了解宇宙是如何运行的（2010）

How the Universe Works S01E02

Part 5 April 18, 2021, 7:55 p.m.

wider than our solar system
高速穿越星系
and shoots clear through the galaxy.
这个超大质量黑洞点燃一个类星体
The supermassive black
hole has ignited a quasar.
类星体是宇宙中最亮的物体
Quasars are literally the
brightest objects in the universe.
它们亮度很高
They're so intense
令整个星系黯然失色
they can outshine an entire galaxy.
这是M87星系一个真实类星体照片
This is a real photograph of a
real quasar in the galaxy M87,
距离我们5000万光年
50 million light years away.
类星体从所在星系喷出大量气体
Quasars blast away huge quantities
of gas from the surrounding galaxy,
每分钟喷出总量相当于10个地球
the equivalent of 10
Earths every minute.
气体受热膨胀向外扩散
When you heat up a gas, it tends
to expand and it blows outward.
有些像风但规模巨大
And it's sort of like a
wind but on a huge scale,
于是产生黑洞风
and you get a black hole wind,
即是从黑洞喷出的气体
gas blowing out from the black hole.
黑洞吸入气体, 类星体将气体喷出
Black holes suck gas
in. Quasars blow it out.
但最终, 没有多余气体来制♥造♥恒星
But eventually, there's
no gas left to make stars
星系也就停止了成长
and the galaxy stops growing.
因此我们认为星系最终的规模
So we think that the eventual
size that a galaxy can achieve
取决于其中心的黑洞
depends on the black hole in its centre.
二者休戚相关
The two are tied together.
失去了气体原料
With no gas left to feed on,
类星体逐渐萎缩并消失了
the quasar jets shrink and die.
星系中心只剩下一个超大质量黑洞
What's left is a supermassive black
hole at the centre of the galaxy
和许多年轻恒星
with a whole lot of young stars,
银河系年轻时就是这样
just like our Milky Way
back when it was young.
在银河系早期, 当它是年轻星系时
Early on in the history of the Milky
Way, when it was a young galaxy,
可能是个类星体
we were probably a quasar.
大概每个星系早期都曾经是类星体
Probably every big galaxy was
a quasar when it was young,
但现在银河系已经成年
but right now, we're old enough
整个星系安静下来
that the galaxy has quieted down.
现在天文学家正在寻找类星体
Now, astronomers are
looking for quasars,
这有可能是我们找到更多黑洞
the secret to finding more black holes,
和弄清其运作方式的重要线索
and figuring out how they work.
钱德拉天文台是一台太空望远镜
The Chandra Observatory
is a space telescope
能探测到类星体发出的X射线
that can detect the powerful
X-rays quasars send out.
它已找到数千个类星体
It's found thousands.
这些影像展现出各种形状类星体
These remarkable images show
quasars of all shapes and sizes
向太空喷发射线
firing out into space.
每个类星体都是年轻星系的雏形
Each one is a signpost
for a young galaxy
它们中心都存在一个新生黑洞
with a new black hole at its centre.
这些类星体最终会安静下来
These quasars will eventually calm down
当年轻星系逐渐成熟和成形
as their galaxy matures
and takes its final shape.
我认为宇宙很像人类
I guess the universe
is a lot like people,
年轻时充满活力
active when they're young,
长大后变得比较安静和放松
little bit quieter and more
relaxed when they get older.
我们现在知道超大质量黑洞
We now know that
supermassive black holes,
和它们创造的类星体
and the quasars they create,
控制着星系
control galaxies.
黑洞对于理解星系的形成极为重要
Black holes are central to
understanding how galaxies form.
它们是了解星系进化史的关键
They're a key to understanding
how they evolve with time.
因此, 更明确地说它们是…
So, in fact, rather than being
obscura, they're fundamental
认识星系和宇宙的基石
to our understanding of our
galaxies and our universe.
进一步了解黑洞的唯一办法
The only way to find out
more about black holes
就是加以仔细观察
is to get a good look at one.
但近距离拜访似乎不是好主意
And since an up-close visit
is. well, not a good idea,
天文学家试图采取新方法
astronomers are trying to
devise a way to take a picture
拍摄银河系中心的超大质量黑洞
of the supermassive black hole
at the heart of our own galaxy.
因此需要像地球一样大的望远镜
To get it, they'll need a
telescope as large as Earth itself.
银河系中心存在一个超大质量黑洞
There's a supermassive black hole
at the centre of the Milky Way.
藏身于围绕银河系中心旋转星团中
It's hidden by a dense cluster of
stars circling the heart of the galaxy.
我们希望在不久将来能够见到它
But soon, we hope
we'll be able to see it
眼见为实
Seeing is believing.
那会很棒, 若能到达那里亲眼见到
It would be spectacular if we
can go right up there nose-to-nose
银河系中心的黑洞的事件穹界
with the event horizon of the black hole
at the centre of the Milky Way galaxy.
这就是我们的圣杯
And that's the Holy Grail.
多数星系中心都隐藏着一个…
A supermassive black hole lies hidden
超大质量黑洞
at the centre of most galaxies.
我们知道它们存在
We only know they're there
因为绕着其转动的恒星
because the stars around them
速度高达每小时数百万哩
are drawn in at millions
of miles per hour.
但我们还是有可能对黑洞边缘
But there might still be
a way to take a picture
也就是事件穹界, 进行拍照
of the very edge of the
black hole, the event horizon.
多勒曼的研究团队
Shep Doeleman and his team
正致力捕捉显示它的外形的影像
are trying to capture an
image that shows its outline.
我们其实是在旋转气体云中
We're essentially looking for the shadow,
or the silhouette of the black hole
寻找黑洞的轮廓
within this cloud of gas
that's swirling around it
我们对这个技术寄予厚望
This technique that we're
exploiting is the best hope,
希望勾勒出宇宙这个…
I think, we have to actually
image a region of the universe
我们一直看不见的区域
which has hither to have been
completely invisible to us.
光学望远镜不能直接观测到黑洞
Optical telescopes can't
see the black hole directly,
但黑洞周围的发光炽热气体
but the glowing superheated
gas surrounding the black hole
会发射出无线电波
sends out radiowaves
我们可以利用电波来勾勒一个影像
that can be used to make an image.
大型无线电望远镜能够接收到
Huge radio telescopes
这些来自太空的信♥号♥♥
pick up these signals from space.
天线调整方位角和高度
The antenna will move
in azimuth and elevation.
位于波士顿附近麻省理工学院的…
This one, at the MIT
observatory near Boston,
天文望远镜超过100呎宽
is more than a hundred feet wide.
探测到从25000光年之外发射的
It's big enough to detect
very faint radio emissions
非常微弱的无线电辐射
from the black hole in our
galaxy, 25,000 light years away,
但这架望远镜规模太小无法成像
but it's not nearly big
enough to capture an image.
我们需要多个类似的望远镜
We need to take multiple
copies of these telescopes,
将它们放置在世界各地
place them around the world
以形成与地球等大的虚拟望远镜
to create a virtual telescope
as large as the Earth itself.
从夏威夷到智利, 再到非洲
Doeleman's team will link up
radio telescopes around the globe,
他们将全球无线电望远镜连接起来
from Hawaii to Chile to Africa.
当整个网络连接好后
When the whole network is connected,
他们有一个直径1万哩的虚拟天线
they'll have a virtual dish
over 10,000 miles across
观测能力是单个望远镜的500倍
with 500 times the power
of a single telescope.
虚拟望远镜足够强大
They think it will be powerful enough
可以拍摄到银河系中心的黑洞…
to take a picture of the event
horizon of the supermassive black hole