Series of Soviet orbiting space laboratories, visited and operated in orbit by a number of SOYUZ crews. The first Salyut was launched on 19 April 1971 into a close Earth orbit (PERIGEE altitude 200 km) and the first docking with a Soyuz craft took place five days later (but with no transfer of crew to the Salyut). On 7 June 1971, the Soyuz 11 crew (Dobrovolsky, Volkov and Patsayev) docked and spent twenty-three days in the space station. Tragically, due to a pressure leak in the Soyuz craft, the crew died during the re-entry of the Earth's atmosphere. Subsequent Salyut stations have been visited for extended periods by two-man Soyuz crews.
The Salyut, when docked with a Soyuz craft (which makes up an integral part of the working laboratory), has an overall length of 23 metres, a mass of 25 tonnes, and provides a habitable volume of about 100 cubic metres. Scientific studies carried out on board include Earth observations, biological studies and astronomical observations.
