CAPE CANAVERAL, Fla. – Space shuttle Discovery rolls from Orbiter Processing Facility 3 to the Vehicle Assembly Building (in the background) at NASA's Kennedy Space Center, Fla. The first motion of the shuttle out of its hangar was at 7:22 a.m. EDT. In the VAB, Discovery will be lifted into High Bay 1 and mated to the external fuel tank and solid rocket boosters already installed on the mobile launcher platform. The shuttle is scheduled to roll out to Launch Pad 39A the first week of August to prepare for the STS-128 mission to the International Space Station. Discovery will carry the Leonardo Multi-Purpose Logistics Module containing life support racks and science racks and the Lightweight Multi-Purpose Experiment Support Structure Carrier in its payload bay. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett KSC-2009-4239

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.