Arabsat-1B

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title: "Arabsat-1B" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["1985-in-spaceflight", "derelict-satellites-orbiting-earth", "spacecraft-launched-in-1985", "satellites-using-the-spacebus-bus", "satellites-of-saudi-arabia", "1985-in-saudi-arabia"] description: "Saudi Arabian communications satellite" topic_path: "general/1985-in-spaceflight" source: "https://en.wikipedia.org/wiki/Arabsat-1B" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Saudi Arabian communications satellite ::

::data[format=table title="Infobox spaceflight"]

Field	Value
name	Arabsat-1B
image	STS-51-G Arabsat 1-B deployment.jpg
image_caption	Deployment of Arabsat-1B from STS-51-G
mission_type	Communication
operator	Arabsat
COSPAR_ID	1985-048C
mission_duration	7 years
spacecraft_bus	Spacebus 100
manufacturer	Aérospatiale
launch_mass	1270 kg
launch_date	UTC
launch_rocket
STS-51-G / PAM-D
launch_site	Kennedy LC-39A
launch_contractor	NASA
deactivated
orbit_reference	Geocentric
orbit_regime	Geostationary
orbit_period	24 hours
orbit_longitude	26° East
apsis	gee
trans_band	2 E/F-band
25 G/H-Band
::

| name = Arabsat-1B | image = STS-51-G Arabsat 1-B deployment.jpg | image_caption = Deployment of Arabsat-1B from STS-51-G

| mission_type = Communication | operator = Arabsat | website = | COSPAR_ID = 1985-048C | SATCAT = | mission_duration = 7 years

| spacecraft_bus = Spacebus 100 | manufacturer = Aérospatiale | dry_mass = | launch_mass = 1270 kg | power =

| launch_date = UTC | launch_rocket = STS-51-G / PAM-D | launch_site = Kennedy LC-39A | launch_contractor = NASA | entered_service =

| disposal_type = | deactivated =

| orbit_epoch = | orbit_reference = Geocentric | orbit_regime = Geostationary | orbit_periapsis = | orbit_apoapsis = | orbit_inclination = | orbit_period = 24 hours | orbit_longitude = 26° East | orbit_slot = | apsis = gee

| trans_band = 2 E/F-band 25 G/H-Band | trans_frequency = | trans_bandwidth = | trans_capacity = | trans_coverage = | trans_TWTA = | trans_EIRP = | trans_HPBW = 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 1270 kg, and an expected operational lifespan of seven years.

History

Arabsat-1B was launched aboard 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. 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. In October 1991, a problem developed with the spacecraft's attitude control system, causing it to drift eastward out of control. The same fault had developed aboard its sister satellite, Arabsat-1A, a month earlier. It failed completely in early 1992.

References

References

1. Krebs, Gunter. "Arabsat 1A, 1B, 1C / Insat 2DT". Gunter's Space Page.
2. McDowell, Jonathan. "Launch Log". Jonathan's Space Page.
3. Wade, Mark. "Arabsat". Encyclopedia Astronautica.
4. "Arabsat 1B". TSE.
5. "Arabsat 1A". TSE.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::