The VLBI Space
Observatory Program


VSOP: An Artist's Impression. Click here for the full image (270 kb)    IAA presentation to the VSOP team. Click for the full image

IAA Award to VSOP Team

The VSOP (VLBI Space Observatory Programme) mission is led by the Institute of Space and Astronautical Science, in collaboration with the National Astronomical Observatory of Japan.

The technique of Very Long Baseline Interferometry (VLBI) uses widely spaced telescopes to synthesize a telescope as large as the greatest distance between the telescopes. The reason for doing this is to study celestial radio sources in more detail, i.e. at higher resolution.

The first VSOP satellite was successfully launched 12 February 1997 on the new ISAS M-V rocket from the Kagoshima Space Center. The satellite, renamed HALCA after its successful launch, sucessfully deployed an 8 meter diameter radio telescope in orbit on 27 & 28 February 1997.

HALCA is in an elliptical Earth orbit, with an apogee height of 21,000km and a perigee height of 560km, which enables VLBI (Very Long Baseline Interferometry) observations on baselines up to three times longer than those acheivable on Earth.
An upper illustration expresses the image of a composed telescope.

Observations will be made at 1.6GHz (18cm), 5GHz (6cm) and 22GHz (1.3cm). First fringes between the satellite and ground radio telescopes were found at the Mitaka correlator in May, and at the Penticton and Socorro correlators in June. First images made with data from the satellite and ground radio telescopes have been made at 1.6GHz and 5GHz.

On November 30, 2005, after long operation of 8 years and 9 months, HALCA performed its last operation and retired.
HALCA breathes its last


General Information General Information 
What is VSOP?,     Science Goals,     The Satellite,     The Rocket,     History,     Milestones,     The VISC
VSOP Survey Program [ The VLBA pre-launch survey ], 
Papers,   Images,   The VSOP Symposium 2000  
Information for Observers
Common Use Program [ Announcement of Opportunity,   General Observing Time,   Key Science Programs ], 
Public Data List [ Observation Status (obsolete) ],   Observers FAQ,  
Data Reduction [ HALCA Calibration,   Ground Telescope Calibration ], 
VSOP Standard Acknowledgments
More information 
VSOP Mission Operations,    Optical LInked Vlbi Experiment (OLIVE) (Japanese),   
Back numbers of VSOP Newsletter,    Update history of thie site,   
Keywords around VLBI (Japanese),    Links to Related Sites,    HALCA Photo Album (Japanese)

About This Site ... and its awards

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ISAS / JAXA Electric wave astromony group