Proton Lofts SES-1 Satellite Into Orbit from Kazakhstan

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PARIS — An International Launch Services (ILS) Proton rocket on April 25 successfully placed the SES-1 telecommunications satellite into a near-geostationary orbit about nine hours after liftoff from the Russian-run Baikonur Cosmodrome in Kazakhstan. The satellite’s owner, SES of Luxembourg, said it had acquired signals that the satellite was healthy following separation from Proton’s Breeze-M upper stage.

SES-1, built by Orbital Sciences Corp. of Dulles, Va., will be moved into final geostationary orbit about 36,000 kilometers above the equator in the coming weeks and is expected to be ready for operations by SES by late May.

The satellite, formerly known as AMC-4R, will operate at SES World Skies’ 101 degrees west orbital slot covering North America and will replace the AMC-2 and AMC-4 spacecraft there now. SES-1 uses Orbital’s Star 2.4-E platform and carries 24 C- band and 24 Ku-band transponders.

SES, which has entered into multi-satellite launch contracts with Reston, Va.-based ILS and with the Arianespace consortium of Europe, contracted with Orbital for three nearly identical satellites, with an option for two more.

SES-1 weighed 2,550 kilograms at launch, making it a light load for the Proton-Breeze-M, which can lift satellites weighing more than 6,000 kilograms into geostationary transfer position.

The light weight of the satellite permitted the Proton to drop off SES-1 into a circular equatorial orbit less than 2,000 kilometers below the geostationary arc, which is the destination of most communications satellites. That permitted SES-1 to use less of its own on-board fuel to reach its final orbit than it would have had it been released in the typical geostationary transfer orbit, resulting in an estimated service life of 16 years rather than the standard 15 years.

SES-1 uses the same basic Star-2 platform design used by the Intelsat Galaxy 15 satellite that lost communications with ground teams in April. Orbital officials said the most probable cause is the intense solar storms that occurred in the first week of April.

SES Chief Executive Romain Bausch said SES continued with its launch without waiting for the Galaxy 15 anomaly-review board’s final conclusions because SES-1 includes backup systems that are not on board Galaxy 15.

The launch was the 22nd Proton flight in 21 months and the third mission for ILS — which sells Proton on the commercial market — this year. The company has said it hopes to conduct seven to eight commercial launches in 2010 after seven in 2009.