How does the Martian atmosphere's density change at different elevations?

火星大气密度如何随着高度变化？

And Mars' cold temperatures are a serious issue.

火星低温是一个严重问题。

Alyssa has dreamed of being the first person to actually land on Mars.

成为真正登陆火星第一人。

Come and sing along about the planet of Mars.

和我一起，火星知识。

The atmosphere of Mars is made primarily of what chemical compound?

火星大气主要由什么化合物构成？

Mars underwent a fairly substantial transformation in its climate.

火星气候发生了相当大变化。

Later flights will land on Deimos, one of Mars' two moons.

然后降落在火星两颗卫星之一火卫二。

Some think there was an ocean in the northern hemisphere.

有些人认为在火星北半球有海洋。

Our next story, though, is about Mars.

然而，我们下一个报道是火星。

The average distance from Earth to Mars is 225 million kilometers.

地球到火星平均距离是2.25亿公里。

These are all features of the red planet, aka, Mars.

这些都是这颗红色行星，即火星特征。

Why should Earthlings care about the composition of Mars?

为什么地球上人要心火星成分？

Our most recent rover on Mars has discovered traces of organics.

也帮助我们了解了 火星宜居性潜能。

Snickers sold twice as many as Mars.

士力架销量是火星两倍。

So think about the last rover that we just sent to Mars.

想想上一个我们刚刚发送到火星漫游车。

And that part of Mars is a very cold place, indeed.

事实上，火星那一地区是非常寒冷。

It orbits on average a little over 200 million kilometers from the Sun.

火星公转轨道离太阳平均距离略高2亿公里。

The former Soviet Union is the only other country to land a rover on Mars.

前苏联是唯一一个将探测器送上火星国家。

This picture actually represents the true size of Mars compared to Earth.

这张照片真实反应了 地球和火星大小对比。

Mars' atmosphere is so thin, you don't need a lot of streamlining.

火星大气很稀薄，不必刻意追求流线型。