The HALCA satellite is an 8 meter diameter radio telescope used for Very Long Baseline Interferometry. It is now in an orbit with an apogee altitude of 21,400 km and a perigee altitude of 560 km. The elliptical orbit will allow imaging of celestial radio sources by the satellite and ground based telescopes, with good (u,v) plane coverage and high resolution. The orbit has an inclination of 31 degrees, and a period of about 6.3 hours. It was launched in February 1997
