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|
 Eutelsat 28A, a Spacebus 3000 | |
| Manufacturer | Thales Alenia Space |
|---|---|
| Country of origin |  France |
| Applications | Communications |
| Specifications | |
| Power | 16 kW |
| Regime | Geostationary |
| Design life | 15 years |
| Production | |
| Status | In production |
| On order | 7 |
| Built | 74 |
| Launched | 74 |
| Failed | 1 |
| Lost | 4 |
| Maiden launch | 1985 |
| Last launch | 20 August 2015 |
Spacebus is asatellite bus produced at theCannes Mandelieu Space Center in France byThales Alenia Space. Spacebuses are typically used forgeostationarycommunications satellites, and seventy-four have been launched since development started in the 1980s. Spacebus was originally produced byAérospatiale and later passed toAlcatel Alenia Space. In 2006, it was sold toThales Group as Thales Alenia Space.[1]
The first Spacebus satellite,Arabsat-1A, was launched in 1985. Since then, seventy-four have been launched, with one more completed, and six outstanding orders. The launch of the 50th Spacebus satellite,Star One C1, occurred in November 2007.[2] It was a Spacebus 3000B3, launched by anAriane 5 rocket flying from theGuiana Space Centre inKourou, French Guiana.
Several variants have been built: the earlySpacebus 100 andSpacebus 300; followed by theSpacebus 2000, optimised for launch on theAriane 4 carrier rocket; and the subsequent modularSpacebus 3000 and4000 series, designed for use with the Ariane 5 rocket.
Aérospatiale had produced a number of satellites, includingSymphonie, with the German companyMesserschmitt. On 9 December 1983,[3] the two companies signed theFranco-German Spacebus Agreement. The Spacebus designation was first applied to satellites which were under construction by Aérospatiale when the programme started. These included three satellites forArabsat, which became theSpacebus 100 series, and five further satellites: two forDeutsche Bundespost, two forTéléDiffusion de France, and theSwedish Space Corporation'sTele-X, which became theSpacebus 300 series. Later series' names were followed by a number indicating the approximate mass of the bus in kilograms.[4] Spacebus designations were not retroactively applied to previously launched satellites.
Spacebus satellites consist of a satellite bus, which provides power, propulsion, and other subsystems necessary for the satellite's operation, and a payload which is customisable according to the customer's requirements. The bus was designed to be adaptable to perform various missions; however, as of 2009, only communications satellites have been ordered. It was also designed to be adaptable when the capacity of launch systems increased.
The bus is made ofcarbon fibre with acomposite honeycomb structure.[when?] It contains fuel tanks, equipment to interface with a carrier rocket, and other critical systems. External panels contain equipment such as solar panels, payload, and engine. The payload, developed separately from the bus, takes up three panels. Once it has been outfitted withtransponders or other equipment, it is transported to Cannes-Mandelieu, where it is integrated onto the bus.
The satellites are powered by rigidsolar panels. Several configurations are used depending on the amount of power the satellite requires.Batteries to store this power are produced by theBelgian companyETCA.[which?] Early satellites usednickel-hydrogen batteries, while later spacecraft uselithium-ion batteries.[citation needed]
Spacebus satellites use bipropellant,liquid-fuelled chemical engines to achieve orbit and subsequently performstation-keeping.Electric propulsion was used on theStentor andAstra 1K satellites, both of which were subsequently involved in launch failures. Spacebus Neo will be an electric propulsion satellite. Athree-axis stabilisation system is used for attitude control.[citation needed]
Spacebus satellites are compatible with a large number of carrier rockets, particularly theAriane family. As the Ariane's performance has increased, the satellites' capacities have increased accordingly.[5]
Three Spacebus 100 satellites were produced forArabsat to serve the 22 members of theArab League.[6]
One of the solar panels on the first satellite,Arabsat-1A, failed to deploy, resulting in reduced power. This, combined with gyroscope issues, caused it to spend most of its operational lifespan as a reserve satellite.[7]
Fivedirect-to-home television satellites were built using the Spacebus 300 bus, which provided 4.3 kilowatts (5.8 hp) of power.[8]
The Spacebus 2000 series was developed to use additional capacity provided by the Ariane 4. Its solar panels generated 3.5 kilowatts (4.7 hp).[9]
The Spacebus 3000 was introduced around the time theAriane 5 entered service. Spacebus 3000 satellites have masses from 2 to 6 tonnes (2.0 to 5.9 long tons; 2.2 to 6.6 short tons) and produce between 5 and 16 kW. Increasingly largerpayload fairings allowed larger spacecraft to be produced. In 1991,Aérospatiale,Alenia andSpace Systems/Loral joined to form the Satellite Alliance.[5]
The first version of the Spacebus 3000 was the Spacebus 3000A, originally developed for Arabsat.[10] They were also ordered byShin Satellite ofThailand and China'sSino Satellite Communications Company.[11]
Twelve 3000B2 satellites were ordered, five of them byEutelsat for theirW Series, one of which later becameEutelsat 28A. A sixth order from Eutelsat was forEutelsat 8 West A.Nordic Satellite AB, aScandinavian company that later becameSES Sirius, orderedSirius 2, a replacement for the Spacebus 300-based TeleX satellite. Spanish satellite operatorHispasat ordered two satellites, and Arabsat ordered one satellite,Arabsat-3A. The final two were ordered by the GermanBundeswehr and were launched on 1 October 2009,[12] and in May 2010, respectively.[13]
Nine B3 satellites were ordered, three for Eutelsat, two forStar One of Brazil,GE-12 for GE Americom,Turksat 2A for Turksat, and theStentor experimental communications satellite forCNES. Stentor was lost in a launch failure on the maiden flight of theAriane 5ECA. Galaxy 17 was successfully launched in 2007 for Intelsat.[11]
The Spacebus 4000 series was derived from the 3000 series[14] but featured upgradedavionics. Thevoltage of the electrical system was increased from 50 volts to 100 volts, and an integrated onboard computer, designed to be more flexible than previous versions, was added. It was also the first satellite bus to be equipped with anattitude and orbit control system withstar trackers designed for use in geostationary orbit.[14]
The B series used the same basic structure as the 3000 series. The C version had a base measuring 2.2 by 2.0 metres (7.2 ft × 6.6 ft).[citation needed]
Eight Spacebus 4000B2 satellites have been ordered:Bangabandhu-1 for Bangabandhu-1 ofBangladesh,Turksat 3A for Turksat,Thor 6 forTelenor of Norway,Nilesat 201 forNilesat ofEgypt,[15] Athena-Fidus for the French and Italian space agencies CNES andASI,[16] and Sicral-2 for the Italian Ministry of Defence and the French Defence Procurement Agency (DGA), a contract worth about €295m in total,[17] Koreasat-5A and Koreasat-7 for KTSAT and Telkom-3S for PT Telkom Indonesia.[18]
Spacebus 4000B3 satellites are 3.7 metres (12 ft) in height and generate 8.5 kilowatts of power. So far, five have been ordered, including two for the FrenchDélégation Générale pour l'Armement and two forRascomStar-QAF.[19]
The fifth,Palapa D1 forIndosat, uses the ITAR-free configuration, and was launched by a Long March 3B in September 2009, but was initially placed in a low orbit.[20]Thales Alenia Space made corrections allowing the satellite to reach the plannedgeostationary transfer orbit on 3 September.[21] It finally reachedgeostationary orbit on 9 September.[22] It is now undergoing on-orbit testing upon its arrival at 113° East about mid-September, where it will be used to provide communications to Asia and Australia. It has enough fuel for 10 years of service, according toReynald Seznec, President of Thales Alenia Space, instead of the planned 15 years due to the orbit-raising maneuvers.[23][24]
The first Rascom satellite,Rascom-QAF1, suffered a propulsion system failure during its first apogee manoeuvre on 21 December 2007. It was confirmed to have reached its final geostationary orbit at a longitude of 2.85° east on 4 February 2008, but with only two years of expected operational life, compared to the fifteen expected prior to launch.[25] On 9 September 2008, theRascom-QAF1R satellite was ordered to replace it, also based on the 4000B3 bus.[26]
The Spacebus 4000C1 has a height of 4 metres (13 ft), and is capable of generating 8.5 kilowatts of electricity. The only C1 to have been ordered so far isKoreasat 5 forKorea Telecom ofSouth Korea. It was launched by aSea LaunchZenit-3SL from theOcean Odyssey platform on the equator, at 03:27 GMT on 22 August 2006.[14]
The Spacebus 4000C2, which has a height of 4.5 metres (15 ft), generates 10.5 kilowatts of power. Five have been ordered, all using the ITAR-free option, by companies in thePeople's Republic of China.Chinasat, a state-owned company ordered two satellites, whilst theAPT Satellite ordered three.[27] All were launched by Long March 3B rockets fromLaunch Area 2 at theXichang Satellite Launch Centre.[14]
Eight Spacebus 4000C3 satellites, each of which has a height of 5.1 metres (17 ft) and generates 13 kilowatts of power, have been ordered. SES Americom and Eutelsat ordered two spacecraft each.[28][29] The Eutelsat spacecraft are being built using ITAR-free parts, and one of the satellites,Eutelsat W3B launched on an Ariane 5 on 2010-10-28 and was declared lost on 2010-10-30 due to a fuel leak.[30] Eutelsat 21B was ordered by 9 June 2010.;[31] and launched 10 November 2012;[32] Eutelsat W3D ordered on 3 December 2010;,[33] launched 2013-05-14;[34] Russian satellite operatorGazprom also ordered two satellites for itsYamal (satellite constellation) programme[35]—the first time it had procured Yamal spacecraft that were not manufactured in Russia. Only one will be a Spacebus, the second one is based on an Express-2000 platform.[36]
The Spacebus 4000C4 bus is 5.5 metres (18 ft) high and can generate 16 kilowatts of power with its solar panels. Four have been ordered so far:Ciel 2 forCiel Satellite of Canada, which was launched on 10 December 2008,[37] and three spacecraft for Eutelsat,W2A,[38]W7, launched byProton on 23 November 2009.[14] and Eutelsat-8 West B, ordered on 11 October 2012.[39]
On 6 December 2007, Thales Alenia Space signed an agreement withNPO PM of Russia to jointly develop the Ekspress-4000 bus, based on the Spacebus 4000.[40] The Ekspress-4000 is designed for direct injection into geostationary orbit by aProton-M rocket.
In 2014,Thales Alenia Space started the development of a new family - Spacebus NEO. These new platforms will be available in various propulsion versions, including an all-electric one. The all-electric Spacebus NEO, capable of carrying payloads weighing over 1,400 kg, and with power exceeding 16 kW, will be available starting in mid-2015.[41]
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