了解宇宙是如何运行的（2010）

How the Universe Works S05E05

Part 5 April 18, 2021, 7:47 p.m.

之所以奇怪，是因为，首先
It's weird because, first of all,
它在银河系中移♥动♥得非常快
it is moving extremely rapidly through the galaxy,
比它在轨道上可能的移♥动♥速度
way faster than it could possibly be moving
要快得多
if it's just simply in orbit.
有东西重重地踢了他一下
Something gave it a huge kick.
另外还有一些不寻常的地方
But it's got something else unusual about it as well.
这是一颗很像太阳的恒星
It's a star much like the sun,
但它似乎含有大量的碳
but it seems to have a lot of carbon in it,
这很不寻常
and that's unusual.
类太阳恒星只有在其生命周期的
Sun-like stars only produce carbon
最后阶段才会产生碳
at the end of their life cycle,
即当它们膨胀形成红巨星的时候
once they've swollen up to form red giants.
但这颗还在燃烧着它的氢
But here was a star that was burning through its hydrogen
且生命周期正处于正常阶段的恒星
in the regular part of its lifetime
表面竟然覆盖着碳
covered with carbon.
那里发生了什么事？
What happened there?
科学家们现在相信，这颗富含碳的逃逸恒星
Scientists now believe the carbon-rich runaway star
一定曾经是一个吸血鬼，被锁在一个非常近
must have once been a vampire locked in a very close,
非常快的双子星伙伴关系中
very fast binary partnership
伙伴是一个更大的超级巨星
with a much larger supergiant star.
“吸血鬼”从它膨胀的巨大伙伴那里
The vampire sucked carbon-rich gas
吸走了富含碳的气体
from its bloated giant partner,
但这颗红色超巨星不甘心成为牺牲品
but the red supergiant was a reluctant victim
在一个巨大的爆♥炸♥中成为超新星
and exploded in a vast supernova.
爆♥炸♥的力量本应把吸血鬼摧毁
The force of the blast should have taken the vampire out,
但它的轨道速度太快了
but its orbital speed was so great,
以至于这颗碳染的恒星被甩到了宇宙深空
this carbon-stained star was flung away into space.
这两颗恒星绕着对方快速旋转
These two stars are going around each other quite rapidly.
当其中一个爆♥炸♥时，它失去了大部分质量
When one of them blows up, it loses most of its mass.
同时也失去很多引力
It loses a lot of its gravity.
它没有足够的引力
It doesn't have enough gravity
来拉住小质量恒星
to hold on to the lower-mass star.
所以当它们在旋转时，其中一个爆♥炸♥了
So they're spinning around, this one blows up,
突然，另一个发现
and suddenly, this one finds itself
自己从星系中被弹射了出去，这就解释了一切
slingshot out into the galaxy, and that explains everything.
它从大质量恒星中得到碳元素
It got the carbon from the high-mass star.
大质量恒星爆♥炸♥了，小质量恒星就以非常高的速度
The high-mass star blew up and flung that lower-mass star out
被甩了出去
at very high velocity.
那么我们的星球被一个会飞的
So what are the chances of our planet
吸血鬼恒星烧毁的几率有多大呢？
getting fried by a flying vampire star?
在浩瀚的银河系中
In the vastness of the galaxy,
我们的太阳系是个幸运的小目标
our solar system presents a mercifully tiny target.
任意两颗恒星靠得足够近
It is so rare for any two stars
以至于发生这种情况都是非常罕见的
to get close enough together for this to happen,
即使是在一颗恒星能够存在的数十亿年时间里
even over the billions of years that a star can live,
这种情况几乎不可能发生
that it's almost never going to happen
在任何一颗恒星的一生中发生
in the lifetime of any given star.
会飞的吸血鬼不太可能摧毁地球
Flying vampires may be unlikely to destroy the earth,
但有另一种类型的杀手恒星
but there's another type of killer star out there
却存在一个明确而现实的危险
that offers a clear and present danger,
我们知道它可能会袭击我们，因为它以前就做过
and we know it could hit us because it's done it before.
2008年3月
March 2008.
天空中亮起一束微弱的闪光，不到一分钟就消失了
Stargazers watched open-mouthed as a faint light in the sky
天文学家观察到这个后，惊讶地张大了嘴巴
blinked into life and less than a minute later faded away.
这对天文爱好者来说是一场罕见的盛宴
A rare treat for the stargazers, but a stark reminder
但它也提醒我们，我们的星球
that our planet is in the firing line
正处于宇宙中最强大的杀手恒星——一种被称为
from the most powerful type of killer star in the universe,
伽玛射线暴的宇宙超级武器——的枪口上
a cosmic superweapon known as a gamma ray burst.
布洛克: 伽玛射线暴
Bullock: Gamma ray bursts.
这些宇宙射线枪
These cosmic ray guns are the most powerful,
是宇宙中最强大
the most deadly weapon
最致命的武器
that the universe has come up with.
伽玛射线暴发的喷流
The jets of the gamma ray burst
实际上不会持续很长时间
actually don't last very long.
几分钟后就会消失
They go off in really just a couple of minutes.
但在这段时间里，释放的能量
But in that time, the energy released
相当于1000亿年内
is equivalent to a hundred trillion nuclear weapons
每秒发射一百万亿个核武器
going off every second for a hundred billion years.
伽玛射线暴是一种
Gamma ray bursts are super-concentrated beams
超集中的高能光束，其冲击力
of high-energy light, and they pack enough punch
足以将附近的行星变成蒸汽
to reduce nearby planets to vapor.
他们一种超新星
They're a kind of supernova,
但它更像是一个超级超新星
but it's more like a super supernova,
一般情况下，超新星爆♥炸♥会摧毁一颗恒星
the idea being that instead of blowing up a star
并把碎片向各个方向扩张
and letting the debris expand in every direction,
然而不知何故
what if somehow,
这个爆♥炸♥并没有向各个方向扩张
instead of blowing up in every direction,
而是把能量吹向一个方向
it blew up in one direction,
以某种方式聚集了所有的材料
that it was somehow focusing all of that material
并像光束一样
and it was being shot out like a beam
从爆♥炸♥中心射出
from the explosion center.
布洛克: 这里的关键点是
Bullock: The key insight here
我们讨论的东西
is that we're not talking about something
并没有像球体一样爆♥炸♥
that's exploding like a sphere
并向四面八方扩散能量
and spreading its energy out in all directions.
伽玛射线暴以光束传播，所以它会把所有的能量
A gamma ray burst is beamed, so it's taking all of its energy
全都指向我们
but pointing it right at us
并直接向我们射击
and firing it directly towards us.
这就是它如此强大的原因
That's why it's so powerful.
2008年的伽玛射线暴直接击中了地球
The 2008 gamma ray burst landed a direct hit on the earth,
但它是来自遥远的地方
but it had come from so far away,
这一超级武器似乎失去了威力
this superweapon appeared to have lost its punch.
天文学家们很快计算出了光束的来源
Astronomers quickly calculated where the beam had come from,
并确定了宇宙远端的一个位置
and they pinpointed a location on the far side of the universe.
令人难以置信的是
Incredibly, this cosmic sniper's bullet
这颗宇宙狙击手的子弹已经在太空中穿行了70亿年
had been traveling through space for seven billion years,
远比我们太阳系的年龄还要长
far longer than the age of our solar system.
我们说的是一种有能量巨大的东西
We're talking about something that was so energetic that
甚至你用肉眼来观察它
had you been looking at it with your naked eye,
你也能看到它，即使它离我们有
you could see it, even though it was more than
70亿光年之遥
seven billion light years away.
你能想象一个如此充满能量
Can you imagine something that energetic,
如此猛烈的东西，然而在天空中只是以一颗
something that violent appearing as a gentle little star
温柔的小星星的形式出现吗？
going on and off in the sky?
想象一下
Think about that for a second.
这是一个非常明亮的东西
You've got this thing that's so bright
你可以用肉眼看到它
that you could see it by naked eye,
即使它在可观测宇宙的一半
even though it's halfway across the observable universe.
2008年，我们很幸运
In 2008, we got lucky.
如果同样的伽玛射线暴
If the same gamma ray burst had gone off
在几千光年内爆发
within a few thousand light years,
地球的大气层就会变成等离子体
the earth's atmosphere would have been turned to plasma.
但我们现在是安全的，对吧？
But we're safe now, right?
这样事情每天都在宇宙的某个地方
These things are happening somewhere in the universe
发生着，好吧？每一天
every day, okay? Every day.
我没有说错
I am not misspeaking here.
不是每一年，不是每一个世纪
Not every year, not every century,
也不是每一个千年
not every millennium.
每天，在宇宙的某个地方
Every day, somewhere in the universe,
在组成我们宇宙的
in the hundreds of billions of galaxies
数千亿个星系中，都有一颗超大质量的恒星
making up our cosmos, there is a supermassive star
在制♥造♥这些喷流，并把它周围
that is creating these jets and frying everything
几百光年内的一切都炸得粉碎
within a few hundred light years of itself.
那么这些融化行星的气流从何而来
So where do these planet-melting jets come from,
我们又该有多担心呢？
and how worried should we be?
汤普森: 所以你首先要有一颗快速旋转的
Thompson: So what you do is you take a massive star
大质量恒星
that's rapidly rotating.
一颗快速旋转的大质量恒星
A massive star that's rapidly rotating burns through
当燃烧掉所有的核燃料
all of its nuclear fuel and eventually produces
最终在其中心产生一个铁核
an iron core at its center.