translation.en: I'm showing here Venus, Earth and Mars -- three planets in our own solar system that are roughly the same size, but only one of which is really a good place to live.
translation.zh: 我这里展示的是金星，地球和火星－－ 这三颗我们太阳系中的行星基本上大小相同， 而其中只有一颗 适合生命生存。