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CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, space shuttle Atlantis seems to tower above the mobile launcher platform after the pad’s rotating service structure, or RSS, has been rolled back. The RSS is retracted in preparation for Atlantis’ liftoff on the STS-125 mission to service NASA's Hubble Space Telescope. The rotating structure provides protected access to the shuttle for changeout and servicing of payloads at the pad. After the RSS is rolled back, the orbiter is ready for fuel cell activation and external tank cryogenic propellant loading oper…
