Space shuttle Endeavour is revealed after the rollback of the rotating service structure or RSS.

On Launch Pad 39A at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is revealed after the rollback of the rotating service structure, or RSS. In the foreground is the flame trench, which the mobile launcher platform straddles. On top of the external fuel tank is the oxygen vent hood, called the "beanie cap," which is designed to vent gaseous oxygen vapors away from the shuttle. The rollback is preparation for Endeavour's liftoff June 13 on the STS-127 mission with a crew of seven. First motion was at 10:39 a.m. EDT and completed at 11:18 a.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 launch will be Endeavour's 23rd flight. The shuttle will carry the Japanese Experiment Module's Exposed Facility, or JEM-EF, and the Experiment Logistics Module-Exposed Section, or ELM-ES, on STS-127. The mission is the final of three flights dedicated to the assembly of the Japan Aerospace Exploration Agency's Kibo laboratory complex on the space station. Endeavour's launch is scheduled for June 13 at 7:17 a.m. EDT. Photo credit: NASA/Jim Grossmann