Salyut

Salyut refers to a series of Soviet orbital space stations launched between 1971 and 1986 as part of the DOS program. The stations were designed to demonstrate long-duration human spaceflight, test life-support and docking systems, and pave the way for future space stations. The program produced nine orbital habitats designated Salyut 1 through Salyut 7, with a mix of civilian research missions and those linked to the overlapping Almaz military program.

Salyut 1, launched in 1971, became the first space station to host a crew and to sustain a long-duration stay in orbit. Salyut 2, launched in 1973, failed to achieve a stable orbit and did not host a crew. Salyut 3 and Salyut 4 in the mid-1970s conducted successful manned missions, while Salyut 5 supported shorter, focused crew activities. Salyut 6, launched in 1977, introduced a dual-docking capability and the ability for multiple crews to visit or reside on the station, greatly increasing utilization. Salyut 7, launched in 1982, continued long-duration operations and remained in use until the advent of the Mir program, and it is noted for sustained on-orbit activities and a later repair mission during its operational life.

The Salyut program contributed significantly to understanding long-term life-support, on-orbit maintenance, and crew rotation, providing essential experience that informed the design and operation of Mir. The series marked the first generation of true space stations and established design and operational precedents that influenced later multinational space-station concepts. The Salyut program concluded as Soviet space-station development shifted toward Mir, with the final station reentering in the early 1990s.