Astra 1K
Mission typeCommunications
COSPAR ID2002-053A Edit this at Wikidata
SATCAT no.27557
Mission duration15 years (planned)
Failed on orbit (DM03 failure)
Spacecraft properties
Spacecraft typeSpacebus
ManufacturerAlcatel Space
Launch mass5,250 kg (11,570 lb)
Power13 kW
Start of mission
Launch date25 November 2002,
23:04:23 UTC
RocketProton-K / DM03
Launch siteBaikonur, Site 81/23
ContractorKhrunichev State Research and Production Space Center
Entered serviceFailed on orbit (DM03 failure)
End of mission
Decay date10 December 2002
Orbital parameters
Reference systemGeocentric orbit[1]
RegimeLow Earth orbit
Geostationary orbit (planned)
Longitude19.2° East (planned)
Perigee altitude142 km (88 mi)
Apogee altitude288 km (179 mi)
Period88.79 minutes
Band54 transponders:
52 Ku-band
2 Ka-band
Coverage areaEurope

Astra 1K was a communications satellite manufactured by Alcatel Space for SES. When it was launched on 25 November 2002, it was the largest civilian communications satellite ever launched, with a mass of 5,250 kg (11,570 lb).[2] Intended to replace the Astra 1B satellite and provide backup for 1A, 1C and 1D at the Astra 19.2°E orbital position,[3] the Blok DM3 upper stage of the Proton-K launch vehicle failed to function properly, leaving the satellite in an unusable parking orbit.


Astra 1K was to be a European (Luxembourg-based) geostationary communications satellite that was launched by a Proton-K launch vehicle from Baikonur Cosmodrome at 23:04:23 UTC on 25 November 2002. However, the Blok DM3 upper stage attached to the 5,250 kg (11,570 lb), 13 kW satellite (reported to be the most massive of civilian communications satellite, with its 52 Ku-band and two Ka-band transponders to cover 1,100 channels) was miscommanded to separate after the first burn, resulting in the satellite orbiting at a very low orbit. In an effort to prevent imminent re-entry, the satellite was raised to a circular orbit at an altitude of 288 km, providing sufficient time to select the best course of action. Three options were then under consideration: a) to force its re-entry over the Pacific Ocean, b) to retrieve it by a Space Shuttle, and c) to use up all the fuel on board the satellite to move it to a geostationary orbit at 19.2° east.[4] Although it was suggested that a separately-launched Orbital Recovery Corporation 'space tug' (then in development) might be used to take the satellite to geostationary orbit,[5] the decision was taken in December 2002 to deorbit the satellite, resulting in a huge insurance loss and bringing into question both continued use of the Blok D series of upper stages and the "bigger is better" communications satellite philosophy.[6][2] Astra 1K was intentionally de-orbited on 10 December 2002.[7]


The satellite featured frequency re-use for some of its transponders, using dual patterns coverage, one covering eastern Europe, the other covering Spain. This design was meant to cover specific markets only, in order to expand the capacity of the fleet, as frequency re-use enables more channels to be transmitted simultaneously at the same frequency, with the drawback that channels broadcast on the Spain beam wouldn't be receivable by any means (no matter how large the receiving dish would be) in the east beam and vice versa. This would have left for example the Netherlands and parts of neighbouring countries without reception of either of the beams, as the beams overlap over those countries, efficiently jamming each other.

Astra 1K also featured multiple Ka-Band capabilities, originally intended to provide an upload path for satellite Internet access services. SES later developed such a 2-way commercial satellite internet service with ASTRA2Connect (now SES Broadband), using Ku-band for upload and download paths.[8]

Replacement satellite

A replacement satellite, Astra 1KR was successfully launched in 2006.[9]

See also


  1. ^ "Satellite Catalog". Jonathan's Space Report. Retrieved 9 April 2021.
  2. ^ a b "Proton-K/DM-2M". Encyclopedia Astronautica. 2019. Archived from the original on 20 August 2016. Retrieved 9 April 2021.
  3. ^ "ASTRA 1K UNDER PROCUREMENT WITH AÉROSPATIALE" (Press release). SES ASTRA. 11 February 1998. Retrieved 26 January 2012.
  4. ^ "Display:Astra 1K 2002-053A". NASA. 10 February 2021. Retrieved 9 April 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  5. ^ Orbital Recovery Corporation Offers Space Rescue for Stranded Astra 1K Telecommunications Satellite Space Ref. 5 December 2002. Accessed 27 January 2023
  6. ^ Satellite loss likely despite recovery efforts Business Insurance. 2 December 2002. Accessed 27 January 2023
  7. ^ "ASTRA 1K - Satellite Informations". Retrieved 9 April 2021.
  9. ^ "ASTRA 1KR SATELLITE SUCCESSFULLY LAUNCHED" (Press release). SES ASTRA. 21 April 2006. Retrieved 26 January 2012.