Thor (satellite)

Summary

Thor (previously known as Marcopolo) is a family of satellites designed, launched and tested by Hughes Space and Communications (now part of Boeing Satellite Systems) for British Satellite Broadcasting (BSB), and were used for Britain's Direct Broadcast Service. Thor is owned by Telenor.[1] Marcopolo 1 launched on 27 August 1989 on the 187th launch of a Delta rocket, and Marcopolo 2 launched on 17 August 1990, on a Delta II rocket.[2] Marcopolo I had the Hughes designation HS376.[3]

Although the satellites performed as designed, BSB[4] merged with Sky Television to form British Sky Broadcasting and the BSB satellites were sold off and renamed. This also resulted in the obsoletion of the Squarial satellite-reception antenna, which was designed to operate with Thor 1 only.

Marcopolo 1 (Sirius 1/Sirius W) edit

Sirius W, previously known as Sirius 1, was launched on 27 August 1989. It was Hughes Space and Communications's first satellite. Marcopolo 1 was sold in December 1993 to Nordic Satellite AB of Sweden and operated until 2000 as Sirius 1 at 5°E. It was then moved to 13°W, and renamed Sirius W. It had 5 Ku band transponders.

Marcopolo 2 (Thor 1) edit

Marcopolo 2 was launched on 18 August 1990. It had 5 Ku band transponders. It was sold in July 1992 to Telenor of Norway and renamed Thor 1. It was located at 0.8°W. It was switched off in January 2002, and in November of that year it was moved to 7.4°W and reactivated with digital test signals broadcasting toward Scandinavia. Marcopolo 2 was sent up to the junk orbit in early January 2003.

Thor 2 edit

Thor 2 was launched on 21 May 1997, and retired in 2008 although it remained in an inclined geostationary orbit until January 2013 when it de-orbited to the graveyard orbit.[5] It weighs 1467 kg, and has 15 Ku band transponders, with 3 spares, powered by 40-watt traveling-wave tube amplifiers (TWTAs).

Thor 3 edit

Thor 3 (the "3" is officially "III") was a satellite used by Canal Digital in the Nordic areas for DTH services. It launched on 9 June 1998 with an expected lifetime at 12 years, and was located at 0.8°W. It had 14 active Ku band transponders powered by 47-watt traveling-wave tube amplifiers (TWTAs). The satellite was targeted on Scandinavia, Eastern Europe, and parts of Central Europe.[6] Thor 3 is no longer in operation and was moved to its graveyard orbit in 2019. Thor 3 was replaced by Thor 6 in June 2010.

Intelsat 10-02 (Thor 10-02) edit

Intelsat 10-02 was launched on 16 June 2004, located at 1°W, and was beamed toward Central Europe and the Middle East.[7]

Thor 5 edit

Thor 5 was launched on 11 February 2008. It was first planned that the satellite would be called Thor 2R', but Telenor named it Thor 5. It has 24 active Ku band transponders.

Thor 6 edit

Thor 6 was launched from the Guiana Spaceport on 29 October 2009.[8] Telenor Satellite Broadcasting announced on 15 December that Thor 6 had completed all necessary in-orbit and ground-related testing and would commence commercial service in late December.

Thor 6 has 36 Ku band transponders. It provides direct-to-home television broadcasting services from the orbital location 0.8°W. It replaced Thor 3.[9]

Thor 7 edit

Thor 7 has been built by SSL. It was successfully launched by Arianespace from Kourou spaceport on 26 April 2015. It will mainly serve maritime customers and have a total capacity of 9 Gbit/s. It was launched in tandem with the Italian/French Sicral 2 defense satellite.

References edit

  1. ^ BSB History by Boeing Archived 20 January 2009 at the Wayback Machine
  2. ^ "Boeing Launch Services Mission Record". Boeing.
  3. ^ Krebs, Gunter D. "Marco Polo 1, 2 (BSB 1, 2) / Sirius 1 / Thor 1"". Gunter's Space Page. Retrieved 16 January 2023.
  4. ^ "TSE - BSB 1". www.tbs-satellite.com.
  5. ^ Clover, Julian (14 January 2013). "Thor II de-orbited after 15 years". Broadband TV News. Retrieved 14 January 2013.
  6. ^ Krebs, Gunter D. "Thor 2, 3". Gunter's Space Page. Retrieved 16 January 2023.
  7. ^ Ray, Justin (17 June 2004). "Powerful broadcasting satellite goes into orbit". Spaceflight Now.
  8. ^ "Mission accomplished! Arianespace orbits NSS-12 and THOR 6 34th successful Ariane 5 launch in a row". Arianespace Group. 29 October 2009. Retrieved 16 January 2023.
  9. ^ "Thor 6 (Intelsat 1W, IS-1W)". Satbeams.com. Retrieved 16 January 2023.

External links edit

  • Thor 3 coverage map
  • Thor 4 (Intelsat 10-02) coverage map
  • Thor 5 coverage map
  • Thor 6 coverage map
  • Thor 7 coverage map