Arabsat-1B

Arabsat-1B

Deployment of Arabsat-1B from STS-51-G
Mission type	Communication
Operator	Arabsat
COSPAR ID	1985-048C
SATCAT no.	15825
Mission duration	7 years
Spacecraft properties
Bus	Spacebus 100
Manufacturer	Aérospatiale
Launch mass	1,270 kilograms (2,800 lb)
Start of mission
Launch date	17 June 1985, 11:33:00 (1985-06-17UTC11:33Z) UTC
Rocket	Space Shuttle Discovery STS-51-G / PAM-D
Launch site	Kennedy LC-39A
Contractor	NASA
Orbital parameters
Reference system	Geocentric
Regime	Geostationary
Longitude	26° East
Period	24 hours
Transponders
Band	2 E/F-band 25 G/H-Band

Arabsat-1B was a Saudi Arabian communications satellite which was operated by Arabsat. It was used to provide communication services to the Arab States. It was constructed by Aérospatiale, based on the Spacebus 100 satellite bus, and carried two NATO E/F-band (IEEE S band) and twenty five NATO G/H-Band (IEEE C band) transponders. At launch, it had a mass of 1,270 kilograms (2,800 lb), and an expected operational lifespan of seven years.^[1]

History

Arabsat-1B was launched aboard Space Shuttle Discovery on mission STS-51-G. Discovery was launched from LC-39A at the Kennedy Space Center at 11:33:00 GMT on 17 June 1985.^[2] It was deployed from Discovery, and boosted to a geosynchronous transfer orbit by means of a PAM-D upper stage. Sultan bin Salman bin Abdulaziz Al Saud flew aboard the Shuttle to supervise deployment, becoming the first Saudi citizen and first member of royalty to fly in space. Morelos 1 and Telstar 303 were also deployed on the same mission.

Arabsat 1B was placed into a geosynchronous orbit at a longitude of 26° East.^[3] In October 1991, a problem developed with the spacecraft's attitude control system, causing it to drift eastward out of control.^[4] The same fault had developed aboard its sister satellite, Arabsat-1A, a month earlier.^[5] It failed completely in early 1992.^[4]

See also

• 1985 in spaceflight

References