Planetary Satellites, Asteroids, Comets and Meteors
نویسنده
چکیده
Asteroids, mainly rocky or metallic bodies in the inner solar system, orbit the Sun in various distinct populations (planet-crossers, main-belt asteroids, trans-Neptunian Edgeworth-Kuiper belt objects, Centaurs in the outer planetary region) between which there are transfers over substantial timescales. For example the main belt is the main reservoir replenishing the Earth-crossing asteroids, the latter being removed on timescales of 100 million years or less (i.e. shorter than the age of the solar system).
منابع مشابه
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