了解宇宙是如何运行的（2010）

How the Universe Works S08E02

Part 7 Jan. 30, 2022, 2:58 p.m.

必须要这么做，这样它才能自然地
This has to happen so that
it can naturally slide
滑入这个轨道，然后到达火星
into this orbit
and then end up on mars.
如果我们没有达到这个精度
If we miss that precision,
我们可能会被抛向太空
then we just could end up
hurtling out into space.
即使 NASA 达到了他们的目标
Narrator: Even if nasa hit
their target.
宇航员们还有10个月的太空之旅
The crew still has a long
10-month journey in space.
人类的身体根本就不适合
The human body is just simply
not designed
长时间的太空旅行
for long-duration space travel.
太空旅行会破坏骨骼
Narrator: Space travel
can destroy bones,
削弱心脏肌肉，甚至扰乱大脑
weaken heart muscles,
and even mess with the mind.
邮轮能在前往红色星球的旅程中幸存下来吗？
Could a cruise survive
the journey to the red planet?
♪
NASA 计划在本世纪30年代把人类送上火星
narrator:
Nasa plans to put humans on mars
in the 2030s.
火箭技术将被推向极限
Rocket technology will be pushed
to its limits.
但是最大的障碍是在行星之间宇宙飞船里的
But the greatest hurdle
is our own fragile bodies
我们自己脆弱的身体
out there in a spacecraft
between the planets,
所有的赌注都没有了
all bets are off.
这将是一次危险的旅行
It's going to be
a dangerous trip.
欧文:双手放在第四个横档上
Irwin: Both hands down
to about the fourth rung up.
当宇航员詹姆斯·欧文站在月球上时
Narrator:
When astronaut james irwin
stood on the moon,
他的心跳不规则
his heart beat irregularly.
回到地球后，欧文心脏病发作
Back on earth,
irwin suffered heart attacks,
最终死亡
which eventually proved fatal.
2016年的一项研究发现
A 2016 study found
that apollo lunar astronauts
阿波罗登月宇航员
are four to five times
more likely to die
死于心血管疾病的可能性
from cardiovascular disease
是从未离开地球轨道的宇航员的4到5倍
than astronauts
who never left earth's orbit.
一个原因可能是深空辐射
One cause could be
deep-space radiation.
外太空的辐射
And the radiation
in outer space
不仅会损害心脏肌肉
won't just be damaging
the heart muscles
还会损害神经系统
but also the nervous system
和宇航员的大脑
and astronauts' brains
in outer space.
宇航员前往火星将面临
Narrator:
Astronauts heading to mars
will face radiation
恒星核心产生的辐射
created in the core of stars.
一些来自我们的太阳，即太阳喷射出的
Some comes from our sun
when solar ejections
致命的带电粒子流
throw out streams of deadly
charged particles.
♪
还有来自太阳系外的宇宙射线
there are also cosmic rays
from outside the solar system.
这些高能粒子产生于超新星
Created in supernovas,
the death of giant stars,
也就是巨恒星的死亡
these energetic particles
它们以接近光速的速度穿过星系
race through the galaxy at
close to the speed of light.
你不会想过多地接触到它们的
And you don't want to be
exposed to too many of them.
低剂量的话，这根本不是问题，真的
In low doses, it's not a problem
at all, really.
但在足够高的剂量下，这些东西会穿透我们
But in high enough doses,
these things penetrate ourselves
破坏我们的 DNA，长♥期♥下去
and damage our dna
and over the long term
会对太空中的人体造成非常严重的伤害
can cause really bad damage
to human bodies in space.
你在太空待得越久，危险就越大
Narrator:
The longer you stay in space,
the greater the danger.
杜尔达:记住，我们的登月任务
Durda: Remember,
our missions to the moon
只有一两周的时间
were on the order
of a week or two.
登陆火星的任务
A mission to mars,
at the minimum,
至少需要两年
is going to be
something like two
或两年半的时间
or two-and-a-half years,
probably.
这些宇宙子弹可以导致突变，甚至癌症
Narrator:
These cosmic bullets can
cause mutations and even cancer.
2019年的新研究表明
New research from 2019 suggests
space radiation
太空辐射会导致
will cause memory loss
一到三名火星任务的宇航员记忆丧失
in one to three astronauts
on a mission to mars.
达内尔:这不仅仅是
Darnell:
And it's not just a problem
忘记把钥匙放在哪里的问题
of forgetting where
you've left your keys.
试图通过气闸返回时
Trying to come back in through
the airlock, you do not want
你肯定不想忘记紧急程序
to be forgetting
emergency procedures.
所以我们必须认真考虑
So we're going to have
to really consider,
我们如何减轻辐射的影响
how do we mitigate
the effects of this radiation
使人们有可能去火星
to make it possible
for people to go to mars
并在不生病的情况下度过一段时间?
and actually spend some time
without being ill?
所以飞船需要保护宇航员
Narrator: So the ship
needs to protect the astronauts.
普莱特:嗯，你会想，“嗯，我只是想”
Plait: Well, you think,
"well, I would just,
“我不知道是否能用非常厚的铅做一艘宇宙飞船”
I don't know, build a spaceship
out of really thick lead.
嗯，一方面它很重，而且事实证明
Like, well, that weighs a lot,
and it turns out
铅并不能保护你免受这种辐射的伤害
lead doesn't protect you
from this kind of radiation.
你需要别的东西
You need something else.
有一种东西
Well, there is something else
可以保护你不受辐射的伤害
that protects you
from this radiation,
那就是水
and that's water.
我们需要带很多很多的水
We need to bring lots
and lots of water
用来喝和做饭
to drink and cook with.
如果我们把水放在宇宙飞船周围的一层
、And if we just place
that water in a layer
它就能吸收宇宙射线
around our spacecraft,
that can absorb the cosmic rays.
你可能会想，好吧，你喝的水
You might think, well,
you're drinking the very water
正是用来阻止对我们造成损害的辐射
that using to stop the radiation
that's causing damage to us
那喝这水不会很危险吗？
won't the water be dangerous
to drink it?
其实不是这样的
It doesn't really work
quite like that.
你只是把一个高速的亚原子粒子
You're just taking one
high-speed subatomic particle
变成另一种粒子
and changing it into another one
然后被水捕获
as it gets captured
by the water.
幸运的是，水还是可以安全饮用的
Water's still gonna be safe
to drink, fortunately.
但是即使 NASA 可以保护宇航员免受辐射伤害……
Narrator:
But even if nasa can shield
its astronauts from radiation...
……但太空还会引起其他健康问题
...Space causes other
health issues.
你的骨头会开始脱矿
Your bones are starting
to demineralize.
他们会越来越虚弱
They're getting weak.
即使在你年轻力壮的时候你也会得关节炎
You're getting arthritis
even in the prime of your life.
在10个月的旅程中，失重状态
Narrator: Weightlessness
during a 10-month journey
会使宇航员的骨骼变薄