Salyut 7

Salyut 7, also known as DOS-6, was a Soviet space station in low Earth orbit from April 1982 to February 1991. It was launched on 19 April 1982 on a Proton-K rocket from Baikonur and first crewed in May 1982 by two cosmonauts arriving in Soyuz T-5. It was the backup vehicle for Salyut 6 and very similar in equipment, launched when delays to the Mir programme left a gap. The station was visited by ten crews in six main expeditions and four secondary flights, including French and Indian cosmonauts, and Svetlana Savitskaya made a spacewalk from it. Heavy Kosmos modules, variants of the TKS spacecraft, were docked to it to test the use of large modules, which helped engineers develop the technology needed for Mir. Salyut 7 was the last of the monolithic Salyut stations before the modular Mir.