Light travels at about 300, 000 kilometers per second (186, 000 miles per second) — that's pretty fast.

光速大约为每秒300,000公里(即每秒186,000英里)——非常之快。

youdao

The escape velocity needed by a spacecraft to overcome the tug of Earth’s gravity is around seven miles per second—ie, Mach 34.

宇宙飞船克服地球引力所需的逃逸速度约为每秒7英里（也即34马赫）；

youdao

Claims that it's possible to push light beyond 186, 000 miles per second (300 million meters per second), are equally illusory, Galison said.

声称可能把光速增加到超过每秒186,000英里(每秒300,000千米)，同样也是虚幻的，盖利森说。

youdao

We don't usually do our chemistry calculations in miles per hour, so let's switch that to 42 meters per second, so it's -- sorry, it's 94 miles per hour.

在化学计算中我们很少,用英里每小时，所以我们把它换算为42米每秒，对不起，它是94英里每小时。

麻省理工公开课 - 化学原理课程节选

In fact, they will be moving at four or five miles per second as they approach their targets.

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They shed bubbles of material at speeds of thousands of miles per second, which collide with surrounding dense clouds of hydrogen.

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The first CME is travelling towards Earth at speeds greater than 1300 miles per second, and the second is travelling at about 1100 miles per second.

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