人究竟能够看多远?拿起一架望远镜,你能够看到40万公里远的月球上的环形山。而位于美国帕洛玛山上的海尔望远镜的威力是如此强大,以至于你不能用它去看像月球“这么近”的物体。天文学家用它来观察夜空中距离地球更遥远的物体。这架直径5米的望远镜能够观察到起出我们视线范围的遥远星体。其中一些星星距离我们是如此遥远,即使以光的速度都要走上几百万年才能到达地球。 How far can one see? Pick up a telescope and you can see the crater on the moon 400,000 kilometers away. And the power of the Haier telescope on Mount Paloma in the United States is so powerful that you can not use it to see objects like the Moon “so close.” Astronomers use it to observe objects in the night sky farther away from Earth. The 5-meter telescope allows the observation of distant stars that take our line of sight. Some of these stars are so far away from us that millions of years have passed to reach Earth, even at light speed.