For some time now, there have been a number of satellites orbiting the earth at a distance of 12,000 miles. They are constantly on the move and orbit our planet every 24 hours. Why do we care? What do they have to do with our every day life? They are known as the GPS satellite network and they are becoming more and more a part of our daily lives. Originally created by the Unites States Department of Defense, this satellite network is still, to this day, overseen by the United States Air Force 50th Space Wing. In March of this year, 2008, the number of satellites were increased from 24 to 38. They have solar panels that are attached to their bodies which power them to travel at 7,000 mph and to help them to stay on course; they use small booster rockets which keep them on the correct orbit and they each orbit the earth in less than 24 hours.

If you are in the market for a GPS, there are three common types available and they are termed navigation, tracking and location. Navigation enables you to literally navigate anywhere, whether you are in the car or on the sea. We have President Ronald Reagan to thank for the GPS because he was responsible in 1983 for allowing the public to access this incredibly valuable satellite network.

It is based upon a simple premise. The GPS sends out a signal and this is intercepted by up to four or more satellites, which then return the signal, pinpointing your exact location. One of the most appreciated uses of the GPS is on the seas. Again, there are choices available, one of the most popular being specific to the waters traveled. Chartplotters and Bluechart g2 have maps of the ocean beds, mostly US based, but which include Alaska and Hawaii.

The GPS is particularly useful for the fisherman because of its ability to map the ocean floors which can change with each storm. The GPS unit will show the difference in depth which is helpful for keeping track of the movements of fish. The best fishermen are watching for the feeding grounds of the shoals of fish, which the waterproof GPS unit will enable you to do. By knowing the various depths of the ocean or lake, the fisherman is able to predict the movement of the fish, remembering that when the weather is cool the fish like to go deep. In the warmer weather, they stay closer to the surface.

One interesting and little known fact relates to the well known science fiction writer, Arthur C. Clarke, author of such famous titles as 'Childhood's End' and The City and the Stars'. He is probably best known for his work with Stanley Kubrick on "2001, A Space Odyssey". He was born in Somerset, England, now lives in Sri Lanka and is generally considered to be the man who first came up with the idea of the communications satellite, which we now know as the GPS.