英语语法分析

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。

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。

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。