Scientists believe Ceres is made of rock, and covered with ice.

科学家认为谷神星是岩石构成的，上面覆盖着冰。

Ceres is the biggest, at about 900 km across.

谷神星是最大的，直径约900公里。

Scientists want to study whether Ceres was ever home to microbial life.

科学家们想要研究谷神星是否曾经是微生物的家园。

The object was given the name Ceres… but was it really a planet?

这个物体被命名为谷神星… … 但它真的是一颗行星吗？

Hopes were high that Ceres was the wished-for planet between Mars and Jupiter.

谷神星曾被寄予厚望，人们认为它就是预想的火星和木星之间的那颗行星。

But Ceres isn't the only world in our solar system whose development was cut short.

但谷神星并不是太阳系中唯一一个发展中断的星球。

It will also try to discover how Ceres' surface has changed.

它还将试图找出谷神星表面如何变化。

Ceres probably has a rocky core surrounded by a water ice mantle.

谷神星可能有一个岩石内核，被水冻冰块所覆盖。

Almost all asteroids are irregularly shaped, although a few big ones, like Ceres, are nearly spherical.

几乎所有的小行星都是不规则形状的，尽管有几个像谷神星这样的大小行星几乎是球形的。

Originally, asteroids were named after female goddesses; Ceres, Vesta, Juno, and so on.

最初，小行星是以女性女神的名字命名的：谷神星（刻瑞斯）、灶神星（维斯塔）、朱诺，等等。