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发帖数: 1994 | 1 The Satellites that Surround Earth
Illustration Credit: P. C.-W. Fu & A. Hanson (Indiana), P. Frisch (Chicago), NASA
Explanation: Thousands of satellites orbit the Earth. Costing billions of dollars, this swarm
of high altitude robots is now vital to communication, orientation, and imaging both Earth
and space. One common type of orbit is geostationary where a satellite will appear to hover
above one point on Earth's equator. Geostationary orbits are very high up -- over five times
the radius |
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