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发帖数: 1994 | 1 Our Busy Solar System
Explanation: Our Solar System is a busy place. Although the major planets get the most
press, a swarm of rocks, comets, and asteroids also exist. The above plot shows the placement
of known inner Solar System objects on 2002 July 20. The light blue lines indicate the orbits of
planets. The green dots indicate asteroids, officially known as minor planets. The red dots
indicate asteroids that come within 1.3 Earth-Sun distances (AU) of the Sun and so pose an
increased (althou |
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