Thinking About Satellites...

Have you ever wondered how people back in the United States had instant access to an incredible amount of intelligence information about the strategic situation during the Gulf War?

Or how it is that you can just pick up the telephone and routinely communicate with someone anywhere in the world... including on board a commercial airplane?

We rely every day on satellites orbiting the Earth.

Click on the satellite image to see some of the many everyday uses of earth-orbiting satellites.

In the last lesson, we began to study the satellites which make up the GPS ("Global Positioning System") network.

Someone figured out where to put them. That is, someone computed exactly what kind of orbit each one needs. How is this done? What's behind this? Let's find out.

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