For many years satellite communications mostly utilized satellites in geostationary orbits, in which the satellite remains directly overhead at a fixed location on the Equator at an altitude of 35,786 km (22,236 mi). More recently, alternative satellite orbits have been seen to have distinct advantages and have found increasing use. Modern global communications networks have been developed using constellations of satellites in low Earth orbit. Specifically, the Iridium system makes it possible to make or receive calls from anywhere in the world using a handheld mobile telephone, while the SkyBridge system will provide worldwide broadband communications services. The advantages of satellite orbits that are geosynchronous but not geostationary are to provide services to geographical regions at high latitudes.