Ekspress AM4

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Ekspress AM4
Mission type Communications
Operator FGUP
COSPAR ID 2011-045A
SATCAT № 37798
Mission duration 15 years planned
Launch failure
Spacecraft properties
Bus EADS Astrium
Manufacturer Eurostar-3000
Launch mass 5,775 kilograms (12,732 lb)
Power 14 kilowatts
Start of mission
Launch date 17 August 2011, 21:25:01 (2011-08-17UTC21:25:01Z) UTC[1]
Rocket Proton-M/Briz-M
Launch site Baikonur 200/39
Contractor Khrunichev
End of mission
Disposal Deorbited
Decay date 25 March 2012 (2012-03-26)
Orbital parameters
Reference system Geocentric
Regime Medium Earth
Geostationary planned
Longitude 80° east planned
Perigee 695 kilometres (432 mi)
Apogee 20,239 kilometres (12,576 mi)
Inclination 51.1 degrees
Period 6.04 hours
Epoch 25 August 2011[2]

Ekspress AM4 was a communications satellite placed into the wrong orbit from a faulty Briz-M rocket stage. This satellite was to be part of the Ekspress series of geostationary communications satellites owned by Russian State Company for Satellite Communications. The satellite was de-orbited on 28 March 2012 into the Pacific Ocean, in spite of efforts of it being used for Antarctic broadband purposes.[3]

Although there have been several satellites de-orbited over the years, Ekspress AM4 would have been able to provide broadband services to the Antarctic for the first time.[4]

Launch[edit]

The Ekspress AM4 satellite was launched on the 18 August 2011 on a Russian Proton rocket from Kazakhstan, which included a Briz-M stage. It was just after launch that the Briz-M stage did not separate from the Ekspress satellite, causing it to fall into the wrong orbit.[5]

Spacecraft[edit]

The total mass of the Ekspress AM4 satellite was 5,800 kg, and the spacecraft had 64 transponders. The onboard antennas were capable of broadcasting in the C, Ku, L, and Ka bands. The satellite's orbit was measured at 1,007 by 20,317 km altitude, with an inclination orbit of 51.3 degrees. Though the satellite was placed in the wrong orbit, there was no damage to the satellite, meaning that it became the subject of numerous reuse proposals.

Reuse proposals[edit]

One of the most notable[citation needed] reuse proposals came from a company called Polar Broadband Systems, which was established in December 2011. Its objectives were to submit proposals for the reuse of semi-retired and retired satellites for use with communications over the Antarctic. The company notes that it would not have been feasible to build a dedicated satellite for the region as the population would not justify the expense, however Ekspress AM4 would suffice as it could have been maneuvered into the required orbit. There was enough fuel on board for it to be operational for ten years, with giving the Antarctic region 16 hours of broadband access a day.[6]

De-orbiting and splash down[edit]

Dennis Pivnyuk who is the chief financial officer of the Russian Satellite Communications Co, informed on 15 March that the satellite would be decommissioned, and de-orbited. He stated that the descent phase would start on 20 March, with a splashdown in the Pacific Ocean around 26 March. The Ekspress AM4 satellite fell back to earth into the ocean on 28 March.[7]

References[edit]

  1. ^ McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 30 October 2013. 
  2. ^ McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page. Retrieved 30 October 2013. 
  3. ^ Second Life for Failed Russian Satellite. Retrieved 1 April 2012
  4. ^ Fiery Death of Wayward Russian Satellite Mourned by Company. Retrieved 1 April 2012
  5. ^ Repurposing Express-AM4: Mission Possible: Recycling Space Junk into Antarctic Science Treasure. Retrieved 1st April 2012
  6. ^ Lost Russian Communications Satellite Found in Wrong Orbit. Retrieved 1st April 2012
  7. ^ Dead Russian Satellite to Fall From Space. Retrieved 1st April 2012

External Links[edit]

  • IMS Official provider's site