【英语时差8,16】阿瑟克拉克与静止卫星 -下(在线收听) |
But how to do it? After all, heavy machinery can’t just float. Most satellites handle this problem by being blasted into orbit around the planet. But in order to be in orbit, you have to be constantly moving. Can You Think of a Way Around This? How about putting a satellite into orbit both in the same direction as the planet rotates-and at the same speed! The result is a satellite that is, in fact, orbiting the planet. But the ground underneath it turns at the same rate as the satellite orbits, so the satellite is always above the same spot of ground. From our perspective on the earth, a geostationary satellite seems fixed in one spot. Thanks, Arthur! |
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