Mir Core Module

Mir (Russian: Мир, IPA: [ˈmʲir]; lit. Peace or World), DOS-7, was the first module of the Soviet/Russian Mir space station complex, in low Earth orbit from 1986 to 2001. Generally referred to as either the core module or base block, the module was launched on 20 February 1986 on a Proton-K rocket from LC-200/39 at the Baikonur Cosmodrome. The spacecraft was generally similar in design to the two previous Soviet orbital stations, Salyut 6 and Salyut 7, however possessed a revolutionary addition in the form of a multiple docking node at the forward end of the module. This, in addition to the docking port at the rear of the spacecraft, allowed five additional modules (Kvant-1 (1987), Kvant-2 (1989), Kristall (1990), Spektr (1995) and Priroda (1996)) to be docked directly to DOS-7, greatly expanding the station's capabilities.

Designed as a 'habitat' or 'living' module, DOS-7 possessed less scientific apparatus than its predecessors (lacking, for instance the large imaging camera which had partially obstructed the living areas of previous stations), instead providing crews with a comfortable living area on the station. Other changes made to DOS-7 from its predecessors included larger solar arrays and a new power system, greater automation and a new docking system, Kurs, in addition to the older Igla system. The spacecraft also featured a small trash/science airlock, and an aluminium hull (about 1 to 5 mm thick) with several portholes with hatches for viewing out. Inside, the spacecraft featured two-toned colours, fluorescent lighting, and one toilet. The module was launched unmanned, and first crewed by the two members of EO-1, launched aboard Soyuz T-15 on 13 March 1986. After 52 days, they left Mir and visited Salyut 7 for 51 days, then returned to Mir for 21 additional days, before returning to Earth on 16 July 1986. This is the only occasion in history when a crew transferred between two different space stations.

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