But 8 km/s is blisteringly fast. When youlook at the sky near sunset, you can sometimes see the ISS go past . . . andthen, 90 minutes later, see it go past again. In those 90 minutes, it 8217;s circledthe entire world.
但每秒8千米的速度是非常非常非常快的。如果你在日落时仰望天空，有时候你会看到国际空间站从你眼前飞过……然后过了90分钟，它又出现了。也就是说国际空间站在这90分钟时间里绕地球飞行了整整一圈。
The ISS moves so quickly that if you fireda rifle bullet from one end of a football field, the International SpaceStation could cross the length of the field before the bullet traveled 10yards.
如果你想和国际空间站比飞行速度的话，假设你在足球场的一端射出一颗来复枪子弹，当国际空间站跑到足球场的另一端时，子弹才刚飞了不到10米。
Let 8217;s imagine what it would look like ifyou were speed-walking across the Earth 8217;s surface at 8 km/s.
想象一下你以每秒8千米的速度在地球表面竞走会是什么样子。
To get a better sense of the pace at whichyou 8217;re traveling, let 8217;s use the beat of a song to mark the passage of time.Suppose you started playing the 1988 song by The Proclaimers, “I 8217;m Gonna Be(500 Miles).” That song is about 131.9 beats per minute, so imagine that withevery beat of the song, you move forward more than 2 miles.
为了让你有更直观的感受，我们不妨以歌曲的节拍来记录时间。假设你在开始时播放了1998年普罗克莱门兄弟演唱的I 8217;m Gonna Be（500 Miles）（我要走五百英里），这首歌每分钟大约有131.9拍，所以歌曲每播放一个节拍，你就能走上2英里多。
In the time it took to sing the first lineof the chorus, you could walk from the Statue of Liberty all the way to theBronx.
当你唱完歌词的第一行时，你就已经从布朗克斯（纽约最北端）走到了自由女神像那儿了。
You 8217;d be moving at about 15 subway stopsper minute.
相当于你每秒能跑15个地铁站。
It would take you about two lines of thechorus (16 beats of the song) to cross the English Channel between London andFrance.
当你唱完第二行（16拍）时，你就能够跨越英吉利海峡了。
The song 8217;s length leads to an odd coincidence.The interval between the start and the end of “I 8217;m Gonna Be”is 3 minutesand 30 seconds, and the ISS is moving at 7.66 km/s.
而这里有一个很神奇的巧合。歌曲一共有3分30秒长，而国际空间站的速度是每秒7.66千米。
This means that if an astronaut on the ISSlistens to “I 8217;m Gonna Be,”in the time between the first beat of the song and the final lines. . .
这意味着如果国际空间站上的一位宇航员在听这首歌，那么在整首歌唱到最后一行时……
. . . they will have traveled just aboutexactly 1000 miles.
……他刚好跨越了约1000英里的距离。
1 Specifically, low Earth orbit, which iswhere the International Space Station is and where shuttles could go.
1．这里是指国际空间站或者航天飞机所在的近地轨道。
2 The X-15 reached 100 km on two occasions,both when flown by Joe Walker.
2．X-15曾两次飞到太空，皆由约瑟夫•沃尔克驾驶。
3 Make sure to remember to steer up and notdown, or you will have a bad time.
3．记得是往上拉机头，而不是往下，否则你就要悲剧了。
4 It 8217;s a little less if you 8217;re in thehigher region of low Earth orbit.
4．如果是在近地轨道较高处的话这个数字会小一些。