Primer On How GPS Works

Scientific American provides a fascinating introduction to how GPS devices work.

1 minute read

June 5, 2002, 11:00 AM PDT

By Chris Steins @planetizen


"The Global Positioning System (GPS) consists of 24 operating satellites and several spares. Some of these spare satellites are also in use or can readily be activated once an operating satellite becomes dysfunctional. Taking the specific orbits of this many satellites into consideration, an observer can see at least four satellites at any time from any location on the earth."

Thanks to Chris Steins

Monday, June 3, 2002 in Scientific American

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