Diagram of Skylab space station, 1973.
© National Aeronautics & Space Administration / Science & Society
This cut-away diagram of Skylab also shows two Saturn rockets and Apollo spacecraft, which carried crews to Skylab and a diagram of Skylab's Earth orbit. Skylab was launched on 14th May 1973 and was America's first manned orbiting space station. Visiting crews of three astronauts could perform dozens of tests on each other to find out how well the human body copes with space travel. Three crews visited Skylab during its working life, with the astronauts on the last mision launched in February 1974 staying in orbit for 84 days. Skylab was originally expected to stay in orbit for 8 to 10 years, but by 1977 the station's orbit was found to have become unstable, and Skylab crashed back to Earth on 11th July 1979.