NASA

The National Aeronautics and Space Administration, the government agency behind the nation's space program, was established in 1958 and is headquartered in Washington, D.C. As of 2015 it had 17,300 civil servant employees across the country. The vast majority of American space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle, the Space Launch System and commercial crew vehicles. Read Less