The final countdown testing in preparation for the March 15 launch of space shuttle Atlantis began Wednesday at the Kennedy Space Center in Florida.
The National Aeronautics and Space Administration said the flight crew of mission STS-117 will participate in the full launch dress rehearsal that continues through Friday. Such tests typically take place a few weeks prior to a launch and provide the crew an opportunity to participate in various simulated countdown activities, including equipment familiarization and emergency egress training.
Atlantis arrived at Launch Pad 39A last week from the Vehicle Assembly Building where it was mated with its external fuel tank and solid rocket boosters. The orbiter's launch will be the first from Pad 39A in four years.
During countdown tests, the shuttle will undergo final testing, payload installation and a "hot fire" test of auxiliary power units. When testing is completed, the rotating service structure will be moved around the vehicle for protection.
During the 11-day mission to the international space station, the six-member crew will install a new truss segment, retract a set of solar arrays and unfold a new set.
Copyright 2007 by United Press International
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