众所周知,我们所居住的太阳系有九大行星,它们都围绕着太阳不停地沿着椭圆轨道进行公转,太阳位于轨道的一个焦点上.与此同时这些大行星也都在围绕自身的自转轴进行自转.这些行星都有近似于球体的形状.这些几乎是九大行星之间显而易见的共同点了.但九大行星各自独有的特点却非常之多,因而也存在各种各样的分类方法. As we all know, there are nine planets in the solar system where we live. They all revolve around the sun and follow an elliptical orbit. The sun is at a focal point of the orbit. At the same time, these large planets are also orbiting their own axis of rotation. Rotation. These planets all have a shape similar to a sphere. These are almost the common points between the nine planets. However, the unique characteristics of the nine planets are very numerous. Therefore, there are also various classification methods. .