Discovery looks polished and ready for launch on the STS-124 mission after rollback of the rotating service structure.

Bathed in lights surrounding Launch Pad 39A and its structures at NASA's Kennedy Space Center, space shuttle Discovery looks polished and ready for launch on the STS-124 mission after rollback of the rotating service structure. First motion was at 8:33 p.m. and rollback was complete at 9:07 p.m. The rotating structure provides protected access to the shuttle for changeout and servicing of payloads at the pad. It is supported by a rotating bridge that pivots on a vertical axis on the west side of the pad's flame trench. After the RSS is rolled back, the orbiter is ready for fuel cell activation and external tank cryogenic propellant loading operations. The pad is cleared to the perimeter gate for operations to fill the external tank with about 500,000 gallons of cryogenic propellants used by the shuttle’s main engines. This is done at the pad approximately eight hours before the scheduled launch. Along with the orange external tank and one of the two solid rocket boosters, the orbiter access arm is seen extended to the side of the shuttle. At the end is the White Room, which provides access into the shuttle. The STS-124 mission is the second of three flights launching components to complete the Japan Aerospace Exploration Agency's Kibo laboratory. The shuttle crew will install Kibo's large Japanese Pressurized Module and its remote manipulator system, or RMS. The 14-day flight includes three spacewalks. Launch is scheduled for 5:02 p.m. May 31. Photo credit: NASA/Troy Cryder