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(单词翻译:双击或拖选)
Vesta is quite far away. Like many asteroids1, it has an orbit out between the orbits of Mars and Jupiter. Astronomers2 first spotted3 it when looking for a new planet they thought should exist between these two. As I said, Vesta is quite small–about three hundred and twenty-five miles across. So if it’s small and far away, how come we can see it from here? Vesta’s surface has a coating of pyroxine and olivine, two minerals that are actually also spewed up by volcanoes here on earth. They give it a whitish exterior4 that reflects well, making it just possible to see Vesta with your eyes, even when the only two larger asteroids, Ceres and Pallas, are completely invisible.
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1
asteroids
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n.小行星( asteroid的名词复数 );海盘车,海星 | |
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2
astronomers
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n.天文学者,天文学家( astronomer的名词复数 ) | |
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3
spotted
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adj.有斑点的,斑纹的,弄污了的 | |
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4
exterior
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adj.外部的,外在的;表面的 | |
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