US manned orbiting space station constructed from components adapted from the APOLLO PROJECT, and which was placed into a 435 km altitude orbit on 14 May 1973. Crews were ferried to and from the laboratory by means of Apollo-type spacecraft. With the Apollo craft (the command service module) attached, Skylab had an overall length of 36 metres, and a mass of 90.6 tonnes, and the major component, the orbital workshop, provided a total of 292 cubic metres of laboratory and crew accommodation.
In all, three crews, each of three astronauts, spent a total of 513 man-days in space, carrying out a wide variety of experiments and observations. The areas which received most of the time allocation were solar astronomy (31 per cent of total), Earth observations (19 per cent), astrophysics (9 per cent) and life sciences (27 per cent); other areas of interest where work was undertaken included engineering technology and materials science. The final Skylab mission devoted much time to the study of comet Kohoutek.
Skylab proved to be an outstanding success, all the more so as the first crew had to carry out quite extensive repairs to damage incurred during its launching.
