But low-Earth orbit isn't a perfect vacuum.

但近地球轨道不是一个完美的的真空。

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In contrast to the mechanism of conduction and convection , radiation may take place in a perfect vacuum.

与传导和对流的原理不同，辐射可在完全真空中进行。

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Until recently most astronomers believed that the space between the galaxies in our universe was a near-perfect vacuum.

直到最近，大多数天文学家都认为我们宇宙中星系之间的空间是近乎完美的真空。

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Among a host of other developmental problems, EUV must operate in a nearly perfect vacuum.

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We were operating in a near perfect vacuum with the temperature well above 200 degrees Fahrenheit with the local gravity only one sixth that of Earth.

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She had trained for enough emergencies to know that beneath almost every sort of raging anxiety there was a calm pocket, a perfect little vacuum in which both thoughts and actions were crisp and clear.

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