古代罗马人相信这种石头是掉到地球上的星星的碎片。
The Ancient Romans believed that the stones were splinters of stars that had tumbled to earth.
这是幸运的对于地球上的所有生命——因为正是因此才让星星们闪耀了数十亿年——但它造成了一个聚变燃料很难加以利用。
That's fortunate for all life on Earth — because that's what allows stars to shine for billions of years — but it does make it a very difficult fusion fuel to utilize.
这些窗口还能够帮助舱内人员为自己定位——空间上的和心理上的——根据地球，月亮和星星的位置。
The Windows allow the crew to Orient themselves-spatially and emotionally-to the Earth, the Moon, and the stars.
他们的理论是，这颗星星的轨道每隔2600万年都会进入奥尔特星云所在的区域，从而激发该处的彗星冲击到地球上。
Their theory was that the orbit of this star every 26 million years moved into an area called the Oort cloud and dislodged comets that then pounded the earth.
我们可不能失去这些，地球上的小星星。
为了提醒自己这一点，在你的办公室里摆一张图片(一张在太空里，或漫天星星的夜里，或是海洋上拍摄的地球图片)，当你感到不知所措时，就看看它们。
To remind yourself of that, keep a picture in your office-the earth taken from space, a starry night or the ocean-and look at it whenever you feel overwhelmed.
但是不巧的是，在地球这个行星星球上，这种事不会发生，因为“恒星年（由365又1/4天所组成）是非十进制的”这一事实是确凿无差的。
Unfortunately, here on planet Earth, with its decidedly undecimal sidereal year of 365-and-a-quarter days, that is just not going to happen.
这就是超新星，从地球上看原本没有星星(者是一颗很黯淡的星)地方出现了一个明亮的新星。
This is a supernova, which when seen from Earth, appears as a bright new star in a place where none (or only a very faint star) appeared to be before.
天上的无数闪亮的星星，每颗星代表地球上每个人的一颗星星，代表着全人类的希望。
The countless shining stars in the heavens, one star for each person on earth, represents the hope of all mankind.
和地球上同名的动物相似，随着蝌蚪星系年龄的增加，它的尾巴很可能也会消失，而位于长尾的这些星团，会聚集成这个大螺旋星系的小卫星星系。
Following its terrestrial namesake, the Tadpole galaxy will likely lose its tail as it grows older, the tail's star clusters forming smaller satellites of the large spiral galaxy.
诸多细如蛛丝的线将地球上的每个大城市相连接，让这些城市如星星般闪耀。
Gossamer -thin threads linked every major city on the planet. The cities shone like stars.
空气的不存在，也说明了为什么在空中星星看来并不闪烁，而不像从地球上看的那样。
The absence of air also explains why the stars do not seem to twinkle in space as they do from the earth.
（高二册，第198页）太空中没有空气，这也说明了为什么在太空星星看来并不闪烁，不想从地球上看到的那样。
The absence of air also explains why the stars do not seem to twinkle in space, as they do from the earth.
（高二册，第198页）太空中没有空气，这也说明了为什么在太空星星看来并不闪烁，不想从地球上看到的那样。
The absence of air also explains why the stars do not seem to twinkle in space, as they do from the earth.
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