Discovery is revealed on Launch Pad 39A NASA's Kennedy Space Center after the rotating service structure is rolling back.

Space shuttle Discovery is revealed on Launch Pad 39A NASA's Kennedy Space Center after the rotating service structure, or RSS, at left of the pad is rolling back. Rollback started at 3:34 p.m. EDT and was complete at 4:20 p.m. Beneath the shuttle is the mobile launcher platform which supports the shuttle until liftoff. The RSS provides protected access to the orbiter for changeout and servicing of payloads at the pad. Rollback of the pad's RSS is one of the milestones in preparation for the launch of mission STS-120. Discovery is scheduled for liftoff at 11:38 a.m. EDT on Oct. 23. The mission will be the 23rd assembly flight to the International Space Station and the 34th flight for Discovery. Payload on the mission is the Italian-built U.S. Node 2, called Harmony. The 14-day mission will install Harmony and move the P6 solar arrays to their permanent position and deploy them. Discovery is expected to complete its mission and return home at 4:47 a.m. EST on Nov. 6. Photo credit: NASA/Kim Shiflett