International Space Station (ISS)
EARTH ORBIT · permanently crewed
The biggest structure humans have ever put into space, about the size of a football field. It races around Earth in just 90 minutes, so the crew sees 16 sunrises and sunsets every day. People have lived and done research on board without a single break since the year 2000. On a clear evening you can spot it yourself: a bright dot gliding silently across the sky.