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Brief History of GPS
For centuries, people have been developing techniques to figure out
their position on Earth. Global Positioning System has evolved from the United States Navy to the twenty four satellite
constellation that it is now. The Navy ran two programs before GPS. The first was a satellite based navigation
system called Transit that was developed by Richard Kirschener in 1964. Transit consisted of seven satellites and
used radio signals. The second satellite navigation system which was built in 1967 was called Timation. This system
improved upon the Transit system by using an atomic clock. In 1973, the Navy and Air Force teamed up and formed the
Navigation Technology Program, which became Navigation System and Ranging or NAVSTAR, The first four satellites were
launched in 1978. It currently contains twenty four satellites that circle the Earth every twelve hours. These
satellites are travelling at speeds of roughly 7,000 miles an hour. GPS satellites are powered by solar energy. They
have backup batteries onboard to keep them running in the event of a solar eclipse, when there's no solar power. Small rocket
boosters on each satellite keep them flying in the correct path. GPS uses these "man-made stars"
as reference points to calculate positions accurate to a matter of meters. In fact, with advanced forms of GPS you can make measurements to better than a centimeter.GPS was
first used strictly for military, it has since moved to the private sector. For national security reasons, the public's
system is not as accurate as the military system. The military system allows an accuracy of 10m while the public's system
is only accurate up to 100m. These days GPS is finding its way into cars, phones, boats, planes,
construction equipment, movie making gear, farm machinery, even laptop computers. Within four to ten years,
the more precise system will be released to the public.
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