Cool article from Wired about the birth of GPS as we know it…
1993: The U.S. secretary of defense opens the global positioning system to civilian use. It’s about to change how people see where they are.
The GPS story starts with Sputnik, the first artificial satellite. The night after it was launched by the Soviet Union in 1957, researchers at MIT were able to track Sputnik’s orbit by its radio signal. And if you can track satellites from Earth, you can figure out how to locate objects on (or just above) Earth from the positions of satellites.
The U.S. Navy experimented with a satellite navigation system for its submarines in the mid-1960s. The Transit System used six satellites in circumpolar orbits, calculating the Doppler shift of radio signals to ascertain position.
Originally called the Navstar Global Positioning System, the outlines of the current GPS were conceived at the Pentagon in 1973. Testing began the following year, and the first operational GPS satellite was launched in 1978. It became clear in 1979 that the initially planned 18 satellites would not provide sufficient coverage, so the number was increased to 24 (including three substitutes).
The system was intended for military uses like targeting missiles, as well as peacekeeping uses like monitoring nuclear-bomb tests outlawed by the 1963 Nuclear Test Ban Treaty. But, after Korean Airline Flight 007 wandered into Soviet territory in 1983 and was shot down with a loss of 269 lives, even the military thought there might be distinct advantages to sharing the GPS system with civilians.
