Space: International Space Station (ISS)

International space station, or a habitable artificial satellite, in low Earth orbit. It is a modular structure whose first component was launched in 1998. Now the largest artificial body in orbit, it can often be seen at the appropriate time with the naked eye from Earth.

The project involves five space agencies: the United States' NASA, Russia's Roscosmos, Japan's JAXA, Europe's ESA, and Canada's CSA.

The ISS consists of pressurised modules, external trusses, solar arrays, and other components. ISS components have been launched by American Space Shuttles as well as Russian Proton and Soyuz rockets. In 1984, the ESA was invited to participate in Space Station Freedom. After the USSR dissolved, the United States and Russia merged Mir-2 and Freedom together in 1993.

The ISS serves as a microgravity and space environment research laboratory in which crew members conduct experiments in biology, human biology, physics, astronomy, meteorology, and other fields. The station is suited for the testing of spacecraft systems and equipment required for missions to the Moon and Mars.

Since the arrival of Expedition 1 on 2 November 2000, the station has been continuously occupied for over 22 years (as of March 2023), the longest continuous human presence in space. (In 2010, the station surpassed the previous record of almost 10 years (or 3,634 days) held by Mir.)

The station is serviced by a variety of visiting spacecraft: Soyuz, Progress, the Automated Transfer Vehicle, the H-II Transfer Vehicle, Dragon, and Cygnus. It has been visited by astronauts and cosmonauts from 15 different nations.