INSAT-1B was an Indian communications satellite which formed part of the Indian National Satellite System. Launched in 1983, it was operated in geostationary orbit at a longitude of 74 degrees east.[3] At the end of its seven-year design life it was replaced by the newly launched INSAT-1D, dropping to backup status. In 1992, it was relocated to 93° east, before being decommissioned in August 1993.[3]
Built by Ford Aerospace and operated by the Indian National Satellite System,[3] INSAT-1B was based upon a custom satellite bus developed for the INSAT-1 series of satellites. It had a mass at launch of 1,152 kilograms (2,540 lb), and was expected to operate for seven years. The spacecraft carried twelve C and three S band transponders, powered by a single solar array.[3] A stabilisation boom was used to counterbalance radiation torques from the satellite's asymmetrical design.[4] The spacecraft was propelled by an R-4D-11apogee motor.
INSAT-1B satellite being deployed from the Space shuttle.Satellite being deployed from the payload bay of Space Shuttle Challenger.
After some initial problems deploying its solar array,[6] INSAT-1B became operational in October 1983. It was located at 74° east for most of its operational life, before being moved to 93° east in 1992. In August 1993 it was decommissioned and raised to a graveyard orbit slightly above geosynchronous altitude.[3] As of 14 November 2013, it is in an orbit with a perigee of 35,741 kilometres (22,208 mi), an apogee of 35,846 kilometres (22,274 mi), inclination of 14.69 degrees and an orbital period of 23.93 hours.[2]
Launches are separated by dots ( • ), payloads by commas ( , ), multiple names for the same satellite by slashes ( / ). Crewed flights are underlined. Launch failures are marked with the † sign. Payloads deployed from other spacecraft are (enclosed in parentheses).
