SBS 6 was a

geostationary 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 geosynchronous orbit in altitude ...

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. C ...

designed and manufactured by

Hughes Hughes may refer to: People * Hughes (surname) * Hughes (given name) Places Antarctica * Hughes Range (Antarctica), Ross Dependency * Mount Hughes, Oates Land * Hughes Basin, Oates Land * Hughes Bay, Graham Land * Hughes Bluff, Victoria La ...

(now

Boeing The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and product ...

) on the

HS-393 The Hughes 393 (sometimes referred to as the HS-393) is a communications satellite bus introduced in 1985 by Hughes Space and Communications Company. It was a spin-stabilized bus that had twice as much power as the HS-376 platform. Design The ...

platform. It was originally ordered by

Satellite Business Systems Satellite Business Systems (SBS) was a company founded by IBM, Aetna, COMSAT (and later wholly purchased by IBM and then subsequently sold to MCI), that provided private professional satellite communications through its SBS fleet of FSS geosy ...

, which later sold it to

Hughes Communications Hughes Network Systems, LLC is a wholly owned subsidiary of EchoStar. It is headquartered in Germantown, Maryland and provides satellite internet service. HughesNet has over 1.3 million subscribers in the Americas. History Hughes Communications ...

and was last used by

Intelsat Intelsat S.A. (formerly INTEL-SAT, INTELSAT, Intelsat) is a multinational satellite services provider with corporate headquarters in Luxembourg and administrative headquarters in Tysons Corner, Virginia, United States. Originally formed as In ...

. It had a K_u band payload and operated on the 95°W longitude.

Satellite description

The spacecraft was designed and manufactured by

on the

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 opposed to specially produced satellites. Bus-d ...

. It had a launch mass of , a mass of after reaching

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 geosynchronous orbit in altitud ...

and an 8-year design life. When stowed for launch, its dimensions were long and in diameter. With its solar panels fully extended it spanned . Its power system generated approximately 2,350

Watt The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James Wa ...

s of power thanks to two cylindrical solar panels. It also had a two 38 Ah NiH₂ batteries. These panels used K7 and K4-3/4 solar cells and were more than twice the number than on the

HS-376 The Boeing 376 (sometimes referred to as the BSS-376, and previously as the HS-376) is a communications satellite bus introduced in 1978 by Hughes Space and Communications Company. It was a spin-stabilized bus that the manufacturer claims was th ...

. Its propulsion system was composed of two

R-4D The R-4D is a small hypergolic rocket engine, originally designed by Marquardt Corporation for use as a reaction control system thruster on vehicles of the Apollo crewed Moon landing program. Today, Aerojet Rocketdyne manufactures and markets m ...

LAE Lae () is the capital of Morobe Province and is the second-largest city in Papua New Guinea. It is located near the delta of the Markham River and at the start of the Highlands Highway, which is the main land transport corridor between the Highl ...

with a thrust of . It also used two axial and four radial

bipropellant The highest specific impulse chemical rockets use liquid propellants (liquid-propellant rockets). They can consist of a single chemical (a monopropellant) or a mix of two chemicals, called bipropellants. Bipropellants can further be divided into ...

thrusters for station keeping and

attitude control Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle ...

. It included enough propellant for orbit circularization and 8 years of operation. Its payload was composed of a multi horn antenna by thirty 45 MHz K_u band

transponders In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a flight trans ...

, of which 19 were active and 11 spares. It had a total active bandwidth of 855 MHz. The K_u band transponders had a

TWTA A traveling-wave tube (TWT, pronounced "twit") or traveling-wave tube amplifier (TWTA, pronounced "tweeta") is a specialized vacuum tube that is used in electronics to amplify radio frequency (RF) signals in the microwave range. The TWT belongs t ...

output power of 41

s. It also had an omnidirectional command and telemetry antenna.

History

In 1985

decided to order a more powerful satellite than the

based previous satellites. Thus, it ordered the

based SBS 6 from

, becoming the first customer of the platform. On October 12, 1990, SBS 6 was finally launched by an

Ariane 44L The Ariane 4 was a European expendable space launch system, developed by the ''Centre national d'études spatiales'' (CNES), the French space agency, for the European Space Agency (ESA). It was manufactured by ArianeGroup and marketed by Arian ...

from

Kourou Kourou () is a commune in French Guiana, an overseas region and department of France in South America. Kourou is famous for being the location of the Guiana Space Centre, the main spaceport of France and the European Space Agency (ESA). It i ...

ELA-2 ELA-2, short for Ensemble de Lancement Ariane 2 ( French for Ariane Launch Area 2), was a launch pad at the Centre Spatial Guyanais in French Guiana. It was used by Arianespace for two Ariane 3 launches (V17 in 1986, V25 in 1988), the second Aria ...

at 22:58 UTC. In April 2009, SBS 6 finally decommissioned and put on a

graveyard orbit A graveyard orbit, also called a junk orbit or disposal orbit, is an orbit that lies away from common operational orbits. One significant graveyard orbit is a supersynchronous orbit well beyond geosynchronous orbit. Some satellites are moved int ...

References

{{Orbital launches in 1990 Communications satellites Communications satellites in geostationary orbit Spacecraft launched in 1990 Satellites using the HS-393 bus