| What is GPS? | How Does it Work? | Is It Accurate? | What Are GPS Signals? | What Are the Sources of Signal Error? | What Are the Uses of GPS? | What is the Future of GPS? | Bibliography |
The Global Positioning System, also known as the GPS, is made up of a network of around twenty-four satellites sent into orbit by the Department of Defense of the US. It is a navigation system which was initially meant to be used for US military purposes. However, in the 1980’s, civilians were allowed access to the system, too, by the US government. The Global Positioning System is able to function in any type of weather, in any location world-wide, at any time during the day. The use of GPS requires no subscription fees or set-up charges; it is free to all civilians.
The GPS is made up of 24 satellites that orbit the earth. These satellites are located about 12,000 miles above the earth’s surface. They are in constant motion and are able to complete two orbits in a day. GPS satellites travel at a speed of around 7,000 miles/hour. These satellites use solar energy for power, though they also contain backup batteries to keep them in motion when there is no solar energy, such as in a solar eclipse. Satellites are equipped with small rocket boosters which are used to prevent them from deviating from the correct path or obit.