And that could definitely have happened on Mars and Venus.

而这在火星和金星上也极有可能发生。

It ends up keeping those objects from the inner solar system, where Earth and Mars and Venus are.

它处死来自太阳系内部的物体，那里有地球，火星和金星。

Why are there so many efforts to map out other planets like Mars and Venus when we haven't followed map out our own.

为什么我们要费那么大劲去绘制火星和金星等行星的地图，而却还没有探索完我们自己的星球呢？

I knew very well that except for the huge planets like Earth, Jupiter, Mars, and Venus, which have been given names, there are hundreds of others that are sometimes so small that it's very difficult to see them through a telescope.

我很清楚知道，除了地球、木星、火星、金星这几个我们已经命名的大行星外，还有几百个别的星球，它们有的非常小，就是用望远镜都很难看到。