Our solar system 我们的太阳系 takes 花费 225million 两点二五亿 years 年 to rotate around 环绕转圈 the Milky Way. 银河系

The last time Earth was in its current position, dinosaurs were just beginning to roam the Earth. 上一次太阳系在银河系的这个位置时，地球上的恐龙还刚刚开始繁盛。