The Mir orbital complex is the world’s first orbital station built on a modular basis, when other elements that are necessary to perform certain functions can be attached to the base unit. It was operated in low-earth orbit from February 20, 1986 (since the launch of the base unit) to March 23, 2001.
At the initial stage of operation of the Mir orbital station, its operation was possible only in the visiting mode, and operation in the mode of a permanent station was limited due to the lack of the necessary means of the motion control system and the life support system. The first manned flight on the Soyuz T-15 spacecraft was carried out from March 15 to July 16, 1986.
The crew consisting of cosmonauts Leonid Kizim and Vladimir Solovyov during this time carried out work on de-mothballing the base unit and preparing it for an unmanned flight, accepted and unloaded two cargo ships of the Progress series, and then for the first time made a flight from the Mir station to Salyut-7 and back. While on board the Salyut, the cosmonauts performed two spacewalks with a total duration of 8 hours and 50 minutes to deploy and test a sliding truss.
The cosmonauts returned to the Mir on June 25-26. They transferred 20 devices with a total mass of 350-400 kg from Salyut-7 to Mir. On July 3, Leonid Kizim broke Valery Ryumin’s record for being in space, and on July 6, he became the first person to stay in space for a year in cumulative time.
The operation of the Mir orbital complex in the mode of a permanent station was started on February 8, 1987 and continued until August 1999 with one break from April 27 to September 8, 1989. The change of expeditions was carried out directly on board the complex. Since 1987, the station has been implementing international research programs. Astronauts from France, Syria, Afghanistan, Bulgaria, Japan, Great Britain, Germany, Kazakhstan, Austria, USA, Canada and countries of the European Space Agency took part in their implementation directly on board the station. During 1995-1998, joint Russian-American work was carried out at the station under the Mir-Shuttle and Mir-NASA programs.