CAPE CANAVERAL, Fla. – A Pratt and Whitney Rocketdyne space shuttle main engine, or SSME, is rotated into a horizontal position with the aid of an engine-handling device attached to a crane inside the SSME Processing Facility, the engine shop at NASA’s Kennedy Space Center in Florida. The engine will be placed in a horizontal position on a portable workstand. The engine is one of the last SSMEs remaining at Kennedy and is being prepared for shipment to NASA's Stennis Space Center in Mississippi. The first two groups of engines were shipped from Kennedy to Stennis in November 2011 and January 2012 the remaining engines are scheduled to depart on April 9. Altogether, 15 shuttle-era engines will be stored at Stennis for reuse on NASA’s Space Launch System heavy-lift rocket, under development. Photo credit: NASA/Tim Jacobs KSC-2012-1916

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.