CAPE CANAVERAL, Fla. – In the White Room on Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-119 Mission Specialists Koichi Wakata (center) and Steve Swanson are getting into their harnesses, which include a parachute pack, before crawling through the open hatch into space shuttle Discovery. The White Room is at the end of the orbiter access arm on the fixed service structure and provides access into the shuttle. The STS-119 mission is the 28th to the International Space Station and the 125th space shuttle flight. Discovery will deliver the final pair of power-generating solar array wings and the S6 truss segment. Installation of S6 will signal the station's readiness to house a six-member crew for conducting increased science. Liftoff is scheduled for 7:43 p.m. EDT. Photo credit: NASA/Tony Gray, Tom Farrar KSC-2009-2056

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.