Skylab Skylab Skylab was a United States space station launched and operated by NASA, and occupied for about 24 weeks between May 1973 and February 1974 – the only space station the U.S. has operated exclusively. In 1979 it fell back to Earth amid huge worldwide media attention. Skylab included a workshop, a solar observatory, and other systems necessary for crew survival and scientific experiments. It was launched unmanned by a modified Saturn V rocket, with a weight of . Lifting Skylab into low earth orbit was the final mission and launch of a Saturn V rocket (famous for carrying the
Halo orbit each Lagrange point. Because halo orbits tend to be unstable, stationkeeping is required to keep a satellite on the orbit. Most satellites in halo orbit serve scientific purposes, for example as space telescopes. Robert W. Farquhar first used the name "halo" for these orbits in his 1968 Ph.D. thesis. Farquhar advocated using spacecraft in a halo orbit on the far side of the Moon (Earth–Moon ) as a communications relay station for an Apollo mission to the far side of the Moon. A spacecraft in such a halo orbit would be in continuous view of both the Earth and the