ISS Tracker

The International Space Station is the largest human-made structure in space, stretching 109 meters from end to end -- roughly the size of an American football field. Construction began on November 20, 1998, with the launch of the Russian Zarya module, and the station has been continuously occupied since November 2, 2000, making it the longest-running continuous human presence in space with over 25 years of uninterrupted habitation.

Orbiting at an altitude of approximately 408 kilometers (253 miles) above Earth's surface, the ISS travels at a speed of roughly 27,600 km/h (17,150 mph). At this velocity, it completes one orbit around Earth every 92 minutes, experiencing about 16 sunrises and sunsets each day. The station's orbit is inclined at 51.6 degrees relative to the equator, allowing it to pass over approximately 90 percent of Earth's populated surface.

The ISS serves as a microgravity research laboratory where crews of typically 6 to 7 astronauts conduct experiments in biology, physics, materials science, and Earth observation. Research conducted aboard the station has contributed to advances in medical treatments, water purification technology, and our understanding of how the human body adapts to long periods in space -- knowledge essential for future missions to the Moon and Mars.

Crew members are transported to and from the station aboard SpaceX Crew Dragon capsules and Russian Soyuz spacecraft. Standard crew rotations last approximately six months, though some astronauts have stayed for nearly a full year. The station is visible to the naked eye from Earth and appears as a bright, fast-moving point of light, often outshining the brightest stars. It is a collaborative project involving five participating space agencies: NASA, Roscosmos, ESA, JAXA, and CSA.