Sputnik
When the Russians launched Sputnik in 1957 it became apparent to scientists that satellites could be used for navigation. MIT managed to track Sputnik via its radio signal and surmised that if a satellite could be tracked from the ground then a satellite could also be used to track a person on the ground's whereabouts.
1970s
The Navstar GPS began development in 1973 with prototype satellites being launched in 1978.
1990s
By 1993 there were 24 satellites in place. In 1996 the president issued a directive making GPS a dual-use system for both civilian and military, with civilian signals being degraded.
2000s
May 2000 saw the degraded civilian signal discontinued, thus allowing users to get a non-degraded signal. In 2004 the U.S. Government agreed to work together with Europe's own planned Galileo satellite system. Also in 2004, Qualcomm successfully completed tests of GPS use in cellphones.
Today
Today there are over 30 GPS satellites orbiting Earth and GPS systems are in regular use. There is even a popular game amongst hikers called geocaching, which centers on GPS use.
Article Written By Shiromi Nassreen
Shiromi Nassreen has been writing professionally since 2005. She specializes in travel and outdoor topics, and her articles have appeared in various print and online publications, including "DISfunkshion Magazine" and Matador Travel. Nassreen holds a Bachelor of Arts in theatre studies from Rose Bruford College of Speech & Drama.
