One of the world's topcommercial satellite operators used a heavy-lift Ariane 5 rocket tosuccessfully get two of its new communications spacecraft into orbit Saturdayevening.
It was a risky propositionfor Eutelsat to entrust a pair of its satellites to just one rocket. Neverbefore had the company put two pricey birds on a single launch. But when launchslots are increasingly difficult to secure, the Paris-based took theopportunity from launch provider Arianespace.
Blastingoff from the Guiana Space Center on the northeastern coast of SouthAmerica, the mammoth rocket carried out its crucial mission in only 32 minutes,as Eutelsat executives held their collective breaths.
The hydrogen-fueled Vulcain2 main engine ignited as the countdown hit zero at 2235:07 GMT (5:35:07 p.m.EST), followed seven seconds later by lighting the twin solid rocket boostersto propel the Ariane 5 from the jungle launch base.
The launch occurred on theday's second try. An initial countdown was halted a scant 10 seconds beforeignition because pressure in the liquid hydrogen system was out of spec. Thelaunch team recycled the clocks and resolved the issue for liftoff 44 minutesinto the hour-long window.
The solid motors providednearly 90 percent of the power during the early climb into the night beforeburning out and separating. That left the main stage to continue pushing thevehicle out of the atmosphere.
About 9 minutes afterliftoff, the cryogenic upper stage took control and performed a 16-minute burnthat accelerated the payload into the targeted geosynchronous transfer orbit at20,800 mph.
The two satellites, stackedatop each other, then began the choreographed deployment sequence that saw HotBird 9 released from the rocket 27 minutes into flight. The barrel-likestructure that held the top satellite and enclosed the lower spacecraft was jettisoneda few minutes later, exposing W2M for its separation from the upper stage tocomplete the launch.
"I think you alladmired this absolutely beautiful liftoff of Ariane," said GiulianoBerretta, Eutelsat's director general. "I would like to thank Arianespacefor this beautiful performance."
The workhorse Ariane 5 nowhas accumulated 28 consecutive successes over the past five-and-a-half years.
Both satellites will usetheir onboard engines to ascend from the launch orbit to circular geostationaryorbits 22,300 miles above the equator. Hot Bird 9 will be positioned at 13degrees East longitude and W2M is headed for 16 degrees East.
Eutelsat operates a clusterof three satellites at its 13 degrees East orbital slot to beam nearly 1,100television channels and 600 radio stations to 120 million homes across Europe,North Africa and the Middle East. Hot Bird 9 promises to increase the number ofdigital and high-definition TV offerings.
Built by EADS Astrium usingthe Eurostar E3000 platform, the craft is equipped with 64 Ku-band transpondersfor relaying transmissions directly to small dishes at users' homes.
A successful entry intoservice by Hot Bird 9 will allow the Hot Bird 7A spacecraft currently operatingat that location to be moved into the 9-degree East position for replacement ofthe 12-year-old Eurobird 9 craft.
Userswith dual-feed satellite dishes can receive programming from both the 9- and13-degree orbital positions.
The craft will replace theW2 satellite launched 10 years ago and enhance Eutelsat's capacity to coverburgeoning markets in central and eastern Europe, the Mediterranean Basin, theMiddle East and islands in the Indian Ocean region.
Eutelsat's two newsatellites will be joined by three more next year and two in 2010 as part ofthe company's fleet expansion and renewal efforts.
"This successful duallaunch of two Eutelsat satellites is a major step forward in our far-reachingin-orbit investment program for 2008-2011 and clears the way for Eutelsat toaccomplish a raft of strategic objectives in terms of managing our in-orbitresources," Berretta said.
"These new resourcesunderscore our ability to pursue sustainable growth in digital TV and broadbandmarkets, which continue to confirm their dynamic potential."
Saturday marked the sixthand final launch of 2008 for the Ariane 5. The hoped-for record pace of sevenmissions this year fell short due to payload schedules.
Arianespace began the yearwith the launch of Europe's first Automated Transfer Vehicle,the robotic resupply ship that spent five months docked to the internationalspace station. Five additional Ariane 5s flew during the year, each deliveringpairs of communications satellites into orbit.
Next up will be ArianespaceFlight 187, currently targeted for launch on February 12. It will carry HotBird 10 for Eutelsat and the delayed NSS 9 spacecraft for SES New Skies, thesatellite originallyslated for Saturday's mission but was replaced by W2M.
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