International Space Station Russian space station called OPSEK. The ISS is the ninth space station to be inhabited by crews, following the Soviet and later Russian "Salyut", "Almaz", and "Mir" stations as well as "Skylab" from the US. The station has been continuously occupied for since the arrival of Expedition 1 on 2 November 2000. This is the longest continuous human presence in low Earth orbit, having surpassed the previous record of held by "Mir". It has been visited by astronauts, cosmonauts and space tourists from 17 different nations. After the American Space Shuttle programme ended in 2011, Soyuz rockets became the only
Space logistics significant focus of space logistics is on "upmass", or payload mass carried up to orbit from Earth, space station operations also have significant downmass requirements. Returning cargo from low-Earth orbit to Earth is known as transporting "downmass", the total logistics payload mass that is returned from space to the surface of the Earth for subsequent use or analysis. Downmass logistics are important aspects of research and manufacturing work that occurs in orbital space facilities. For the International Space Station, there have been periods of time when downmass capability was severely restricted. For example, for approximately ten months from the time