The first artificial satellites orbiting the Earth paved the way for numerous applications. On 11 July 1962, the first transatlantic video link was established thanks to the American Telstar 1 satellite. The operational geostationary orbit at an altitude of 36,000 km enabled a satellite to remain in a fixed position for an observer on the ground and went on to revolutionise methods of communication. There are now almost 250 satellites in space carrying live TV signals as well as Internet and telephone connections.