Two colleagues and I went out for lunch today and one of them asked what the word 'geosynchronous' meant. It's a term to describe the orbit of a satellite that appears to be stationary over the Earth, we answered, and then we all three pushed our imaginary glasses up the bridge of our noses. We were half right with our explanation. Geosynchronous is a term used to describe the orbit of a satellite that moves at the same speed that the Earth rotates about its axis. However, because this orbit can be titled over the Earth like an angel with a lopsided halo, the satellite can appear to move north and south in the sky throughout the day, though it always stays over the same line of longitude. A geostationary orbit, the one we often think of when we hear the word "geosynchronous," is when a satellite is in a geosynchronous orbit over the equator. In this kind of orbit, the satellite appears to be stationary over the Earth. In the same way that a square is always
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