The terrestrial planets are mostly rocks: dense rocky and metallic material, with minor amounts of gases.
类地行星主要是岩石:密度大的石块和金属物质,同时会有少量的气体。
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Asteroids are minorplanets, most of which circle the sun in a region known as the asteroid belt, between the orbits of Mars and Jupiter.
小行星是较小的行星,它们中的大部分在火星和木星轨道间的小行星带中环绕太阳运行。
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For the main part, that's it for the solar system — including a whole host of satellites orbiting the main planets and countless minorplanets (including Pluto) and comets.