Astra 5A

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Astra 5A (Sirius 2)
COSPAR ID 1997-071A
SATCAT № 25049
Mission duration 15 years
Spacecraft properties
Bus Spacebus 3000
Manufacturer Aérospatiale
Launch mass 2,920 kilograms (6,440 lb)
Power 6,500 watts
Start of mission
Launch date November 12, 1997 (1997-11-12)
Rocket Ariane 44L V102
Launch site Kourou ELA-2
Contractor Arianespace
End of mission
Disposal Decommissioned
Deactivated April 2009 (2009-05)
Orbital parameters
Reference system Geocentric
Regime Geostationary
Longitude 5° East
31.5° East
Perigee 36,018 kilometres (22,381 mi)[1]
Apogee 36,059 kilometres (22,406 mi)[1]
Inclination 4.51 degrees[1]
Period 1448.71 minutes[1]
Epoch 3 April 2014, 08:51:14 UTC[1]
Transponders
Band 32 Ku band
Bandwidth 33 megahertz
TWTA power (PE beam) 85 watts
(CEE Beam) 57 watts
EIRP 51 decibel-watts

Astra 5A was one of the Astra communications satellites owned and operated by SES at the Astra 31.5°E orbital slot. Launched in 1997 to the 5°E position by NSAB (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°E to open up a new orbital position for the company for the development of markets in Eastern Europe and the Middle East.[2]

Astra 5A failed in orbit in 2009.

Market[edit]

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.[3]

Countries covered include Armenia, Azerbaijan, Belarus, Bosnia, Bulgaria, Czech Republic, Georgia, Hungary, Iran, Jordan, Macedonia, Moldova, Poland, Romania, Russia, Serbia, Slovakia, Tunisia, Turkey, and Ukraine.[4]

Demise of satellite[edit]

On January 16, 2009 Astra 5A "experienced a technical anomaly leading to the end of the spacecraft's mission".[5] All traffic ceased, with much of it (especially channels for German cable service, Kabel Deutschland) transferred to Astra 23.5°E.

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 announced that in April, 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.[6] The move of Astra 2C was started in May 2009 and completed on May 11.[7]

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.[8]

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.[9] In April 2009 SES 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.[10][11]

See also[edit]

References[edit]

  1. ^ a b c d e "SIRIUS 2 (GE-1E) Satellite details 1997-071A NORAD 25049". N2YO. 3 April 2014. Retrieved 5 April 2014. 
  2. ^ "SES ASTRA STARTS NEW ORBITAL POSITION AT 31.5 DEGREES EAST" (Press release). SES ASTRA. April 29, 2008. Retrieved January 26, 2012 . 
  3. ^ "Astra 5A Factsheet". SES ASTRA. Archived from the original on August 1, 2008. Retrieved September 22, 2008. 
  4. ^ SES ASTRA "31.5° East" (August, 2007). Company factsheet
  5. ^ "SES ASTRA Announces End Of ASTRA 5A Spacecraft Mission" (Press release). SES ASTRA. January 16, 2009. Retrieved January 26, 2012 . 
  6. ^ "SES To Move ASTRA 2C Satellite To 31.5 Degrees East To Support Development Of New Orbital Position" (Press release). SES Astra. March 10, 2009. Retrieved January 26, 2012 . 
  7. ^ Astra 2C arrived at 31.5 East. LyngSat. Retrieved June 1, 2009
  8. ^ "Astra 5B Factsheet". SES. Retrieved November 1, 2013. 
  9. ^ http://www.space.com/missionlaunches/090120-dead-satellite-loses-control.html
  10. ^ http://www.broadbandtvnews.com/2009/04/16/end-of-the-road-for-astra-5a/
  11. ^ http://blogs.rnw.nl/medianetwork/ses-astra-switches-off-astra-5a-satellite

External links[edit]