CAPE CANAVERAL, Fla. - Workers escort space shuttle Endeavour as it is towed to the Mate-Demate Device, or MDD, at NASA's Kennedy Space Center in Florida after being backed out of the Vehicle Assembly Building. The MDD is located at the Shuttle Landing Facility at Kennedy. The shuttle will be lifted and connected to the top of NASA's Shuttle Carrier Aircraft SCA, a modified 747 jetliner. The shuttle has been fitted with an aerodynamic tailcone for its flight aboard the SCA to Los Angeles where it will be placed on public display. Photo credit: NASA/Dmitri Gerondidakis KSC-2012-5117

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.