晴朗无月的夜晚,站在空旷的地方,你就会看见繁星闪烁在黑暗的天空里。如果你不断地观看天象,就会发现星星从东方升起,慢慢地掠过天空,再落于西方,正和我们每天所看见的太阳从东升西落一样。其实,也就是由于地球自西向东自转的结果。因此,对于我们居住在北半球的人来说,总是有一部分南极的星座是看不见的,就象南半球的居民也无法看到北半球的一部分星座一样。由于地球自转轴的北端总是指向北极,所以北半球天空中的星星都是围 Clear moonless night, standing in the open area, you will see the stars flashing in the dark sky. If you keep watching the sky, you will find the stars rising from the east, slowly passing the sky and then the west, just as the sun we see every day from east to west. In fact, that is, the result of the Earth’s rotation from west to east. Therefore, for those of us who live in the northern hemisphere, there are always some Antarctic constellations that are invisible, just as residents in the southern hemisphere can not see a portion of the constellations in the northern hemisphere. Since the northern end of the Earth’s axis of rotation always points to the North Pole, the stars in the sky in the northern hemisphere are surrounded