 2006) 1.6 GHz (18 cm) 5 GHz (6 cm) VLBI Space Observatory Programme HALCA and VSOP (1997 - 2006) Highly Advanced Laboratory for Communications and Astronomy 1.6 GHz (18 cm) 5 GHz (6 cm) Resolution of 360 μarcseconds at λ= 6 cm 30,000 km Launch: ISAS M-V rocket Feb. 12, 1997 10 years anniversary, a week ago ! Time flies as rockets do.
HALCA/VSOP project started in April 1989 HALCA Launch in Feb. 1997 HALCA last command November 30, 2006 (3213 days after launch) HALCA/VSOP was a 17 years project, and terminated in March 2006. Lessons Learned mtg in Hakone, April l6, 17, 2007
ISAS Astronomy satellites Series Astro-E launch failure 2002 ? Astro-E II = Suzaku X-ray 2005 Astro-F = Akari IR 2006 Solar-B = Hinode Sun 2007 last usage of M-V rocket here is a long gap. Astro-G = ??? Radio 2012 NeXT X-ray
VSOP-2 spacecraft In-Orbit Configuration 7 modules Feed/LNA Mass (wet) 910Kg Power 1,800 W In-Orbit Configuration 7 modules Sub-reflector with 3-dim adjust. Solar Paddle Solar Paddle Feed/LNA 9m offset Cassegrain Antenna with Modular Structure Link Antenna Launch Configuration in M-V rocket Main-Reflector with 2-dim adjust
Modular antenna structure for VSOP-2 deployment mechanism and back-structure same as ETS-VIII but with new antenna surface design (Study since 2000 with budgets) ETS-VIII(Kiku-VIII) was Launched in Dec. 2006, and was successfully Deployed as below. ½ scale 7 modules successful deployment test in 2006 Oct. by Ariane piggyback We use … NASDA HPでcheck!
VLBI Link system Proposed frequency Astro-G High Gain Antenna Diameter: 80cm Astro-G Proposed frequency VLBI Data Downlink Frequency 37-38 GHz Bit Rate 1 Gbps Modulation QPSK TX-Power 20 W Phase Transfer Uplink Frequency 40 GHz No Modulation TX-Power 10 W Ground Link Station Diameter >10m Data Storage Data Storage Capacity 4 TB / 8 hours H Maser Phase Comparison
Phase-referencing observation Study Rapid switching between target and phase reference sources Increase sensitivity Astrometric studies Requirements 3 degeree separation within 1 min cycle High torque actuator : CMG (Control Moment Gyro) with 4 Reaction Wheels Orbit determination accuracy: < 5cm with GPS + SLR Problems; Expensive CMGs OD accuracy cannot be enough Consideration or Decision needed ?? For other option, we think the capability of phase referencing. Off course, observing two objects at same time is better. And frequency switching is also available for improvement of sensitivity. But rapid switching or tilting is the most realistic method, for the present. So the requirements for phase referencing are these. High torque actuator for rapid maneuver. Because the phase error is orbit error times separation angle, now we assume maximum separation 3 degree. Control Momentum Gyro(Honeywell)
Solar-B, Solar X-ray/Opt/UV Observatory, was renamed HINODE which means “sunrise”. It was launched near the sunrise into sun-synchronous orbit. HINODE launch by M-V-7 (the last M-V launch) September 23, 2006 US/European contribution to HINODE On-board Instruments (US,UK) Tracking support (ESA) Uncertainties for Astro-G launcher H-IIA other ? Orbit ? in case of shared launch
VSOP-2 Mission, Concluding Remarks Astro-G Tracking Meeting, Feb, 2007, OAM Madrid VSOP-2 Mission, Concluding Remarks 2nd Generation space-VLBI mission VSOP-2 is now funded for Astro-G satellite launch in Feb. 2012, And the project will formally start in April 2007. (Phase-A to Phase-B) Design study and mission planning are in progress, Group is being established in Japan. VSOP-2 Orbit
US/Japan meeting, Socorro, Feb. EVN Directors mtg, Firenze, May 2006 US/Japan meeting, Socorro, Feb. EVN Directors mtg, Firenze, May Europe/Japan mtg, JIVE, June COSPAR GA, Beijin, July IAU GA, Prague, Aug. EVN symp. Torun, Sept. Tracking meeting, Pasadena, Oct. Nov. EVN Directors mtg,Bonn, Nov. 2007 Lessons Learned mtg, April 18, 19, Japan (?) Europe/US/Japan mtg, May, Bonn VSOP-2 symposium Dec. 3-6. ISAS VSOP-2 Selected Contractor Selection (Now) Budget Announciation (Dec. 2006) ISAS Mission Def. Review JAXA Review VSOP-2 Project start (April 2007)
5 Stations Tracking Network for HALCA VSOP-2 tracking station(s) in the European longitude Yebes South Africa ? 10m 64m 13m 40m 43 GHz Space- Ground baseline at Yebes HALCA-Usuda first fringes (via 10m) (64m) at 1.6 GHz This slide was shown to Dr. Southwood and ESA members more than once.
VLBI Two-Way Link Need to make basic design soon so that each partner can understand and explain to funding agencies. Need to establish an international Study team by interested (or approved) parties. VSOP had 5 stations network with 3 different design; Usuda (ISAS) 1 DSN (JPL) 3 GB(NRAO) 1 with compatibility test One group to design one scheme is important. OFDM (8CH, QPSK) 1CH、QPSK, 16QAM,… Analog
Common design and delivery (draft thought) Make common basic design Review at April mtg at Sagamihara Common frequencies with NTS engineers’ presence with RFI consideration with some more details RF part feed (antenna dependent) polarizer / diplexer IF and LO frequency chain and O/E, E/O (station dependent) Demodulator/ Modulator module exist ? (JPL?) Japanese FPGA-based design ? Doppler compensation (unified open loop !) Time/ phase correction measurement circuitry to be confirmed Control and Logging Computer and Software which cmputer ? language? later Station Prarticipation Who can work, or deliver in what part how many spare parts ?