Rollback on Launch Pad 39A, Space Shuttle Atlantis stands bathed in lights atop a mobile launch platform.

Following rollback of the rotating service structure, or RSS, on Launch Pad 39A, Space Shuttle Atlantis stands bathed in lights atop a mobile launch platform. Rollback is one of the milestones in preparation for the launch of mission STS-117 on June 8. Rollback started at 10:56 p.m. and was complete at 11:34 p.m EDT. The RSS provides protected access to the orbiter for changeout and servicing of payloads at the pad. Connecting the RSS to the cockpit of the shuttle is the orbiter access arm with the White Room extended. The White Room provides access into the orbiter for the astronauts. This mission is the 118th shuttle flight and the 21st U.S. flight to the International Space Station and will deliver and install the S3/S4 truss segment, deploy a set of solar arrays and prepare them for operation. Photo credit: NASA/Kim Shiflett