What is low earth orbit?

A low Earth orbit (LEO) is an orbit around Earth with an altitude of 2,000 km (1,200 mi) or less, and with an orbital period of between about 84 and 127 minutes. Objects below approximately 160 km (99 mi) will experience very rapid orbital decay and altitude loss due to atmospheric drag. read more

And for a time, all of our missions were what is known as Low-Earth Orbit (LEO). Over time, with the Apollo missions and deep space missions involving robotic spacecraft (like the Voyager missions), we began to venture beyond, reaching the Moon and other planets of the Solar System. read more

Low Earth orbit is not very high. Yes, we think about LEO as being way up there in space—and it is indeed very high. The International Space Station orbits 400 km above the Earth’s surface. read more