Orbit Explorations

Not all orbits are circular. In fact, some of the most useful surveillance satellites (spy satellites!) are in highly elliptical orbits.

One particular orbit, called a Molniya orbit, is used for surveillance purposes in regions of high latitudes. Rather than orbiting the Earth directly over the equator, for example, these satellites are in highly polar orbits.

Using the simulation, explore the Molniya spy satellite orbit. Adjust various parameters and notice how they affect the shape and period of the resulting orbit.

#1 Can you think of reasons why such satellites in elliptical orbits might be necessary and useful?

#2 At what location in its elliptical orbit does the satellite move fastest? At what location does it move the slowest? Discuss your answers with your partner and record them in the area below.

#3 Some satellites orbit over the Earth's poles, but are in rather low, nearly circular orbits. Can you think of reasons why these satellites and orbits might be necessary and useful?

Click here to return to the Lesson Map.