了解宇宙是如何运行的（2010）

In just over 28 years,
航♥天♥员在有生之年就能抵达目的地
Well within the lifetime of its human payload.
现在 这个点子听起来很棒吧
Now, this sounds like a great idea, right?
只需要很多反物质
Let's get together a lot of antimatter.
让我们来制♥造♥一些反物质
Let's create some antimatter,
将它和物质结合起来
And let's combine it with regular matter,
就可以产生庞大的能源
And we have this outstanding energy source.
但反物质有一个巨大的缺点
But antimatter has a huge problem,
正好也是它的优点
And that is exactly what its advantage is ...
反物质和物质相遇 会相互湮灭产生能量
When it meets matter, it's going to annihilate and create energy.
将一磅（0.45公斤）的反物质
Fill a conventional fuel tank
装进传统的燃料槽
With a single pound of antimatter,
这样肯定会爆♥炸♥
And you'll get an explosion
威力超过广岛原♥子♥弹♥的一千倍
More powerful than 1,000 hiroshima bombs.
反物质像烫手山芋一样难以处理
Antimatter is just too hot to handle.
我们需要一个可靠的能源来源
We need a reliable energy source
每次产生的能量足以让飞船用好几年
That can power our starships for years at a time.
目前只有几种技术办得到
And there are only a few candidates that can do this.
其中之一就是核能
Among them, fusion power ...
也就是利用太阳本身的能量
Harnessing the power of the sun itself.
在高温 高密度的太阳核心中 氢原子发生碰撞
In the sun's hot, dense core, hydrogen atoms collide...
撞击强到使它们合而为一
...Smashing into each other with such force
释放出巨大的能量
They fuse, releasing enormous amounts of energy.
这是核聚变
This is nuclear fusion.
进行太空旅行时
What we want to do in space travel
我们希望将核聚变设备做到最小
Is miniaturize it and put it in a spacecraft
并使用它来作为太空探测
And use that as your power system
宇宙飞船推挤系统的动力
And as your propulsion system for deep-space exploration.
核聚变火箭的速度
A fusion rocket
仍然有反物质火箭的三分之二
Is still two-thirds the speed of one powered by antimatter.
最重要的是它的燃料氢气
And best of all, its fuel, hydrogen gas,
在恒星之间的广大云层里到处都是
Can be found in vast clouds in the space between stars.
宇宙飞船可以在外层空间
It would simply automatically fire in outer space
使用星际气体产生动力
Using interstellar gas.
并且 理论上它永远不会需要加油
And, in principle, it would never require refueling.
使用核聚变动力的太空方舟
Our fusion-powered space ark heads for its first target,
能以光速的10% 前往第一个目的地南门二
Alpha centauri, at 10% the speed of light.
这趟旅程需要42年才能完成
It will take 42 years to complete the journey,
宇宙非常必须把人类先锋
And its precious load of human pioneers
平安地运到那里
Must be delivered safe and well.
但这趟旅程充满了杀机
But the crossing may be deadly.
残暴的宇宙有无数种杀人手法
Our violent cosmos has a million ways to kill.
巨大的太空方舟发动了核聚变火箭
A giant space ark fires its fusion rockets.
船上是成千上万的志愿者
Inside the ship are thousands of human volunteers.
这趟旅程的志愿者要殖民到遥远的星系
They're on a one-way mission to colonize a distant planet.
未来 这趟旅程是非走不可
One day, we will have to make this journey.
这是不可避免的
It's inevitable that we go off-planet.
这样人类才能延续命脉
I think we're gonna have to do it to survive as a species.
太空方舟的第一个目标
The ark's first target
是距离太阳最近的恒星系南门二
Is the closest star system to the sun, alpha centauri.
这趟征途需要40年的漫长时间
And the journey will be long ... Around 40 years.
保持船员身体健康是必要的
Keeping the crew fit and healthy is imperative,
但是这并不容易
But it won't be easy.
人体在太空
A lot of things happen to the human body
会出现很多状况
When you go into space.
当你失重的那一刻
The moment you become weightless,
马上就会觉得头很胀
You instantly get kind of a full-headed feeling.
你会感到头晕 恶心想吐
You get dizzy. That can make you feel nauseous.
焦立中在国际空间站
Leroy chiao spent six months
待过六个月
On the international space station,
有足够的时间来体验
Long enough to experience
零重力的破坏力
The damaging effects of zero gravity.
你的骨头感觉不到碰撞
Your bones aren't feeling any impact,
所以你的身体认为不需要骨骼
So your body decides it doesn't need bones anymore,
骨头的矿物质会开始流失
And it'll begin to de-mineralize your bones.
然后（由于零重力）你不会用到肌肉
And then, your muscles, through disuse ...
所以它们当然会快速萎缩
Of course, they'll naturally atrophy very quickly.
人类是在地球引力下演化出来的
The human body evolved to live with earth's gravity.
在没有引力的太空
Without it,
每个月骨骼都会损失2%的质量
Bones lose 2% of their mass for every month spent in space.
心血管系统也会受创
The cardiovascular system suffers, too.
体液会在体内堆积
Body fluids pool.
心跳速度和血压都会升高
Heart rate and blood pressure rise.
阻力训练有助于减轻症状
Resistance training helps reduce the symptoms.
我们在太空站每天运动两个小时
We're scheduled for two hours of exercise a day
保持我们的心血管系统
On the space station to keep our cardiovascular system fit,
和我们的骨骼的健康
To keep our muscles and our bones fit.
运动可以减缓危险的流失过程
Exercising can hold off the dangerous wasting process.
但在长达42年的南门二旅程中
But a 42-year journey to alpha centauri
如果没有重力将是致命的
Without gravity would be fatal.
显然我们需要一个永久性的失重解决方案
Obviously, we need a permanent solution to weightlessness.
随着科技的发展 在不久的将来
There's nothing to prevent us, in the near future,
我可以制♥造♥人造重力
From creating artificial gravity.
办法就是离心力
The answer is centrifugal force.
离心力
It's the force
可以让摩托车车手或者云霄飞车乘坐着
That sticks daredevil bikers to vertical walls
待在垂直的墙面上或寻求刺♥激♥
And keeps thrill-seekers glued to their seats in theme parks.
旋转会产生这种向外的力量
Rotation produces this outward force,
在宇宙飞船中创造离心力将相对简单
And creating it in a spaceship would be relatively simple.
只要旋转太空舱
By rotating a space capsule,
里面的宇航员就会
It means that the astronauts inside
体验到人造重力
Will experience artificial gravity.
以恰当的速度旋转生活舱
Spinning the living quarters at just the right speed
将延缓骨骼流失和肌肉萎缩
Will hold off bone and muscle wasting.
但是低重力其实是
But as they journey deep into space,
人类先锋在深入太空时面临的最小威胁
Low gravity is the least of the dangers our pioneers will face.
最难克服的应该是辐射
Radiation is probably the biggest challenge.
我们会暴露在更强烈
We're gonna be exposed to much harsher levels,
更大量的辐射之下
Much higher levels, of radiation.
太阳表面会不断喷出
The sun's surface shoots out
危险的带电粒子流
A constant stream of dangerous charged particles,
质子和电子
Protons and electrons
以每小时160万公里的速度喷出
Traveling at close to a million miles an hour.
它们会破坏你的DNA
These things will break your dna.
会导致癌症 还会要了你的命
They'll cause cancer, and they will kill you.
在我们头顶上的
The earth's magnetosphere
地球磁场和大气层
And the atmosphere above our heads
保护我们免受太阳辐射的严重伤害
Protects us from the worst of this radiation.
但远离地球的人类先锋
But far from the earth,
将直接暴露在辐射之下
The pioneers will face radiation head-on.
这是最大的技术障碍
That really is the biggest technical barrier
如果要让人类深入太空探索
To mankind sending people out farther and deeper into space.
问题不在于推进系统 计算机或导航系统
It's not propulsion. It's not computers or navigation.
而是如何维持航♥天♥员的健康
It's how do we keep people healthy?
在我们的太阳系之外
Beyond the boundary of our solar system,
辐射的威胁更为严重
The radiation threat gets worse.
带电粒子以更快的速度冲向你
Charged particles come at you even faster.
在某些情况下 单一质子
In some cases, there are single protons
蕴含着很大的力量
That actually pack as much of a punch
其威力相当于时速160公里的皮球
As a 100-mile-an-hour fastball.
这些宇宙射线还有一个更加致命的力量...
These cosmic rays are joined by an even deadlier force ...
由最暴♥力♥的宇宙事件产生的伽玛射线
Gamma rays, blasted out by violent, cosmic events.
所有的宇宙现象 从恒星爆♥炸♥
All of the cosmic phenomena, from stars exploding...
到黑洞吞食星系的大部分区域
...To black holes eating up large parts of galaxies...
都会产生
...Produce radiation
能量高的吓人的辐射和粒子
And particles that are incredibly energetic.
你从没有见过这些粒子
You've never seen these particles before.
你的身体从未适应它们
You body's not adapted to them.
而且它们会携带很强的能量
And they come at you all the time,
不停冲向你
And they're very high-energy.
星系宇宙辐射