了解宇宙是如何运行的（2010）

How the Universe Works S09E01

Part 4 March 16, 2022, 8:54 a.m.

that is bad news, because hot,
强大的风会扼杀恒星的诞生
powerful winds kill off
star birth.
风可以将正常形成恒星的气体推开
The winds can push away
the gas that would have normally
这样它们就可以
formed stars so they can
有效地熄灭星系中恒星的形成
effectively quench star
formation in a galaxy,
使其逐渐走向消亡
causing it to gradually die.
情况还会变得更糟
And it gets worse.
为了让一个星系产生恒星
In order for a galaxy
to produce stars,
它需要大量的气体和尘埃
it needs lots of gas and dust,
而这些气体和尘埃需要非常冷
and that gas and dust
needs to be incredibly cold.
来自黑洞的“热风”
Hot winds from
the black hole heat up
加热了气体云，所以它们不能坍缩成恒星
gas clouds so they can't
collapse into stars.
随着M87星的成长
As M87 star has grown,
它慢慢地停止了恒星的形成
it has slowly shut down
star formation.
随着星系中心黑洞不断地壮大
As the black hole in
the center of the galaxy grows,
它会产生越来越强的“风”
it has stronger
and stronger winds,
这意味着它会驱逐出越来越多的物质
and this means it's gonna
drive out more and more matter.
这就是它成为一个
And that's what makes it
a galaxy
无法再支持恒星形成的星系的原因
that can no longer support
star formation.
明加雷利:所以超大质量黑洞
MINGARELLI: So a supermassive
black hole can determine
可以决定星系中恒星的形成
the star formation happening
in the galaxy.
它可以帮助调节星系中气体的数量
It can help to regulate
the amount of gas in the galaxy
从而控制星系中形成恒星的
and therefore the number of
stars that are formed
数量
in a galaxy.
虽然M87星与它周围
Although M87 star is tiny
浩瀚星系相比很小
compared to
the vast galaxy around it,
但它仍然控制着它的宿主星系
it still controls its host.
当你把它和它所在的星系的大小
When you compare it to
the size of the galaxy
相比较时，就像拿一颗葡萄
it's sitting in,
it's like comparing
和地球的大小相比较
a grape to the size
of the Earth.
因此，与星系相比这么小的天体
So to think that something so
relatively small compared to
竟然能对整个宇宙的历史
the galaxy could have such
a profound effect over
产生如此深远的影响
effectively all of cosmic
history is
这就是黑洞能量的
just this remarkable
illustration of how energetic
绝佳例证
a black hole can be.
在超大质量黑洞
In the relationship between
与其周围物质之间的关系中
a supermassive black hole
and the material surrounding it,
黑洞起着主导作用
the black hole is in charge.
尽管M87星决定了一切，但它的过去
Although M87 star
calls the shots, its past,
现在和未来都不可避免地与其宿主星系
present, and future are
inextricably linked
联♥系♥在一起
to its host galaxy.
从我们的飞船上看到的是无尽的空间
The view from our ship is
endless space,
平静而不变
calm and unchanging.
但是M87星系有着狂暴的过去
But the M87 galaxy
has a violent past,
有自相残杀
a history of cannibalism,
死亡和毁灭的历史
death, and destruction.
我们已经穿越了M87星系
We've traveled
thousands of light-years
数千光年
across the M87 galaxy,
但它的超大质量黑洞
but its supermassive black hole
仍然很遥远
is still far in the distance.
从我们目前的位置来看
From our current position,
M87星可能看起来很小
M87 star may look small,
但它的质量是太阳的65亿倍
but it's 6.5 billion times
the mass of the sun.
那么它是怎么变得这么大的呢？
So how did it get so big?
我们仍在试图了解的一个
One of the big mysteries
that we're still trying to
大谜团
understand is what
是什么控制着星系中心的巨大黑洞的
controls how big the giant
black holes at the centers of
大小
galaxies become.
我们知道这
And we know that
it's tightly correlated
与星系的大小密切相关
with things like
how big the galaxy is.
越大的星系就有越大的黑洞
Bigger galaxies have bigger
black holes.
要了解M87星是如何变得如此之大的
To understand how M87 star
became so big, we have to
我们必须研究其星系的历史
investigate the history
of its galaxy.
我们需要发现M87星的宿主星系是如何变得
We need to discover
how M87 star's host galaxy
如此之大的
grew so large.
M87非常巨大
M87 is huge.
它是一个有着巨大黑洞的大星系
It's a big galaxy
with a big black hole.
特伦布雷:真的，真的很大
TREMBLAY:
It's really, really big.
这就是我们所说的最亮的椭圆星系
It's what we call
the brightest cluster galaxy,
这些所谓的最亮的椭圆星系
and these so-called brightest
cluster galaxies are among
是已知宇宙中最大的星系之一
the most massive galaxies in
the known universe.
通常认为，像M87类似质量的星系要小得多
Usually, a galaxy with the mass
of M87 is much smaller,
但M87却膨胀得很大为什么？
but M87 is puffed up
hugely. Why?
一个线索来自M87星系的布局
One lead comes from
the layout of M87's stars.
当我们在银河系中穿行时，我们看到
As we travel through
the galaxy, we see
恒星分布在一个比预期大100倍的
that the stars spread out
over an area 100 times larger
区域
than expected.
那么是什么使恒星分散的呢？
So what scattered the stars?
星系不是静止的，每个星系都在运动
Galaxies aren't static,
every galaxy is moving,
有时星系非常接近
and sometimes galaxies get
very close
会相互作用
and can interact
with each other.
“相互作用”是一种
Interact is a polite way
描述极端野蛮事物的婉转方式
of describing something
extremely brutal.
星系正在与其他星系碰撞
Galaxies are colliding with
other galaxies, they're
它们正在吞噬较小的星系，或者彼此撕裂
cannibalizing smaller galaxies
or tearing each other apart.
明加雷利:有时候他们就像赛车
MINGARELLI: Sometimes
they're like drive-bys,
他们会扭曲彼此的结构
and they'll warp
each other's structures.
有时星系会正面碰撞并合并
Sometimes the galaxies have
head-on collisions and merge.
合并会吸收新的气体和恒星
Merging pulls in
new gas and stars,
所以星系就会增长
so galaxies grow larger.
星系中同类相食的现象很常见
Galactic cannibalism is common.
也许M87星系吞噬了它的邻居
Maybe the M87 galaxy ate
its neighbors.
但是我们怎么知道的呢？
But how can we find out?
我们可以尝试识别
We could try to identify stars
来自被吞噬的星系的恒星
that came from
the consumed galaxies,
当然这并不简单
but that's not straightforward.
当你试图绘制出一个遥远星系的自己的恒星时
When you're trying to map out
a distant galaxy,
事实证明是一件非常困难的事情
it turns out using their stars
is a really hard thing to do.
它们与前景和背景混在一起