Global Positioning System - History of Global Positioning System

A Global Positioning System, otherwise known as a GPS, is commonly found throughout computers, cars, and cellphones today. Many people would be lost without their helpful directions and guidance. Until recently, the GPS units were only for military and research use, but their history is broad and begins with the first exploration of space.

In 1957, when Sputnik 1 was launched into orbit by the Soviet Union, it was believed that the precise location of the satellite would be indeterminable. However, William Guier and George Weiffenbach of the United States decided to research Sputnik's radio transmissions. To their great surprise, they realized that positional tracking of Sputnik's location was possible by using the Doppler effect of radio waves.

Immediately the U.S. Navy became interested in this ability, and employed Guier and Weiffenbach to create the first satellite navigational system, TRANSIT. Providing locational information once an hour, this was the first system that could detect a satellite's orbital location.

An Earth based navigational system, called OMEGA, was then developed in the 1970s. Fueled by nuclear threat of the Cold War, the U.S. military wanted to better specify potential locations for nuclear weapon development. Therefore, the first GPS was created for this purpose, and was kept as a highly guarded secret for almost a full decade.

Although there was a high demand for civilian GPS units, the technology was only available for military use until 1983. In this year President Ronald Reagan directed the technology to be freely available world wide after a passenger plane was accidently shot down over Soviet airspace.

Therefore, on February 14^th, 1989 the first satellite component of the current GPS network was launched into orbit. Completed in 1995, this network contains 24 satellites that orbit the Earth every 12 hours. One year later, the first civilian GPS units went up for sale. Today, the GPS development, accuracy, and price continue to improve, advancing locational technology for military and civilian use.