Astra 1K

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Astra 1K
Mission type Communications
Operator SES Astra
COSPAR ID 2002-053A
SATCAT № 27557
Mission duration None (Launch failure)
Spacecraft properties
Bus Spacebus-3000B3S
Manufacturer Alcatel Space
Launch mass 5,250 kilograms (11,570 lb)
Power 13,000 watts
Start of mission
Launch date 25 November 2002, 23:04:23 (2002-11-25UTC23:04:23Z) UTC
Rocket Proton-K/DM3
Launch site Baikonur 81/23
Contractor International Launch Services
End of mission
Disposal Deorbited
Decay date 10 December 2002 (2002-12-11)
Orbital parameters
Reference system Geocentric
Regime Low Earth
Geostationary planned
Longitude 19.2° east (planned)
Slot Astra 1
Perigee 142 kilometres (88 mi)
Apogee 287 kilometres (178 mi)
Inclination 51.5 degrees
Period 88.79 minutes
Epoch 27 November 2002[1]
Transponders
Band 52 Ku-band
2 Ka-band

Astra 1K was a communications satellite manufactured by Alcatel Space for SES. When it was launched on November 25, 2002 it was the largest civilian communications satellite ever launched, with a mass of 5,250 kilograms (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 launch vehicle failed to function properly, leaving the satellite in an unusable parking orbit. Although some attempts were made to "rescue" the satellite,[4] it was intentionally de-orbited on December 10, 2002.[5]

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 services. SES later developed such a 2-way commercial satellite internet service with ASTRA2Connect, using Ku band for upload and download paths.[6]

A replacement craft, Astra 1KR was successfully launched in 2006.[7]

See also[edit]

References[edit]

  1. ^ McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page. Retrieved 27 September 2013. 
  2. ^ "Proton 8K82K / 11S861-01". Encyclopedia Astronautica. 
  3. ^ "ASTRA 1K UNDER PROCUREMENT WITH AÉROSPATIALE" (Press release). SES ASTRA. February 11, 1998. Retrieved January 26, 2012. 
  4. ^ "ASTRA 1K satellite stabilised" (Press release). SES ASTRA. November 28, 2002. Retrieved January 26, 2012. 
  5. ^ ASTRA 1K - Satellite Information, accessed 2013-09-27
  6. ^ "SES TO DEVELOP INTERACTIVE SATELLITE RETURN CHANNEL" (Press release). SES ASTRA. December 15, 1998. 
  7. ^ "ASTRA 1KR SATELLITE SUCCESSFULLY LAUNCHED" (Press release). SES ASTRA. April 21, 2006. Retrieved January 26, 2012. 

External links[edit]