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Astra 5A

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Astra 5A
NamesSirius 2
GE-1E
Mission typeCommunications
OperatorNordiska Satelit AB / GE Americom / SES Sirius AB / SES Astra
COSPAR ID1997-071A Edit this at Wikidata
SATCAT no.25049
Mission duration15 years (planned)
11 years, 2 months (achieved)
Spacecraft properties
SpacecraftSirius 2
Spacecraft typeSpacebus
BusSpacebus 3000B2
ManufacturerAérospatiale
Launch mass2,920 kg (6,440 lb)
Dry mass1,250 kg (2,760 lb)
Power6.5 kW
Start of mission
Launch date12 November 1997, 21:48 UTC
RocketAriane 44L H10-3 (V102)
Launch siteCentre Spatial Guyanais, ELA-2
ContractorArianespace
Entered serviceJanuary 1998
End of mission
DisposalGraveyard orbit
DeactivatedApril 2009
Last contact16 January 2009
Orbital parameters
Reference systemGeocentric orbit[1]
RegimeGeostationary orbit
LongitudeAstra 5°E (1997-April 2008)
Astra 31.5°E (April 2008-2009)
Transponders
Band32 (+8) Ku-band
Bandwidth26 transponders at 33 MHz
6 transponders at 36 MHz
Coverage areaSweden, Central Europe, Southern Europe, Middle East

Astra 5A was one of the Astra communications satellites owned and operated by SES at the Astra 31.5°E. Launched in 1997 to the 5° East position by NSAB (Nordiska Satelit AB) (later SES Sirius, and now a non-autonomous part of SES) as Sirius 2, operation of the satellite was transferred to SES in April 2008 and the craft renamed and moved to 31.5° East to open up a new orbital position for the company for the development of markets in Central and Eastern Europe and the Middle East.[2]

Astra 5A failed in orbit in 2009.

Sirius 2 / GE-1E

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Sirius 2 is a 32 transponder satellite, used for direct-to-home (DTH) transmissions as well as video and data communication services. Sirius 2 has two DTH beams, each with 13 transponders used for transmission of TV channels to homes equipped with parabolic antennas. One of the beams transmits to the Nordic area and the other towards central and southern Europe. GE AMERICOM, later SES Americom, operates 13 of the transponders in the European beam, originally under the name GE-1E. Sirius 2 has a third beam, for video and data communications. It consists of six 36 MHz transponders and covers northern and central Europe.[3]

Market

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The Astra 5A satellite provided two broadcast beams, of horizontal and vertical polarisation, across two footprints, called the CEE (Central and Eastern European) beam and the PE (pan-European) beam. The CEE beam provides reception on a 60 cm dish from Poland to northern Turkey, and the Balkans to the Black Sea, while the PE beam extends 60 cm coverage from Tunisia to the Urals and from the Baltic states to Israel.[4]

Countries covered include Armenia, Azerbaijan, Belarus, Bosnia, Bulgaria, Czech Republic, Georgia, Hungary, Iran, Jordan, North Macedonia, Moldova, Poland, Romania, Russia, Serbia, Slovakia, Tunisia, Turkey, and Ukraine.[5]

Demise of satellite

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On 16 January 2009, Astra 5A "experienced a technical anomaly leading to the end of the spacecraft's mission".[6] All traffic ceased, with much of it (especially channels for German cable service, Kabel Deutschland) transferred to Astra 28.5° East. Transfer of services to Astra 1D was not practical because this satellite, although effectively co-located with Astra 5A, was in an inclined orbit and usable only for TV contribution services and other intermittent use.

In March 2009, SES Astra announced that in April 2009, the Astra 2C satellite was to be moved from the 28.2° East position to Astra 31.5°E to temporarily take over Astra 5A's mission until Astra 3B was launched to Astra 23.5°E, at which time another craft currently there could be released to 31.5°E.[7] The move of Astra 2C was started in May 2009 and completed on 11 May 2009.[8]

In 2010, Astra 3B came into service at Astra 23.5°E and Astra 1G was moved from that position to Astra 31.5°E to take over all broadcasting activity from Astra 2C, which was moved to Astra 19.2°E in September 2010.

In December 2013, it is expected that a new satellite, Astra 5B will be launched to the Astra 31.5°E position to permanently take over all broadcasting from this position.[9]

After the loss of Astra 5A's Sun sensors (used to orient towards the Sun to charge the craft's batteries) the batteries quickly depleted rendering it impossible to send control information to the satellite. Collisions were a possibility, with Intelsat 802 stated the most probable.[10] In April 2009, SES Astra said that they had managed to regain control of the satellite and that it had been moved out of geostationary orbit, into a higher one, presumably a graveyard orbit.[11][12]

See also

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References

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  1. ^ "SIRIUS 2 (GE-1E) 1997-071A 25049". N2YO.com. Retrieved 6 April 2021.
  2. ^ "SES ASTRA STARTS NEW ORBITAL POSITION AT 31.5 DEGREES EAST" (Press release). SES ASTRA. 29 April 2008. Retrieved 26 January 2012.
  3. ^ "Sirius 2 (GE 1E) / Astra 5A". Gunter's Space Page. 11 December 2017. Retrieved 6 April 2021.
  4. ^ "Astra 5A Factsheet". SES ASTRA. Archived from the original on 1 August 2008. Retrieved 22 September 2008.
  5. ^ SES ASTRA "31.5° East" (August 2007) Company factsheet
  6. ^ "SES ASTRA Announces End Of ASTRA 5A Spacecraft Mission" (Press release). SES ASTRA. 16 January 2009. Retrieved 26 January 2012.
  7. ^ "SES To Move ASTRA 2C Satellite To 31.5 Degrees East To Support Development Of New Orbital Position" (Press release). SES Astra. 10 March 2009. Retrieved 26 January 2012.
  8. ^ Astra 2C arrived at 31.5 East LyngSat, Retrieved 1 June 2009
  9. ^ "Astra 5B 31.5° East" (PDF). SES.com. 1 November 2013. Archived from the original (PDF) on 1 November 2013. Retrieved 6 April 2021.
  10. ^ "Failed Telecommunications Satellite Drifts Out of Control". Space.com. 23 January 2009.
  11. ^ "End of the road for Astra 5A". 16 April 2009.
  12. ^ "SES Astra switches off Astra 5A satellite". Media Network. 17 April 2009. Archived from the original on 27 July 2011. Retrieved 6 April 2021.
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