What is the only terrestrial planet on this list?

以下哪一个是唯一的类地行星？

And this will really help us understand how terrestrial planets are made.

这将真正帮助我们理解类地行星的形成过程。”

But the long era of the four terrestrial planets will be over.

但是四颗类地行星的漫长时代将会结束。

Instead of a mantle, like terrestrial planets, Jupiter has a huge region made up of liquid metallic hydrogen.

不想类地行星有地幔，木星有一大块区域由液态等离子氢构成。

Unlike the other three terrestrial planets, Earth has something very important: Water.

与其他三个类地行星不同，地球有一个非常重要的东西：水。

After earth, Venus is the second largest terrestrial planet, meaning it has a solid rocky surface and an atmosphere.

地球之后，金星是第二大类地行星，这意味着它有着坚固的岩石表面和大气层。

Up in the corner, the terrestrial planets, Mercury, Venus, Earth and Mars.

在角落里，类地行星水星、金星、地球和火星。

The Earth is the largest of the terrestrial planets, the four smaller, denser, rocky worlds orbiting close in to the Sun.

地球是类地行星中最大的一个（距太阳较近的四颗更小、密度更大的岩石行星）。

In the long term, nothing is stopping humanity from constructing a zero-propellent transport network for the terrestrial planets, centered on the Martian moons.

从长远来看，没有障碍会阻挡人类建立一个零推进剂的运输网络，连接着以火星卫星为中心的陆地行星。

Though natural disasters have rocked our terrestrial planet, life on Earth has survived, evolved, and flourished for billions of years.

尽管自然灾害震撼了我们的地球，但地球上的生命已经生存、进化并繁荣了数十亿年。