Orbital station (OS) “Mir”.

The orbital station (OS) "MIR" was put into orbit on Feb, 20, 1986. Today OS “MIR” is a multi-purpose scientific-research complex that incorporates a core module and five specialized equipment modules.

The overall mass of OS "MIR" with two spaceships attached is over 136 tons.

The overall volume of air-tight modules is about 400 cubic meters.

The length of OS "MIR" (core module, Kvant module and two docked spaceships) is 33 meters.

The first crew of "MIR" ( Leonid Kizim and Vladimir Solovyev) took off on March 13, 1986 to dock their Soyuz T-15 spacecraft with OS "MIR" on March 15. The crew performed the flight to “Salyut-7” to carry out scientific experiments onboard this station and complete its scientific program. Then the cosmonauts returned to OS “MIR” and bring about 300 kg of scientific equipment.

96 cosmonauts visited “MIR”, 19 of them did it twice, Alexander Viktorenko - four times, Anatoly Solovyev - five times. 70 space walks were performed and two space walks - to the Kvant unpressurized module totaling 330 hr 08 min. Moreover, two space walks (with the overall duration of 10 hr 56 min) were carried out from Atlantis spacecraft when the latter was docked to OS “MIR”. The Russian cosmonaut Vladimir Titov took part in the second space walk.

The international crews of primary expeditions began to work onboard OS “MIR” since 1995. The first international crew had an American astronaut and the second one - the astronaut from the European Space Agency. Starting from march, 1996 the interchanging US astronauts have been doing a continuous work onboard “MIR” along with the Russian cosmonauts.

15 visiting crews (duration from one week to one month) have worked with primary crews onboard OS “MIR”. 14 of those were international crews with cosmonauts from Syria, Bulgaria, Afghanistan, France (5 times), Japan, Great Britan, Austria, Germany (twice), European Space Agency. In addition, there were seven short-term (3-5 days) visiting missions flown by Atlantis and one mission by “Endeavor” to bring to OS “MIR” 34 US astronauts (six more were flown for long-term primary expeditions), one Canadian astronaut, one from European Space Agency, one from France and three Russian astronauts.

The folloing endurance records were established during the operation of “MIR”: 1987 - Yuri Romanenko (326 days), 1988 - Vladimir Titov and Musa Manarov (366 days), 1995 - Valery Polyakov (438 days). Valery Polyakov is also a holder of the world’s overall flight endurance record (679 days in two flights). The world’s endurance records among women were established in 1995 by Elena Kandakova (169 days) and in 1996 by US Shenon Lusid (188 days, 183 of which were spent onboard “MIR”).

27 space ships “Soyuz TM” and “Soyuz T” were launched to fly cosmonauts to OS “MIR”.

To support the crew operations onboard OS “MIR” 18 unmanned cargo ships “Progress” and 39 ships “Progress M” were launched. They delivered about 130 tons of payload: fuel for the integrated engine facility, equipment, scientific instruments, food and water, life support gear and etc.

The built-in maintainability of OS “MIR” has become one of its advantages. Preventive maintenance measures undertaken at regular intervals made it possible to increase the OS “MIR” lifetime several times.

The “MIR” 12-year flight, onboard operations carried out by many crews is an invaluable experience in near space exploration that allowed to develop long-term flight support techniques which are of vital importance for the development of the future international space station.