The Space Shuttle program, officially called the Space Transportation System (STS), 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 land like a glider at either the Kennedy Space Center or Edwards Air Force Base.
The Shuttle is the only winged manned spacecraft to have achieved orbit and land, and the only reusable manned space vehicle that has ever made multiple flights into orbit (the Russian shuttle Buran was very similar and had the same capabilities but made only one unmanned spaceflight before it was cancelled). Its missions involved carrying large payloads to various orbits (including segments to be added to the International Space Station (ISS)), providing crew rotation for the space station, and performing service missions. The orbiter also recovered satellites and other payloads (e.g., from the ISS) from orbit and returned them to Earth, though its use in this capacity was rare. Each vehicle was designed with a projected lifespan of 100 launches, or 10 years' operational life, though original selling points on the shuttles were over 150 launches and over a 15-year operational span with a 'launch per month' expected at the peak of the program, but extensive delays in the development of the International Space Station [10] never created such a peak demand for frequent flights.
Although the concept had been explored since the late 1960s, the program formally commenced in 1972, and was the sole focus of NASA's manned operations after the final Apollo and Skylab flights in the mid-1970s. The Shuttle was originally conceived of and presented to the public in 1972 as a 'Space Truck' which would, among other things, be used to build a United States space station in low Earth orbit during the 1980s and then be replaced by a new vehicle by the early 1990s. The stalled plans for a U.S. space station evolved into the International Space Station and was formally initiated in 1983 by U.S. President Ronald Reagan, but the ISS suffered from long delays, design changes and cost over-runs [10] and forced the service life of the Space Shuttle to be extended several times until 2011 when it was finally retired — serving twice as long than it was originally designed to do. In 2004, according to the President George W. Bush's Vision for Space Exploration, use of the Space Shuttle was to be focused almost exclusively on completing assembly of the ISS, which was far behind schedule at that point
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