了解宇宙是如何运行的（2010）

How the Universe Works S08E08

Part 5 Jan. 30, 2022, 2:59 p.m.

We think we're getting
a bird's-eye view of it.
我们在向下看
And looking down the barrel,
我们看到的是吸积盘，基本上是正面的
we're looking at the accretion
disk basically face-on.
这意味着任何被黑洞炸飞的物质
That means that any material
that gets blasted away
都有可能正对着我们
from the black hole
could be aimed right at us.
我们应该担心耀斑到达地球吗？
Narrator: Should we be worried
about the flares reaching earth?
普莱特:这听起来令人担忧，这团气体
Plait: It sounds worrisome,
this blob of gas
释放出了巨大的耀斑
emitting these
huge flares of light,
但你必须意识到，这是26000光年远的地方
but you've got to realize,
this is 26,000 light-years away.
这是一段很长的路
That is a long way.
只有在地球上最大的望远镜上
It took an extremely sensitive
detector
安装了一个非常灵敏的探测器
on one of the largest
telescopes on earth
才能看到这些
to be able to see this at all.
地球现在是安全的
Narrator:
Earth is safe for now,
但我们对银河系中心了解得越多
but the more we learn
about the galaxy center,
它就变得越可怕
the more terrifying it becomes.
我们知道人马座a星
We know of sagittarius a-star,
是银河系中♥央♥超大质量黑洞
the central supermassive
black hole,
但现在我们开始怀疑
but now we're beginning
to suspect
它可能不是唯一的
that it might not be alone.
一群危险的黑洞
Narrator:
A dangerous swarm of black holes
可能正绕着银河系中心奔跑
could be racing around
the center of the milky way.
还有数千个可能躲在了视线之外
Thousands more may
be hiding from sight.
♪
超大质量黑洞人马座a星
narrator: The supermassive black
hole, sagittarius a-star,
主导着银河系的中心
dominates the center
of the milky way...
……影响恒星形成……
...Affecting star formation...
……在太空中雕刻出巨大的气泡
...And carving out vast
gas bubbles in space.
但是人马座a星可能不是这个星系上唯一的黑洞
But sagittarius a-star might not
be the only black hole in town,
甚至不是最危险的
or even the most dangerous.
泰勒:很久以前，我们就知道
Thaller:
We've known for a long time
在我们星系的中心
that there's a supermassive
black hole
有一个超大质量的黑洞
in the very heart
of our galaxy,
但可能有一群愤怒的小黑洞
but there may be an angry swarm
of smaller black holes,
在它周围嗡嗡作响
buzzing all around it.
2018年4月
Narrator: In April of 2018,
哥伦比亚大学领导的
astronomers led
by columbia university
天文学家公布了在银河系中心
revealed the results
of a hunting mission
进行的一次狩猎任务的结果
in the center of the galaxy.
他们利用钱德拉天文台12年的数据
They'd used 12 years
of chandra observatory data
来寻找恒星质量的黑洞
to seek out
stellar mass black holes.
即恒星死亡后，超新星爆♥炸♥
Black holes that are made
from the death of stars,
形成的黑洞
from supernova explosions,
被称为恒星质量黑洞
are called stellar
mass black holes.
♪
它们是由质量为
and these are made from stars
太阳很多倍的恒星组成的
that were many times
the mass of the sun.
寻找恒星质量的黑洞是很困难的
Narrator: Finding stellar mass
black holes is tough.
光无法逃脱黑洞的引力
Light can't escape
a black hole's gravity,
所以我们无法直接看到它们
so we can't see them directly.
恒星质量的黑洞只有几十英里宽
And stellar mass black holes
are only tens of miles wide,
几乎不可能被探测到
making them almost impossible
to detect.
所以天文学家在寻找一种特殊类型的
So astronomers look
for a special type
恒星质量黑洞
of stellar mass black hole.
我们寻找恒星质量黑洞的方法之一是
One of the ways that we look
for stellar mass black holes,
它们通常是吞噬伴星的吸血鬼
is that they often are vampires
eating a companion star.
这些吸血鬼是一对双星的一部分
Narrator: These vampires are
part of a binary pair,
这是一个恒星质量的黑洞，与一颗活着的恒星一起运行
a stellar mass black hole
in orbit with a living star,
黑洞正在吞噬它的伴侣
the black hole feasting
on its partner.
特伦布雷:对于那颗恒星来说
Tremblay: That black hole
黑洞就像一个非常非常致命的寄生虫
is like a very, very deadly
parasite for that star.
它正在剥离恒星表面的质量
It is ripping mass
off the surface of that star,
而这些物质就像雨点一样落向黑洞
and that matter is raining down
toward the black hole itself.
萨特:这种物质会发光
Sutter:
And that material lights up,
所以这让我们能够寻找黑洞
so this allows us
to hunt for black holes,
不是通过直接拍摄黑洞的照片
not through taking pictures
of black holes directly,
而是通过看到这种物质走向毁灭
but through seeing the material
falling to its doom.
问题是
Narrator: The problem is,
遍布星系的气体和尘埃
gas and dust spread
throughout the galaxy
阻碍了可见光从双星对到达地球
stops visible light from
the binary pair reaching earth.
但这对双星会释放出
But the binary pair release
another type of light
另一种更容易穿过气体和尘埃的光——
that passes through the gas
and dust more easily --
X射线
x-rays.
明加雷利:这个系统本身发射X射线
Mingarelli: The system itself
is emitting x-rays,
所以它们被称为X射线双星
so they're called
x-ray binaries.
所以这些是有用的，因为X射线
So these are useful,
because the x-ray emission
发射非常强大
can be very powerful
可以在地球上观测到
and can be potentially seen
from the earth,
即使双星非常遥远
even though the binary
is very far away,
比如在银河系中心
say, at the galactic center.
在X射线双星系统中
Narrator: The glowing disks of
material in x-ray binary systems
发光的物质盘比人马座a星
are almost a million times
smaller than the accretion disk
周围的吸积盘小100万倍，太小了
surrounding sagittarius a-star,
too small
我们无法详细地看到物质在它们周围旋转
for us to see the material
swirling around them in detail.
所以，我们把X射线双星看作X射线的小孔
So, we see the x-ray binaries
as pinpricks of x-ray light.
天文学家在银河系中心
Astronomers detect
12 of these x-ray binaries
一个3光年宽的小空间中发现了
in a small 3-light-year-wide
patch of space
12个这样的X射线双星
at the galactic center.
这就意味着在我们星系的中心
And that means that there could
be a much larger collection
可能会有更多的相对较小的
of these relatively tiny stellar
mass black holes
恒星质量的黑洞
in the heart of our galaxy.
如果黑洞是像我们认为的那样形成的
If black holes form the way
we think they do,
那么很有可能有一大群黑洞
there very likely
may be swarms of black holes
在人马座a星周围奔跑
racing around
sagittarius a-star.
但X射线双星的威力足以让我们探测到
Narrator: But x-ray binaries
that are powerful enough for us
这是非常罕见的
to detect are incredibly rare.