Why don't satellites fall out of the sky?

Why don't satellites fall out of the sky?

Satellites travel around Earth without extra propulsion. They remain in orbit despite the Earth's gravitational pull because they travel so extremely rapidly. If there were a satellite that orbited very close to Earth's surface, it would have to travel at 7.9 km/sec., or 22 000 km/h. The need for speed reduces with increasing altitude. At a height of 400 km - at about the same altitude as the orbit of the International Space Station - the speed has fallen to 7.7 km/sec.