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

大气密度如何随着高度变化？

And Mars' cold temperatures are a serious issue.

低温是一个严重问题。

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

成为真正登陆第一人。

Come and sing along about the planet of Mars.

和我一起唱，关于知识。

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

大气主要由什么化合物构成？

Mars underwent a fairly substantial transformation in its climate.

气候发生了相当大变化。

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

然后降落在两颗卫一卫二。

Some think there was an ocean in the northern hemisphere.

有些人认为在北半球有海洋。

Our next story, though, is about Mars.

然而，我们下一个报道是关于。

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

地球到平均距离是2.25亿公里。

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

这些都是这颗红色行，即特征。

Why should Earthlings care about the composition of Mars?

为什么地球上人要关心成分？

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

也帮助我们了解了 宜居性潜能。

Snickers sold twice as many as Mars.

士力架销量是两倍。

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

想想上一个我们刚刚发送到漫游车。

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

事实上，那一地区是非常寒冷。

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

公转轨道离太阳平均距离略高于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 地球和大小对比。

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

大气很稀薄，不必刻意追求流线型。