SES Astra explained

Company Name:SES ASTRA
Company Type:Privately-owned subsidiary
Foundation:1985
Location: Betzdorf, Luxembourg
Industry:Telecommunications
Products:Satellite Services
Revenue: ? billion (2006)
Net Income: ? billion (2006)
Operating Income: ? billion (2006)
Num Employees:368 (2007)
Parent:SES
Subsid:SES ASTRA TechCom
Homepage:SES ASTRA

SES Astra SA, is a corporate subsidiary of SES, based in Betzdorf, in eastern Luxembourg, that owns and operates the Astra series of geostationary communication satellites, which transmit approximately 2300 analogue and digital television and radio channels via 242 transponders to 109 million households across Europe.[1]

Formed in 1985 as Société Européenne des Satellites (SES), it was Europe's first private satellite operator. Its slogan is currently "Your Satellite Connection to the World".

The first customer of SES Astra was Sky Television which leased four transponders on Astra 1A ahead of its launch in 1989. UK and Ireland-aimed channels ceased at 19.2°East in September 2001 with the closure of Sky's analogue service, although their digital service has been the main occupier of Astra's secondary position at 28.2°East since its launch in 1998.

Satellite details

SES Astra operates 15 satellites from five orbital locations - Astra 19.2°E, Astra 28.2°E, Astra 23.5°E, Astra 5°E, Astra 31.5°E. Astra's principle of "co-location" (several satellites are close to each other, all within a cube with a size of 150 km[2] ); this increases flexibility and redundancy.

SatelliteLaunch DateManufacturerModelLaunch vehicleComments
ASTRA 19.2°E
1FApril 8 1996HughesHS-601Proton-K
1HJune 16 1999HughesHS-601HPProton
1KR20 April 2006Lockheed MartinA2100Atlas V (411)Launched after the failure of Astra 1K.
1LMay 4, 2007Lockheed MartinA2100Ariane 5-ECAReplacement for 1E/2C; Ku and Ka bands
1MNov 6, 2008EADS AstriumEurostar E3000Proton-MTo replace 1G and provide backup at 19.2° East. Ready for commercial service 20 January 2009[3]
ASTRA 28.2°E
2AAugust 30 1998HughesHS-601HPProton
2BSeptember 14 2000AstriumEurostar E2000+Ariane 5G
2CJune 16 2001HughesHS-601HPProtonInitially deployed at 19.2° East pending launch of 1L, then moved to originally intended position of 28.2° East, with 2A, 2B and 2D
2DDecember 19 2000HughesHS-376HPAriane 5G
ASTRA 23.5°E
3AMarch 29 2002BoeingHS-376HPAriane 44L
1EOctober 19 1995HughesHS-601Ariane 42LMoved from 19.2° East to 23.5° East to provide additional capacity alongside Astra 4A for central and eastern Europe.
1GDecember 2 1997HughesHS-601HPProton-KPower problems, now max 20 transponders. Moved from 19.2° east February 2009 following launch of Astra 1M
ASTRA 5°E
4ANovember 18 2007Lockheed MartinA2100AXProton-MLeased transponders of Sirius 4, marketed as Astra 4A
1CMay 12 1993HughesHS-601Ariane 42LMoved from 19.2° East to 5° East to provide occasional capacity alongside Astra 4A. In inclined orbit
ASTRA 31.5°E
1DNovember 1 1994HughesHS-601Ariane 42POriginally at 19.2° East; used at 28.2° East and 23.5° East. Moved to 31.5° East to provide occasional capacity alongside Astra 5A (now failed) for central and eastern Europe and Russia. In inclined orbit
NO LONGER IN OPERATION
1ADecember 11 1988GE AstroSpaceGE-4000Ariane 44LPThe first Astra satellite. Now retired in graveyard orbit.
1BMarch 2 1991GE AstroSpaceGE-5000Ariane 44LPAcquired from GE Americom (Satcom K3). Now retired in graveyard orbit.
1KNovember 26 2002Alcatel SpaceSpacebus 3000B3SProtonLaunched to 19.2° East but failed to reach geostationary orbit, and intentionally de-orbited on December 10, 2002.
5ANovember 12 1997Alcatel SpaceSpacebus-3000B2Ariane 44LFormerly known as Sirius 2. Moved to 31.5° East and renamed Astra 5A on April 29, 2008. Failed in-orbit January 16, 2009
NOW IN CONSTRUCTION
3BDue end 2009EADS AstriumEurostar E3000Ariane 5-ECATo replace all capacity at 23.5° East. 52 transponders in Ku band and 4 in Ka band
1NDue 2011EADS AstriumEurostar E3000To replace 1H and provide backup at 19.2° East
Notes
  1. 19.2° East is the most common orbital position for direct-to-home satellite TV and radio transmission in Germany, Western and Central Europe.
  2. British Sky Broadcasting broadcast their Sky Digital direct-to-home television service to the United Kingdom and Republic of Ireland from the 28.2° East satellite constellation. Eutelsat's Eurobird 1 satellite also operates close to this position.

Satellite manufacturer and launch

SES Astra operates satellites designed by Boeing Satellite Systems or BSS (formerly Hughes Space and Communications), EADS Astrium, Alcatel Space, and Lockheed Martin.

Astra satellites within a family are not identical, for example of the Astra 2 satellites; 2A and 2C are BSS 601HPs, 2B is an Astrium Eurostar-2000 and 2D is a BSS 376.

The satellites are launched by Arianespace rockets from Kourou, French Guiana or International Launch Services Proton rockets from Baikonur, Kazakhstan. The satellites are launched into an elliptical "temporary transfer orbit" from where they use onboard propulsion to reach their final circular geostationary orbits, at nearly 36,000 km altitude. Proton rockets fitted with a fourth stage propulsion unit are capable of launching the satellites several thousand kilometres higher (at the closest point of the elliptical orbit) than Ariane rockets. As a result most satellites launched in this way have to use less fuel to reach their geostationary orbit, increasing their lifetime.

Failures

Astra 1K, the largest commercial communications satellite ever built at the time, was ordered by SES-Astra in 1997. It was launched by Proton rocket on November 26 2002. The rocket lifted off as planned and reached its parking orbit at which point the final stage of the rocket was to initiate a second burn to transfer the satellite to its geostationary orbit. This did not occur and the satellite was released into the parking orbit, making it unusable. The only way to recover the satellite would have been the use of a Space Shuttle, however this was rejected. On December 10 2002 SES Astra instructed Alcatel Space (the manufacturer) and the French Space Agency CNES to deorbit the satellite, it broke up on re-entry over the Pacific Ocean.

On January 16, 2009 Astra 5A "experienced a technical anomaly leading to the end of the spacecraft’s mission"[4] some four years ahead of the spacecraft's expected end of life. Traffic carried by the satellite (especially channels for German cable service, Kabel Deutschland) was transferred to Astra 23.5°E. The Swedish Space Corporation (technical operators of the craft) and SES Astra are investigating the failure and working to de-orbit the satellite. Future deployment of satellite(s) to the Astra 31.5°E position is yet to be decided.

See also

External links

Notes and References

  1. SES. February 18, 2008. SES REPORTS ANOTHER YEAR OF STRONG FINANCIAL PERFORMANCE.
  2. http://www.ses.com/ses/PDFs/Investor_Relations/InvestorDays_2006/Investor_Day_2006SatTechno.pdf Satellite technology
  3. SES ASTRA. January 20, 2009. New ASTRA 1M Satellite Ready For Operation.
  4. SES ASTRA. January 16, 2009. SES ASTRA Announces End Of ASTRA 5A Spacecraft Mission.