If the rocket does not reach this speed, it will fall back to the earth.

如果达不到这个速度，火箭会落回地球。

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These oxides are released into the atmosphere and they can fall back to earth as acid rain.

这些氧化物会被排进大气，然后会以酸雨的形式降回地面。

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The pilot would then experience about a minute and a half of zero-G before the spacecraft begins to fall back to Earth.

然后在返回地球之前，飞船将进行一分半钟的零重力飞行试验。

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The ISS has a tendency to fall back to Earth over time as it drags through the top of the atmosphere.

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The problem is that the rocket ships almost always disintegrate in the atmosphere on their ascent to the heavens and fall back to earth.

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Disney, which was flying high last week with Up and The Proposal, is expected to fall back to earth.

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