National Aeronautics and Space Administration

The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program name was Space Transportation System (STS). Five complete Space Shuttle orbiter vehicles were built and flown on a total of 135 missions from 1981 to 2011.