Sirius (satellite)

Sirius is a constellation of communications satellites operated in geostationary orbit (GEO) by SES Sirius. They carry digital satellite television to the countries of Scandinavia and Baltic states, including the Viasat pay TV system, along with several pay TV packages for eastern Europe. The satellites also carry a number of Ukrainian channels and the national Latvian and Lithuanian channel service free-to-air.

Satellites

irius 2

Sirius 2 was manufactured by Aérospatiale and launched from Kourou on November 12, 1997 to replace the Tele-X satellite. It is of the model Spacebus 3000B2 and has 32 K_u band transponders with beams targeting both the Nordic region and all of Europe.

It was moved to 31.5°E (coord|0|31.5|display=inline) and renamed Astra 5A on 29 April 2008.

irius 3

Sirius 3 currently operate from 4.8° East (coord|0|4.8|display=inline). Sirius 2 has always operated from 4.8°E, however Sirius 3 was lent to SES Astra at its launch as a backup for Astra 2B at 28.2°E (coord|0|28.2|display=inline), which was believed to be seriously faulty on launch.

irius 4

A fourth satellite, Sirius 4, was ordered in 2005 and launched at 22:39:47 on 17 November 2007. It carries 52 active Ku-band transponders and 2 active Ka-band transponders. [cite web | url = http://www.ilslaunch.com/zmedia/newsarchives/newsreleases/rec203/ | title = ILS Proton to Launch SES' Sirius 4 | publisher = ILS | date = November 9, 2007] Sirius 4 was built by Lockheed Martin Space Systems based upon the A2100AX design. [cite web | url = http://coopi.khrunichev.ru/eng/pl_pusk.htm | title = Sirius-4 Specifications | publisher = Khrunichev]

Among the services carried are Viasat & Viasat Ukraine which has used the Sirius satellites for their digital platform since its launch.

It is expected that Sirius 4 will replace both Sirius 2 and Sirius 3.

Retired satellites

A previous Sirius satellite, Sirius 1 (later Sirius W) was purchased from BSkyB after Sky Television's merger with British Satellite Broadcasting (the merger was conducted on Sky's terms and BSB's satellites were sold in favour of Sky's leased Astra satellite operations). The satellite had previously operated as Marcopolo 1. It operated at 5 East from 1994 until 2000, when it was moved to 13 West. It operated here before being dumped to graveyard orbit in 2003.

The Sirius satellites are not the satellites used for the American Sirius Satellite Radio service, whose satellites are named Radiosat 1-4 due to being launched after the Sirius fleet of satellites.

References

External links

* [http://www.lyngsat.com/sirius.html Transponder lineup]
* [http://www.ssc.se/default.asp?groupid=2004102210358979&pageid=2004102210321971 Sirius 1 info from Swedish Space Corporation]
* [http://www.ssc.se/default.asp?groupid=2004102210358979&pageid=20041022103241513 Sirius 2 info from Swedish Space Corporation]
* [http://www.ssc.se/default.asp?groupid=2004102210358979&pageid=20041022103258782 Sirius 3 info from Swedish Space Corporation]
* [http://www.ses-sirius.com/satellites/sirius-2/ SES Sirius]
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* [http://www.lyngsat.com/sirius2.html Lyngsat]