CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, space shuttle Atlantis rolls toward the open doors of Orbiter Processing Facility 1. Atlantis was demated from the Shuttle Carrier Aircraft, or SCA, via the mate/demate device at the Shuttle Landing Facility. After its May 24 landing at Edwards Air Force Base in California, which concluded its STS-125 mission, the modified Boeing 747 SCA carried the shuttle on a two-day ferry flight from Edwards to Kennedy beginning June 1. Atlantis' next assignment is the STS-129 mission, targeted to launch in November 2009. Photo credit: NASA/Jack Pfaller KSC-2009-3518

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.