The International Space Station (ISS) orbits Earth in a low-Earth orbit (LEO) at an altitude of approximately 250 miles (402 kilometers). The ISS orbits Earth every 90 minutes, traveling at a speed of about 17,500 miles per hour. Features of the ISS orbit The ISS's orbital inclination is 51.6°, which allows it to fly over more than 90% of the inhabited Earth. The ISS's orbit gradually decays due to atmospheric drag and the Earth's gravitational pull. The ISS's orbit is periodically adjusted usin