![ISS Facts](https://webarchive.library.unt.edu/eot2008/20080921200018im_/http://solarsystem.nasa.gov/missions/images/miss-iss-facts.jpg)
Astronaut Sunita Williams (right) ran the complete Boston Marathon on a treadmill aboard the space station in 2007.
NASA, the European Space Agency, Russia, Japan, Canada and Brazil are collaborating to build the station.
When complete, the space station will have the equivalent mass of about 330 cars -- 419,600 kg (925,000 lbs).