The greatest concern the authors raise is space debris-pieces of "junk" that orbit the earth, with the potential to cause serious damage if they collide with operational units, including the ISS.

两位作者提出的最大担忧是太空垃圾——环绕地球运行的“垃圾”碎片，如果它们与包括国际空间站在内的运行单位相撞，可能会造成严重损害。

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The greatest concern the authors raise is space debris—pieces of "junk" that orbit the earth, with the potential to cause serious damage if they collide with operational units, including the ISS.

作者提出的最大担忧是太空碎片，即环绕地球的“垃圾”碎片，如果它们与包括国际空间站在内的运行体相撞，将有可能造成严重损害。

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But why does then the moon orbit the earth?

那么为什么月亮绕着地球转呢？

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This meant the Apollo Eight astronauts could fire the rocket that would send them from Earth orbit toward the moon.

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Military officials immediately offered to use the Jupiter to put a scientific satellite into orbit around the Earth.

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The radio waves are measured when the earth is at two points opposite one another in its orbit.

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Cremated human remains were placed in the second stage of the Falcon and will orbit the Earth.

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The silver lapel badge is being given to all UK-born spacefarers who get to orbit the Earth.

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It passed far closer even than the geosynchronous satellites that orbit the Earth, but there was no risk of impacts or collisions.

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