Space station

A space station (or orbital station) is a spacecraft which remains in orbit and hosts humans for extended periods of time. It therefore is an artificial satellite featuring habitation facilities. The purpose of maintaining a space station varies depending on the program. Most often space stations have been research stations, but they have also served military or commercial uses, such as hosting space tourists.

Space stations have been hosting the only continuous presence of humans in space. The first space station was Salyut 1 (1971), hosting the first crew, of the ill-fated Soyuz 11. Consecutively space stations have been operated since Skylab (1973) and occupied since 1987 with the Salyut successor Mir. Uninterrupted occupation has been sustained since the operational transition from the Mir to the International Space Station (ISS), with its first occupation in 2000.

Currently there are two fully operational space stations – the ISS and China's Tiangong Space Station (TSS), which have been occupied since October 2000 with Expedition 1 and since June 2022 with Shenzhou 14. The highest number of people at the same time on one space station has been 13, first achieved with the eleven day docking to the ISS of the 127th Space Shuttle mission in 2009. The record for most people on all space stations at the same time has been 17, first on May 30, 2023, with 11 people on the ISS and 6 on the TSS.^[1]

Space stations are most often modular, featuring docking ports, through which they are built and maintained, allowing the joining or movement of modules and the docking of other spacecrafts for the exchange of people, supplies and tools. While space stations generally do not leave their orbit, they do feature thrusters for station keeping.