了解宇宙是如何运行的（2010）

How the Universe Works S08E04

Part 1 Jan. 30, 2022, 2:58 p.m.

想象一个没有星星的宇宙——
narrator: Imagine a universe
with no stars --
一个黑暗、无尽的夜晚
a dark, endless night.
这不是科幻小说中的噩梦
This is not some
sci-fi nightmare.
这是我们的未来
This is our future.
在未来的某个时刻，当你抬头时
There will definitely be a point
in the future when, you look up,
你将再也看不到星星
you will no longer
be able to see stars.
泰勒:事情真的会变得越来越黑暗
Thaller: Things really will get
darker and darker,
直到几乎没有光的记忆留下
until there will be almost
no memory of light left.
数十亿年来，恒星给宇宙带来了生命
Narrator:
For billions of years, stars
brought life to the universe.
你之所以存在，就是因为有星星的存在
The fact that you exist at all
is because of stars.
现在，它们在恒星末日中灭绝了
Narrator: Now, they're dying out
in a star apocalypse.
斯特里克:影响可能是巨大的
Stricker: The effect
could be tremendous.
它可以渗透到整个宇宙
It can permeate
throughout the universe.
是什么导致了死亡
Narrator:
What's causing the die-off,
当灯熄灭的时候，生命会发生什么？
and what happens to life
when the lights go out?
最终，整个宇宙
Eventually, the whole
entire universe
开始变得有点奇怪
starts to get
a little bit weird.
宇宙是如何运行的
第八季第4集末日之星的死亡
在超过45亿年的时间里
narrator:
For over 4.5 billion years,
太阳用光沐浴着我们的地球
the sun has bathed
our home planet with light.
太阳明亮、稳定的光芒有助于生命的繁荣
Its bright, stable glow
helps life flourish,
但隐藏在夜空中的
but hidden in
the night sky,
其他行星系统就没有这么幸运了
other planetary systems
haven't been so lucky.
泰勒:每天晚上，我们都会
Thaller: Hanging right above
your head every night,
在你的头顶上看到星星的尸体
we see up there
these dead corpses of stars.
距地球400光年的地方有一个叫做 sdssj1228 的系统
Narrator:
400 light-years from earth
lies a system called sdssj1228.
一个由碎片组成的圆盘
A disk of debris orbits
绕着一颗死亡恒星的残余物微微发光
the faintly glowing leftovers
of a dead star.
J1228 是一颗死星
J1228 is a dead star.
这是一颗恒星的内核，它已经老化
It is a core of a star
that had aged,
外层被吹离了，露出了内核——
blown off its outer layers,
revealed the core --
它的大小与地球差不多
which is about
the size of the earth,
但其质量约为恒星的一半
but has about half
the mass of the star in it.
我们称之为“白矮星”
And we call these
"white dwarfs."
2018年5月
narrator: May, 2018.
天文学家使用世界上
Astronomers
investigated j1228
最大的光学望远镜——加纳利亚大望远镜
using the world's largest
optical telescope --
对j1228进行了研究
the gran telescopio canarias.
他们发现了围绕这颗白矮星
They discovered what appears
to be a ball of iron
运行的铁球
orbiting the white dwarf.
这块直径不到400英里（约6♥4♥4公里）的金属球
The lump of metal,
less than 400 miles across,
可能是一颗被摧毁的行星暴露在外的内核
could be the exposed core
of a destroyed planet.
这是这个系统过去的线索
It's a clue to
this system's past.
泰勒:当你看到一颗死亡恒星周围
Thaller: It's always
a little poignant
存在行星的证据时，总是会感到有点心酸
when you see evidence
of a planet around a dead star.
你懂的，想想那颗恒星还在闪耀的时候
You know, you think back of
when that star was shining,
那个恒星系里有生命吗？
and could there have been life
in that solar system?
j1228 系统是一个宇宙墓地
Narrator: The j1228 system
is a cosmic graveyard.
它可能看起来和我们的太阳系不同
It might look different
than our solar system,
但这是我们的未来
but this is our future.
发现一颗死气沉沉的行星围绕着一颗死气沉沉的恒星运转
This discovery of a dead planet
orbiting a dead star
就像在看一个水晶球
is like looking into
a crystal ball.
它是我们太阳系的未来吗？
And is it the future
of our own solar system?
是的
Yep.
想要看到你的未来，你知道吗
For a glimpse into your future,
you know,
你所要做的就是抬头看
all you need to do
is look up.
就像 j1228 一样，我们的太阳也会死亡
Narrator: Just like j1228,
our sun will die,
地球也会在这个过程中灭亡
killing off earth
in the process.
这种可怕的恒星末日的命运
This terrifying fate
will play out across the galaxy
将在整个银河系上演
in a star apocalypse.
我们的太阳是银河系中相当常见的一种恒星
Our sun is a fairly common type
of star in the milky way,
因此，银河系中的其他恒星
and so, other stars
in the milky way
也将经历与太阳相同的命运
will undergo the same sort
of fate as the sun.
它们最终会变成白矮星
They will end up
as white dwarfs.
因此，任何围绕类日恒星运行的行星
And so, any other planets out
there orbiting sun-like stars
都将经历类似的命运
will undergo
a similar fate.
一旦像太阳这样的恒星消失了
Once the stars like our sun
have died out,
会发生什么？
what's gonna happen?
生命还能在白矮星周围生存吗？
Could life still survive
around white dwarfs?
要想了解类日恒星的命运
Narrator: To understand the fate
of sun-like stars,
我们得看看它们的内部
we have to look
inside them.
埋在内部的是它们如何生存，以及为何死亡的线索
Buried within are clues to how
they live, and why they die.
普莱特:核心，就最中心的地方，那是恒星动力的来源
Plait:
The core, the very center,
that's where the action is.
这就是恒星将轻元素
That's where the star
is fusing light elements
融合成重元素的地方
into heavier elements.
这就像氢弹一样
And that works like
a hydrogen bomb.
是同样的东西
It's the same thing.
如果你把氢压缩到足够的程度，它就会变得非常热
If you compress hydrogen enough,
it gets very hot,
压力也会变得非常高
and the pressure
gets very high,
如果它聚变成氦，就会产生能量——即热量
and if fuses into helium,
and generates energy -- heat.
这就是每一颗恒星的核心所发生的事情
And that's what's happening
in the core of every star.
因为它们巨大的质量
Narrator:
Because of their enormous mass,
恒星拥有巨大的引力
stars have huge
amounts of gravity.
这种引力向内推，试图使恒星坍缩
This gravity pushes inwards,
trying to collapse the star,
但来自核心的聚变能量阻止了这种情况的发生
but fusion energy from the core
stops that from happening.
这是一种在重力向内推
It's really this sort of
very balanced dance
和聚变能向外推之间的非常平衡的舞蹈
between gravity pushing in,
fusion energy pushing out.
你可以把一颗恒星想象成
You can think of a star
as losing energy,
不断地向外界失去能量
continuously,
to the outside world
而引力在说，“是的，我要接管它”
and gravity is saying,
"yes, I'm gonna take over."
但是，不，恒星内部的核反应