托福听力黄金段子：天文学
In ancient times, many people believed the earth was a flat disc. Well over 2,000 years ago; the ancient Greek philosophers were able to put forward two good arguments proving that it was not. Direct observations of heavenly bodies were the basis of both these arguments. First, the Greeks knew that during eclipses of the moon the earth was between the sun and the moon, and they saw that during these eclipses, the earth's shadow on the moon was always round, they realized that this could be true only if the earth was spherical, It the earth was a flat disc, then its shadow during eclipses would not be a prefect circle; it would be stretched out into a long ellipse. The second argument was based on what the Greeks saw during their travels. They noticed that the North Star, or Polaris, appeared lower in the sky when they traveled south, in the more northerly regions, the North Star appeared to them to be much higher in the sky. By the way, it was also from this difference in the apparent position of the North Star that the Greeks first calculated the approximate distance around the circumference of the earth, a figure recorded in ancient documents says 400.000 stadium, that's the plural of the world stadium. Today, it's not known exactly what length one stadium represents, but let's say it was about 200 meters, the length of many athletic stadiums. This would make the Greek's estimate about twice the figure accepted today, a very good estimate for those writing so long before even the first telescope was invented.
在古代，许多人认为地球是扁平的圆盘。2000多年前;古希腊哲学家们能够提出两个很好的论据来证明它不是。对天体的直接观测是这两种论点的基础。首先,希腊人知道日食期间月球的地球在太阳和月球之间,他们看到这些日食期间,地球的影子在月球上总是圆的,他们意识到,这可能是真的只有地球是球形的,地球是一个平面的圆盘,那么它的影子在日食期间不会是一个完美的圆;它会被拉伸成一个长椭圆。第二个论点是基于希腊人在旅行中所看到的。他们注意到，北极星(北极星)在向南移动时，在天空中出现了较低的位置，在更偏北的区域，北极星出现在它们的天空中。顺便说一下，也正是由于北极星的位置的不同，希腊人第一次计算出了大约在地球周长周围的近似距离，一个在古代文件中记载的数字显示，40万体育场，这是世界体育场的复数。今天，我们还不知道一个体育场到底代表什么长度，但我们假设它大约有200米，是许多体育场的长度。这将使希腊的估计大约是今天被接受的数字的两倍，这对于那些远在发明了第一架望远镜之前的人来说是一个很好的估计。
另外有一则好消息，针对托福备考，