Satellite TV uses a wireless system of transmitting radio signals to deliver its
Television programming to the viewer’s home or business. A radio signal can only travel in a straight line however. Enter the satellite. By placing an orbiting satellite at 37,000 km (22,300 miles) above the earth and having it match the earth’s rotational speed (7,000 miles per hour) the satellite stays over the same spot above the earth. This is referred to as being in geosynchronous orbit.
These orbits are sometimes also referred to as Clarke orbits in honor of Arthur C. Clarke who first came up with the idea in an article he wrote back in 1945 entitled “Extraterrestrial Relays” published in Wireless World Magazine.  Read more...