了解宇宙是如何运行的（2010）

How the Universe Works S11E05

Part 4 April 10, 2023, 10:20 a.m.

because of
electrostatic forces,
相互粘附
because of
electrostatic forces,
基本上是静电粘附
basically static cling,
这几乎与你房♥间里的尘埃团
and it's almost exactly
identical to how
形成方式完全相同
a dust bunny forms
in your room.
萨特:这些是宇宙尘埃团，总有一天
SUTTER: These are cosmic dust
bunnies that
会成长为巨大的行星
will some day grow up
into giant planets.
天文学家称这些宇宙尘埃团为鹅卵石
ROWE: Astronomers call these
cosmic dust bunnies pebbles.
我们认为聚集的尘埃颗粒形成了
We think clumping dust
particles formed trillions
数万亿个直径约一英寸的鹅卵石
of pebbles each around
an inch in diameter.
这是行星构造的第一步
It's the first step in
planet construction.
这是行星构造的第一步
It's the first step in
planet construction.
形成行星的下一步
The next step in
forming a planet
涉及到星子，这些物体的大小
involves planetesimals
and these are objects that are
大约在半英里到100英里之间
roughly half a mile
to 100 miles in size.
但鹅卵石是如何形成星子的
ROWE: But how pebbles build
planetesimals was
一直是个谜，因为鹅卵石不能很好地结合在一起
a mystery, because pebbles
don't play well together.
原行星物质的颗粒
Grains of protoplanetary
material stick
是由于静电荷而粘在一起
together because
of static charge.
问题是，一旦它们变得太大
The problem is,
once they get too big,
力就不够了，它们就会
that force isn't enough,
and they'll just
互相排斥
bounce off each other.
然而，我们知道，必须一直到达
Yet we know that we have to
get all the way up to hundreds
数百英里宽的尺寸才能构建的星子
of miles across to build
our planetesimals.
当你试图把聚集在一起的粒子
How do you build a bigger
structure when the particles
相互碰撞时
that you're trying
to lump together
如何建立一个更大的结构呢？
are bouncing off of
each other?
沃尔什:因此，一个新的想法出现了
WALSH: So a new idea
came forward about how to make
关于如何实现从鹅卵石大小的物体
this big jump from
pebble-sized things
到星子的巨大飞跃
all the way up to
planetesimals,
这依赖于在恒星周围的气体中
and this relies on
the interaction of a huge number
大量鹅卵石一起移♥动♥的
of pebbles moving together
through the gas
大量鹅卵石一起移♥动♥的
of pebbles moving together
through the gas
相互作用
around the star.
巴蒂金:在围绕年轻太阳的
BATYGIN: In the disk
of gas and dust that encircles
气体和尘埃盘中
the young sun,
鹅卵石会开始合并成这些大的云
pebbles will begin to coalesce
into these big clouds,
就像个体的鱼会形成
much in the same way that
individual fish will form
鱼群一样
schools of fish.
越来越多的鹅卵石加入了云
ROWE: More and more pebbles
join the cloud.
最终，足够多的鹅卵石聚集在一起
Eventually,
you get enough of them
它们在自身引力下坍缩
together that they collapse
under their own gravity
形成一个大的星子
and make one big
planetesimal.
形成一个大的星子
and make one big
planetesimal.
星子要成长为行星
ROWE: The planetesimals
face a race
就要和时间赛跑
against time to grow
into planets.
他们必须从原行星盘中
They must grab enough
building material
获取足够的建筑材料
from the protoplanetary disk
before their Don,
否则太阳就会把它们都炸飞
the Sun,
blasts it all away.
46亿年前，一场激烈的战斗
ROWE:
4.6 billion years ago,
在家族的首领太阳和他的
a fierce battle erupts between
the head of the family,
不断成长的孩子们行星之间爆发了
the Sun, and his children,
the growing planets.
教父全副武装，充满危险
The Godfather is armed and
dangerous and threatening to
威胁要用他的武器——太阳风
destroy the planet's
food source
摧毁行星的食物来源
with his weapon of choice,
the solar wind.
有一股强烈的高能粒子风
There's this strong wind
of high-energy particles
有一股强烈的高能粒子风
There's this strong wind
of high-energy particles
来自太阳
coming out of the Sun.
能够吹散气体盘
That blows away the disk
of gas.
行星们必须在太阳把气体云赶走之前
ROWE: The planets must fight
to grab hold of
争夺剩余的资源
the remaining resources before
the Sun drives them away.
所以这是一场与时间的赛跑——
So it's a race against time --
Jupiter is racing
木星正在与太阳赛跑，在太阳把气体云全部吹走之前
the Sun to capture
as much material as
尽可能多地捕获物质
it can before the Sun
blows it all away.
我们通过研究其他太阳系
And what we see from studying
other solar systems is
看到这些圆盘只能持续大约500万年
that those disks only last for
about five million years.
看到这些圆盘只能持续大约500万年
that those disks only last for
about five million years.
我们曾经认为太阳系的原行星盘
ROWE: We used to think
of the solar system's
就像黑帮家族来吃饭的
protoplanetary disk
like an old-school diner
老派餐厅
where the mob family
came to eat.
第一个孩子，木星，先通过吞食星子而成长
The firstborn child, Jupiter,
grows by wolfing down
接着就是吞食气体
planetesimals, followed by
a second course of gas.
霍普金斯:行星形成的旧模型是这样的
HOPKINS: The old model of planet
formation is the idea that
这些直径几英里的大星子
these large-ish planetesimals
that are miles across
碰撞并相互粘在一起
collide and stick to
each other,
有点像粘土模型，直到形成一个
kind of like modeling clay,
until you get a bigger
越来越大的物体
and bigger object that can
最终它变得非常巨大
eventually get so massive that
it starts to then pull in
最终它变得非常巨大
eventually get so massive that
it starts to then pull in
它开始拉进周围更分散的气体，形成气态大气
the more diffuse gas around it
to form a gaseous atmosphere.
这是一个简单的想法，但有一个大问题——
ROWE: It's a simple idea,
but with a big problem --
时间
time.
根据旧的模型
By that old model,
it would take upwards of
需要1亿年的时间才能积累足够多的星子
100 million years to accumulate
enough planetesimals to do that.
在太阳把所有气体吹走之前
ROWE: Way too long
for Jupiter to grow
木星没有那么多时间生长
before the Sun blows all
the gas away.
2017年，当朱诺号♥宇宙飞船
We found
a clue to how Jupiter
调查木星的核心时
beat the problem of
the disappearing gas
调查木星的核心时
beat the problem of
the disappearing gas
我们发现了木星是如何解决
in 2017, when the Juno