KENNEDY SPACE CENTER, Fla. -- In the early morning hours, the Rotating Service Structure (left) begins rolling back to free Space Shuttle Discovery for launch of mission STS-92 at 8:05 p.m. Oct. 9. Above the external tank can be seen the Gaseous Oxygen Vent Arm with its vent hood, commonly referred to as the “beanie cap.” The system is designed to vent gaseous oxygen vapors away from the Shuttle after cryogenic loading. The scheduled launch is the second attempt after an earlier scrub. STS-92 is making the fifth flight for construction of the International Space Station. The mission is also the 100th in the history of the Shuttle program KSC-00pp1508

The Space Shuttle program was the United States government's manned launch vehicle program from 1981 to 2011, administered by NASA and officially beginning in 1972. The Space Shuttle system—composed of an orbiter launched with two reusable solid rocket boosters and a disposable external fuel tank— carried up to eight astronauts and up to 50,000 lb (23,000 kg) of payload into low Earth orbit (LEO). When its mission was complete, the orbiter would re-enter the Earth's atmosphere and lands as a glider. Although the concept had been explored since the late 1960s, the program formally commenced in 1972 and was the focus of NASA's manned operations after the final Apollo and Skylab flights in the mid-1970s. It started with the launch of the first shuttle Columbia on April 12, 1981, on STS-1. and finished with its last mission, STS-135 flown by Atlantis, in July 2011.