Because at least one asteroid appears to be coated by a thin layer of ice. And just that kind of asteroidal frosting could have been the source of our water here on Earth.

至少有一个行星被一层薄薄的冰层覆盖，这些冰可能就是地球上水的来源。

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These rocks are believed to be the result of an asteroidal prang that happened many millions of years ago and left a crater 460km across, which dominates Vesta's southern hemisphere.

这些岩石据说是几百万年前的小行星碰撞的结果，并在灶神星的南半球形成了一个跨度为460公里的陨石坑。

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These rocks are believed to be the result of an asteroidal prang that happened many millions of years ago and left a crater 460km across, which dominates Vesta's southern hemisphere.

据科学家们认为，这些岩石是发生在好几百万年前的一次小行星碰撞的结果，而且留下了一个独占灶神星南半球460公里宽的陨石坑。

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As Chick points out: Is the lifetime of our own civilization going to be lengthy enough to be able to solve problems of getting off-world fast enough to survive asteroidal extinction?

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Two thousand years hence, Sherwood says hypothesized collections of Asteroidal materials congregating at the Earth-Sun L4 and L5 gravitational equilibrium points would make for building materials to construct a large rotating pancake disk capable of housing thousands of people in the comfort of a free-breathing atmosphere and some form of artificial gravity.

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