Salyut program

The Salyut programme (Russian: Салю́т, IPA: [sɐˈlʲut], meaning "salute" or "fireworks") was the first space-station programme undertaken by the Soviet Union. It involved a series of four crewed scientific-research space-stations and two crewed military-reconnaissance space-stations over a period of 15 years from 1971 to 1986. Two other Salyut launches failed. In one respect, Salyut had the task of carrying out long-term research into the problems of living in space and a variety of astronomical, biological and Earth-resources experiments, and on the other hand the USSR used this civilian program as a cover for the highly secretive military Almaz stations, which flew under the Salyut designation. Salyut 1, the first station in the program, became the world's first crewed space station.

Salyut flights broke several spaceflight records, including several mission-duration records, and achieved the first ever orbital handover of a space station from one crew to another, and various spacewalk records. The ensuing Soyuz program was vital for evolving space-station technology from a basic, engineering-development stage, from single docking=port stations to complex, multi-ported, long-term orbital outposts with impressive scientific capabilities, whose technological legacy continues to the present day^[update]. Experience gained from the Salyut stations paved the way for multimodular space stations such as Mir and the International Space Station (ISS), with each of those stations possessing a Salyut-derived core module at its heart.

Mir-2 (DOS-8), the final spacecraft from the Salyut series, became one of the first modules of the ISS. The first module of the ISS, the Russian-made Zarya, relied heavily on technologies developed in the Salyut programme.

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