英语趣味科普——人类登陆火星可能会遇到哪些困难?

日期:2020年06月03日 18:37:32 分类: 评论:发表评论 观看: 2,107 次

为什么登陆火星如此困难

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When it comes landing spacecraft on planets, or moons,

当涉及到飞船着陆行星或月球,

or back here on earth-Mars sucks.

或返回地球,火星的情况则完全不同

There's a lower success rate landing on Mars than on Venus,

降落在火星上的成功率要低于金星、

the moon, the earth,

月亮、地球

even Satumn's moon Titan.

甚至是土卫六——泰坦

And in large part,

很大程度上

This is because Mars's atmosphere is in the perfect goldilocks zone

这是因为火星的大气层处于完美的宜居地带

of being a total headache.

这就是问题所在

On the moon(or an asteroid)

在月球(或小行星)上

you can use ightweight spacecraft made essentially out of tinfoil

你可以使用基本上由锡箔制成的轻型宇宙飞船

because there's no air to cause drag or pressure or heat.

因为没有空气形成阻力、压力或造成船体过热

Essentially,

本质上

you save weight not having heat shields or thick walls,

你可以节省隔热蔽或厚壁的重量

but need to use rockets

但需要使用火箭着陆

to land in what's called a "powered descent."

这就是所谓的"利用动力下降"技术

On earth,or Venus, or Titan,

在地球、或金星、或泰坦上

There's enough air that you can land largely unpowered,

有足够的空气你可以尽可能少的使用动力进行着陆,

first by slowing down with a heat shield and atmospheric drag,

首先利用隔热罩和大气阻力进行减速,

and then with parachutes.

然后使用降落伞。

So you use a lot of weight for heat hields and walls and parachutes

因而你会使用较重的隔热蔽和厚壁以及降落伞,

but don't need big rockets or lots of fuel to land.

但不需要巨型火箭或大量的燃料

However,

然而·

the air on Mars is literally the worst of both worlds

火星上的空气其实是所有星球里最糟糕的

Thick enough that you actually have to deal with it with heat shields and walls

有时空气含有量之浓,你须使用隔热蔽和厚壁来处理

but thin enough that it doesn't help you slow down much

但有时空气之稀薄,则不能帮助你有效地减速

and you also need to use rockets

并且还需要使用火箭着陆

Mars is simply a challenging place to land a spacecraft,

火星是一个对登陆航天器来说具有挑战性的地方

which is why we've tried so many different

这就是为什么我们尝试了许多不同的

and crazy techniques for landing there:

和疯狂的技术来着陆火星

we've landed Ianders and rovers using retrorockets,

火星上已经有我们的登陆车和漫游者配备制动火箭

in inflatable bouncy airbags,

加以充气弹性安全气囊

by being lowered from a hovering sky crane

同时使用悬停机慢慢降落

all of which ALSO used heat shieldsand parachutes

这些设备 在着陆最后阶段之前 同样使用隔热蔽和降落伞

and rocket powered descent before the last stage of landing.

以及"动力下降"技术

And space agencies are testing other crazy things

而航空机构正在测试其他疯狂的东西,

like giant supersonic parachutes

如巨型超音速降落伞

and inflatable innertubes around landers to increase their surface area

以及环绕在着陆器上的可充气式缓冲器以增加表面积

and help them slow down more in the thin air before landing

降落前在稀薄的空气中 帮助登陆器有效减速

probably still wifth rockets, or sky cranes).

可能仍旧需要火箭或空中悬停机

Yes, you heard that right

是的, 你听到的没错

It's possible that when the first humans land on Mars,

很有可能 当第一个人着陆火星上时

we may do so in an inflatable donut.

我们或许可以做一个可充气式"甜甜圈"

Or we'll just skim at a really low angle past the tops of mountains

或者我们只需以极小角度掠过山顶

For a really long time to slow down enough

经过很长的时间而将速度降下来

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