It was part of the Soviet Salyut Programme, as a transition from monolithic to modular space stations. It was the last of the second generation of DOS-series space stations to be replaced by MIR, the modular 3rd generation. (Source: Wikipedia)

Model designed by Vad Kuz

Soyuz T updated on 6/14/23 (windows added, antennas adjusted, propulsion system more accurate)