Space shuttle Discovery is revealed during sunrise after the rollback of the rotating service structure.

On Launch Pad 39A at NASA's Kennedy Space Center in Florida, space shuttle Discovery is revealed during sunrise after the rollback of the rotating service structure, or RSS. 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 Discovery's scheduled 1:36 a.m. EDT liftoff Aug. 25 with a crew of seven on the STS-128 mission. The service structure provides weather protection and access to the space shuttle at the launch pad. The 13-day mission will deliver a new crew member and 33,000 pounds of equipment to the International Space Station. The equipment includes science and storage racks, a freezer to store research samples, a new sleeping compartment and the COLBERT treadmill. STS-128 will be Discovery's 37th mission and the 30th shuttle flight dedicated to station assembly and maintenance. Photo credit: NASA/Troy Cryder