SES Astra

Şablon:Infobox Company SES Astra SA, bir SES yan kuruluşudur. Yeri Doğu Lüksemburg, Betzdorf'tadır. Hizmet verdiği Avrupa'da 91 milyon ev halkına, 176 transponder yolu ile yaklaşık 1100 dijital radyo ve televizyon yayınını ulaştıran Astra iletişim uydularını çalıştırır.

1985'te (Société Européenne des Satellites) (SES) olarak kuruldu ve Avrupa'nın ilk özel uydu operatörüydü. Sloganı ise, "Dünya senin uydu bağlantındır".

SES Astra'nın ilk müşterisi BSkyB'dir. 1989 yılında Astra 1A'da 4 adet transponder kiralamıştır.

Uydu detayları

SES Astra beş ayrı yörüngeden toplam 15 uyduyu işletmektedir. Bu uydular Astra-19.2 ° E, Astra-28.2 ° E, Astra-23.5 ° E, Astra-5 ° E, Astra-31.5 ° E'dır. Ortak yörünge Astra'nın ilkesidir. (Aynı yörüngede birden fazla uydu)

Uydu	Pozisyon	İlk ayak izi	Yüklenici	Model	Fırlatılış	Fırlatılış aracı
1A	Servis Dışı (Aralık 2004)		GE AstroSpace	GE-4000	11 Aralık 1988	Ariane 44LP
1B	Servis Dışı (Temmuz 2006)		GE AstroSpace	GE-5000	2 Mart 1991	Ariane 44LP
1C	5°E		Hughes	HS-601	12 Mayıs 1993	Ariane 42L
1D	31.5°E		Hughes	HS-601	1 Kasım 1994	Ariane 42P
1E	19.2°E		Hughes	HS-601	19 Ekim 1995	Ariane 42L
1F	19.2°E		Hughes	HS-601	8 Nisan 1996	Proton
1G	19.2°E		Hughes	HS-601HP	2 Aralık 1997	Proton
1H	19.2°E		Hughes	HS-601HP	16 Haziran 1999	Proton
1K	19.2°E	Failed to reach orbit	Alcatel Space	Spacebus 3000B3S	Kasım 26 2002	Proton	Rocket failure, ditched in Pacific Ocean.
1KR	19.2°E		Lockheed Martin	A2100	20 Nisan 2006	Atlas V	Launched after the failure of the Astra 1K.
1L	19.2°E		Lockheed Martin	A2100	Mayıs 4, 2007	Ariane 5-ECA	Replacement for 1E/2C; Ku and Ka bands
1M	19.2°E	Under construction	EADS Astrium	Eurostar E3000	Due 2008		To replace 1H and provide backup at 19.2°E
1N	19.2°E	Under construction	EADS Astrium	Eurostar E3000	Due 2011		To replace 1G and provide backup at 19.2°E
2A	28.2°E		Hughes	HS-601HP	Ağustos 30 1998	Proton
2B	28.2°E		Astrium	Eurostar E2000+	Eylül 14 2000	Ariane 5
2C	28.2°E		Hughes	HS-601HP	Haziran 16 2001	Proton	Initially deployed at 19.2°E pending launch of 1L, then moved to originally intended position of 28.2°E, with 2A, 2B and 2D
2D	28.2°E		Hughes	HS-376HP	Aralık 19 2000	Ariane 5
3A	23.5°E		Boeing	HS-376HP	Mart 29 2002	Ariane 44L
3B	23.5°E	Under construction	EADS Astrium	Eurostar E3000	Due end 2009		to replace Astra 1E; 52 transponders both in Ku and Ka bands
4A	5°E		Lockheed Martin	A2100AX	Kasım 18 2007	Proton M	Leased transponders of Sirius 4, marketed as Astra 4A
5A	31.5°E		Alcatel Space	Spacebus-3000B2	Kasım 12 1997		Formerly known as Sirius 2. Moved to 31.5°E and renamed Astra 5A on 29 April 2008

Notlar

1. 19.2°E is the most common orbital position for direct-to-home satellite TV and radio transmission in Germany, Western and Central Europe.
2. BSkyB broadcast their Sky Digital direct-to-home television service to the United Kingdom and Republic of Ireland from the 28.2°E satellite constellation. Eutelsat's Eurobird 1 satellite also operates close to this position.

Satellite manufacturer & 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.

See also

• SES S.A.
• Astra 19.2°E
• Astra 28.2°E
• Astra 5°E
• Astra 23.5°E
• Astra 31.5°E
• List of broadcast satellites
• Astra Digital Radio
• ASTRA2Connect
• SES Sirius
• SES New Skies
• SES Americom
• SES ASTRA TechCom

Dış bağlantılar

• SES Astra - Resmi web sayfası
• SES Astra interaktif uydu filo haritası
• SES Astra TechCom - Resmi web sayfası