What is the International Space Station?
The International Space Station, or ISS, is a large laboratory orbiting Earth about 400 kilometers up. Astronauts have lived on it continuously since November 2000.
The ISS is a joint project of five space agencies: NASA, Russia's Roscosmos, the European Space Agency, Japan's JAXA and the Canadian Space Agency. Its first module launched in 1998, and it was assembled piece by piece over more than a decade. It is about the size of a football field, including its solar panels.
The station orbits Earth about every 90 minutes, so crew members see around 16 sunrises and sunsets each day. Astronauts conduct experiments in biology, medicine, physics and materials science, studying how microgravity affects the human body and how things behave without strong gravity.
The future of the ISS
The ISS is planned to operate until around 2030. NASA has chosen SpaceX to build a vehicle that will push the station out of orbit to burn up over a remote part of the Pacific Ocean. Private companies are developing commercial space stations to take its place.
Did You Know?
On a clear night, the ISS can be seen from the ground with the naked eye. It looks like a bright, fast-moving star with no flashing lights.