了解宇宙是如何运行的（2010）

How the Universe Works S03E06

Part 6 Dec. 22, 2021, 6:46 p.m.

For Asteroids Of Just The Right Size.
但是核弹有可能让事情变得更加糟糕
But A Nuclear Bomb could Just Make A Bad Situation Worse.
小行星会被
Transforming An Asteroid
炸成大块的辐射碎屑
Into Large Radioactive Chunks
造成范围更广的破坏
That Rain Down All Over The Planet.
但是还有其他科技手段
But There Are Also Techniques,
比如说把激光或阳光打在小行星上
Like Shining A Laser On The Asteroid Or Sunlight,
这样就能造成所谓的人工彗星喷射流
Which Would Create An Artificial Cometary Jet,
把小行星上面的
If You Will, Would Vaporize Some Of The Water
水和矿物质蒸发掉一部分
And The Minerals On The Surface Of That Asteroid
再把它轻轻地推开
To Gently Push It Off To The Side.
还有一种很棒的方法
Another Fantastic Technique, A Very Robust One,
叫做引力牵引
Is Something We Call The Gravity Tractor.
只要把和卫星
You Just Park A Spacecraft,
一样质量的宇宙飞船
The Mass Of A Communication Satellite,
停在小行星旁边
Next To That Small Asteroid
再让宇宙飞船用推进器
And Use The Thrusters On The Spacecraft
盘旋在小行星的表面上方
To Keep It Hovering Just Off The Surface Of The Asteroid,
接着使用两者之间的引力当做拖绳
And That Uses Then Gravity Between The Two As A Tow Line
轻轻地将小行星拖到旁边
To Move The Asteroid Ever So Gently Off Course.
目前
Right Now
这些科技都还在计划阶段
These Technologies Are Still On The Drawing Board.
就算它们能够成真
If They Do Become A Reality,
也需要数月到数年的时间来准备
We'd Still Need Months Or Years To Prepare.
流浪行星冰期
Rogue Planets, Ice Ages,
伽玛射线暴
Gamma-ray Bursts,
火山爆发
Volcanic Eruptions,
还有小行星撞击
And Asteroid Strikes.
我们熬过了宇宙最残酷的攻击
We've Survived The Worst The Universe Can Throw At Us,
但是人类终究还是要灭亡
But Our Species Will Still Face Extinction.
就像日出一样无可避免
It's As Inevitable As The Sun Rising.
在宇宙中毁灭性攻击的战争中
In A Cosmic Battle To The Death,
我们都是幸存者
We Are The Survivors,
但是宇宙最终还是会赢
But Eventually The Universe Will Win
我们将面临灭顶之灾
And We Will Face Extinction...
给与我们生存资源的太阳
Threatened By The Very Thing That Gives Us Life
让我们也身处危险之中
Our Creator, The Sun.
我们绕行的太阳是个超级大核弹
We Orbit A Giant Nuclear Bomb, The Sun,
但是它并不会爆♥炸♥
But, You Know, It's Not Going To Explode.
因为它的体积太小了
It's Too Small To Explode,
但其实太阳
But What Happens With The Sun Is That Every Day,
是在一天天地慢慢膨胀的
It's A Little Bigger Than It Was The Day Before.
自从太阳诞生后
Since The Sun's Birth,
氢就一直在太阳核心聚变为氦
Hydrogen Has Been Fusing Into Helium In The Sun's Core.
随着氦不断累积核心密度变高
As The Helium Accumulates, The Core Gets Denser.
每秒都有一亿五千万吨♥的氦
With 150 Million Tons Of Helium
被压进太阳核心
Squeezing Into The Core Every Second,
气体受到压缩温度上升
The Gas Compresses And Heats Up.
目前太阳核心内部的温度
Right Now The Temperature Inside The Sun's Core
是华氏2700万度（约1500万摄氏度）
Is 27 Million Degrees,
而且还会越来越热
And Its Getting Hotter All The Time.
气体受热会有什么变化
What Happens When You Heat Up A Gas?
它会膨胀而太阳就是这样
It Expands, And So That's What The Sun Is Going To Do.
太阳膨胀时会变亮
As The Sun Swells, It Will Appear Brighter.
20亿年后
In 2 Billion Years,
太阳会变亮15%左右
The Sun Will Be About 15% Brighter
这样一来
And That Will Lead
如果地球还在现在的轨道
If The Earth Remains In Its Present Orbit
就肯定会出现失控的温室效应
Inevitably To A Runaway Greenhouse .
海洋会蒸发
The Oceans Will Evaporate,
地表的温度可能会升高到
And The Surface Temperature Of The Earth
华氏1000度（约540度）
Could Easily Be A 1,000 Degrees.
如果我们什么也不做
So, If We Don't Do Anything,
20亿年后我们都会被烤焦
In 2 Billion Years, We'll Be Toast.
要是到时候我们还在地球上就难逃一死
If We're Still Here On Earth, We'll Perish.
其他更强韧的生物或许会适应环境的变化生存下去
Other Tougher Species May Find A Way To Adapt And Survive,
但是它们的时日也不多了
But They'll Be Living On Borrowed Time.
太阳会占据整个天空
It's Gonna Fill Up The Sky.
放眼望去
From Horizon To Horizon,
天空都会烧起来
The Sky Will Literally Be On Fire.
50亿年后
5 Billion Years From Now
太阳会耗尽氢
The Sun Runs Out Of Hydrogen
进入它生命中最后的浩劫阶段
And Enters The Final Apocalyptic Stage Of Its Life,
它会膨胀成现在的100倍
Bloating To 100 Times Its Current Size.
我们的太阳会变成怒气冲冲的红巨星
Our Life-giving Sun Is Now An Angry, Red Giant.
红巨星十分庞大
The Red Giant Stars Are So Big
它会吞没自己的行星
They Will Actually Eat Up Their Own Planets.
我们知道有的红巨星
We Know Of The Examples Of Red Giants That Go
膨胀的距离等于在我们太阳系里
All The Way Out To Where The Orbit Of Jupiter Is
膨胀到木星的轨道
In Our Solar System.
太阳不会膨胀到那么大
The Sun Will Not Get Quite That Big,
但是应该会膨胀到火星那里
But It'll Probably Get About Out To Mars.
最后太阳会变得非常大
And Eventually, In Fact, The Sun Will Be So Large
地球就会位于太阳内部
That The Earth Will Be Located Inside Of The Sun,
那个地方肯定不会很舒服
Which Certainly Won't Be A Very Pleasant Place To Be.
红巨星胀大的身体吞没了地球
The Red Giant's Bloated Body
把我们的行星蒸发掉
Absorbs The Earth, Incinerating Our Planet
剩下垂死恒星里的气体和尘埃
Until Its Nothing More Than Gas And Dust Inside A Dying Star.
太阳之死
The Death Of The Sun
是终极大灭绝事件
Is The Ultimate Mass-extinction Event.
这个事情绝对会发生
There's 100% Chance It Will Happen.
它绝对会摧毁我们的星球
A 100% Chance It Will Destroy Our Planet
以及里面的残存的生物
And Any Life Left On It.
然而地球生命
But Life On Earth May Not Be
或许不是太阳系唯一的生命
The Only Life In The Solar System.
太阳变亮以后
As The Sun Brightens,
适居地带会往外迁移
You Can Imagine A Wave Of Habitability Going Out.
现在的适居地带是地球将来是火星
So Right Now It's On Earth, It'll Go To Mars,
然后是木星还有它的卫星
And It'll Go To Jupiter, And Its Moons.
科学家认为木卫二
Scientists Think Jupiter's Moon Europa
或许已经有外星生命
May Already Harbor Alien Life
活在冰冻地壳下方的液态深海
In A Deep, Liquid Ocean Beneath Its Frozen Crust.
木星会变暖
But Out At Jupiter, It'll Be Much Warmer
但是不会热到摧毁一切
But Not So Warm That It Would Destroy Everything.
所以就算地球毁灭了如果木卫二上有生命
So Even When The Earth Is Gone, If There's Life On Europa,
它应该能活下来
It May Be Able To Endure That.
人类还能延续下去吗
But Will Our Species Go On?
没了地球我们能不能存活
Can We Survive The Loss Of Our Home Planet?
宇宙就像个生态系
The Universe Is Like An Ecosystem
生命会根据
Living Things Are Gonna Survive
适者生存的原则活下去
Based On The Law Of Survival Of The Fittest.
适应这个宇宙的关键
What Decides If You're Fit In This Universe
就在于能不能离开自己的星球
Is If You're Able To Leave Your Planet
移居到别的行星
And Go Out And Populate Other Planets.
所以只有能够离开自己星球的物种
So The Only Species That Are Gonna Live On Forever
才能延续下去
Are The Ones That Leave Their Planet.
我们无法掌控宇宙
We Can't Control The Universe,
但我们或许可以掌控自己的命运
But We May Be Able To Control Our Fate.
长远来看
Inevitably, In The Long Term,
地球终究会变得无法居住
The Earth Is Gonna Become Uninhabitable.
这是宇宙运行的道理
It's Just The Way The Universe Works.
宇宙不是为我们打造的它不会在乎我们的诞生
It Wasn't Made For Us, It Doesn't Care That We Exist,
自然也不会管我们是否灭亡
And It Won't Care When We Go Away.
只有我们会在乎自己
The Only People Who Care About That Are Us,
或许我们可以设法自救
And We Might Be Able To Do Something About It.
这么说来我们还有机会活下去
In That Sense, We Have A Fighting Chance.
智慧使我们最大的资产
Our Intelligence Is Our Greatest Asset.
这是40亿年的灭绝于演化
It's The End Result Of Four Billion Years
所造成的结果
Of Extinction And Evolution.
它或许能让我们做到
And It May Give Us A Chance To Do Something
以前物种做不到的事情