Learn about latitude and longitude, the lines we use to measure position on the globe.
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Find out how GPS satellites provide your real-time position on Earth.
GPS data is combined with other technologies to locate 911 callers. A recent report suggests it is not accurate enough for most emergencies and greater accuracy should be a priority.
Do you know someone who has had trouble getting help in an emergency because of difficulty determining their location?
Everyone has a story — what's yours? Have you sailed the open seas? Has GPS ever let you down?
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