INSAT-1A was an Indian

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transponder; it creates a communication channel between a source transmitter and a Rad ...

which formed part of the

Indian National Satellite System The Indian National Satellite System or INSAT, is a series of multipurpose geostationary satellites launched by the ISRO, Indian Space Research Organisation (ISRO) to satisfy telecommunications, broadcasting, meteorology, and search and rescu ...

. Launched in 1982, it was operated in

geostationary orbit A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular orbit, circular geosynchronous or ...

at a longitude of 74° east. Following a series of failures, the satellite was abandoned in September 1982, less than six months into a seven-year mission. Built by Ford Aerospace and operated by the

, INSAT-1A was based upon a custom

satellite bus A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held. Bus-derived satellites are less customized than specially-produced satelli ...

developed for the INSAT-1 series. It had a mass at launch of , and was expected to operate for 7 years. The spacecraft carried 12 C and 3

S band The S band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a part of the microwave band of the electromagnetic spectrum covering frequencies from 2 to 4 gigahertz (GHz). Thus it crosses the conventiona ...

transponders, powered by a single solar array.

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

was contracted to launch INSAT-1A using a Delta 3910 rocket with a

PAM-D The Payload Assist Module (PAM) is a modular upper stage designed and built by McDonnell Douglas (Boeing), using Thiokol Star-series solid propellant rocket motors. The PAM was used with the Space Shuttle, Delta, and Titan launchers and carrie ...

upper stage. The launch occurred at 06:47 UTC on 10 April 1982, from Launch Complex 17A at

Cape Canaveral Air Force Station Cape Canaveral Space Force Station (CCSFS) is an installation of the United States Space Force's Space Launch Delta 45, located on Cape Canaveral in Brevard County, Florida. Headquartered at the nearby Patrick Space Force Base, the sta ...

. The satellite was successfully inserted into geosynchronous transfer orbit, from which it raised itself into

. It received the International Designator 1982-031A and

Satellite Catalog Number The Satellite Catalog Number (SATCAT), also known as NORAD Catalog Number, NORAD ID, USSPACECOM object number, is a sequential nine-digit number assigned by the United States Space Command (USSPACECOM), and previously the North American Aerospac ...

13129. Following launch, INSAT-1A had some initial problems deploying its antennas, solar array and stabilisation boom. The C-band antenna could not be deployed for twelve days, and the solar array failed to extend fully, preventing the spacecraft generating enough power to conduct weather observation. The satellite's S-band transponders subsequently overheated and failed. The stabilisation boom failed to deploy altogether. Early in the satellite's mission a fault in a valve in its attitude control system was detected which caused the spacecraft to expend propellant at a greater rate than expected. On 4 September 1982 the satellite's primary Earth-tracking sensor was temporarily deactivated to protect the system while the Sun passed through its field of view. Owing to the failure of the stabilisation boom, the backup sensor was not oriented in the correct direction, instead being oriented towards the Moon, which overloaded it and shut down the sensor. The satellite exhausted its remaining propellant supply trying to regain Earth-lock, and was abandoned on 6 September. Due to the sudden nature of its failure, INSAT-1A was not removed from geosynchronous orbit. As of 10 November 2013 it is in an orbit with a

perigee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

of , an

apogee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

of ,

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Eart ...

of 14.59 degrees and an

orbital period The orbital period (also revolution period) is the amount of time a given astronomical object takes to complete one orbit around another object. In astronomy, it usually applies to planets or asteroids orbiting the Sun, moons orbiting planets ...

of 23.93 hours.

References

{{Orbital launches in 1982 INSAT satellites Spacecraft launched in 1982 1982 in India Derelict satellites orbiting Earth