One never ceases to ponder at the marvels of science and how easy they have made our day to day lives. One just cannot imagine how these portable GPS units have changed the lives of many people for the better. It is amazing to see the various ways in which these marvels of science that rely on a cluster of 21 satellites have changed our lives. The golf player can now know the exact location he is away from the hole and therefore can adjust his shot accordingly. The cross country driver now is able to determine at what speed they are driving and their exact location along with the best route available for them to beat their fellow competitors.
Until a few years ago, these tasks would have been considered impossible, but today even sailors navigating the high seas to travel from one country to another rely on these portable GPS units. The portable GPS (global positioning system) unit or receiver can identify your exact location through the help of 21 active orbiting satellites that are stationed at a geo stationary location, 12,000 miles above the surface of the earth. This satellite system has been designed in such a way that they can track your movement and send details about your location to your GPS unit irrespective of your location on earth.
You might be high in the mountains or deep in the jungles or even crossing a great desert, yet these units will report back your exact location with unfailing accuracy. At any given point of time, 3 of these 21 satellites send signals to your GPS unit and the signal sent back to the satellite by this unit helps the software on the satellite to pinpoint your location by using a grid that tracks your location in latitude and longitude.
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