了解宇宙是如何运行的（2010）

How the Universe Works S05E02

Part 4 April 18, 2021, 7:46 p.m.

between the largest kuiper belt object
在柯伊伯带中
that we know now
最大的天体的质量的数千倍
and the size of planet 9.
所以你说的是超级超级超级冥王星
So you're talking about super-mega-ultra-pluto.
它真的非常非常大
It's really, really big.
很难知道这样的冰球
And it's hard to know what an ice ball
会是什么样子
like that would look like.
推测仍然存在活动
It's not crazy to speculate that there could still be activity,
内部地质活动
internal geologic activity,
使这个世界免于寒冷和完全死亡
keeping this world from being cold
这并不疯狂
and totally dead.
在黑暗中窥视
Peering through the darkness
假想中的超级冥王星9号♥
to a hypothetical mega-pluto planet 9,
我们发现了一个巨大的冰世界
we discover a giant world of ice.
它的岩石比超级地球少得多
There's much less rock than a super-earth planet 9.
但仅仅是大量的冰就产生了足够的引力
But the mass of ice alone creates enough gravity
在核心深处产生热量，即使在这里
to generate warmth deep in the core, even out here.
维持一颗行星存活的真正核心是质量
The real currency of keeping a planet alive is mass.
它是否有足够的质量来保持内部的温暖?
Does it have enough mass to keep the interior warm?
质量是地球5到10倍的物体
Well, something that's 5 to 10 times
内部很可能是温暖的
the mass of the earth probably would be warm inside.
近距离观察，地表会发生喷发
Up close, the surface explodes with activity.
但这些火山喷出的是水冰，而不是熔岩
But these volcanoes spew water ice, not lava.
如果有一个巨大的冥王星存在
If something like a giant pluto exists,
我想这样的天体一定有
it must be the most amazing landscape
最令人惊叹的风景
to take a walk over.
你会看到这些冰♥火♥山喷出冰冻的水
You'd have these ice volcanoes spewing out jets
冰像雨点一样落在你身上
of frozen water, of ice raining down on you.
也许你会向外看
Maybe you'd look out over the landscape
看到数以百计的冰♥火♥山喷发
and see hundreds of these erupting.
这很有戏剧性，冰冷的景象
This dramatic, icy vista is a gateway
是通往一个秘密世界的大门
to a secret world,
一个巨大的，由液态水和冰晶混合而成的
a vast, slushy ocean of liquid water
泥泞海洋
mixed with ice crystals,
也许是太阳系中
perhaps the largest
最大的单一水体
single body of water in the solar system.
德达:也许会有足够的内热
Durda: There's gonna be enough internal heat, maybe,
把这里变成一个泥泞的水世界
to turn this into a slushy water world.
所以它不完全是类地岩质行星
So it's not quite a terrestrial, rocky planet.
它也不是天王星或海王星
And it's not a uranus or Neptune.
这是一个真正的海洋世界
It's a true mega-ocean world,
但也可能是一个非常寒冷的世界
but perhaps a very cold one.
9号♥行星是冰冻的冥王星吗？
Is planet 9 an icy mega-pluto?
问题在于规模
The problem is scale.
冥王星和柯伊伯带的其他天体都很小
Pluto and the other objects in the kuiper belt are tiny.
那么，相同的建筑材料
So how could the same building materials
是如何聚集在一起形成巨人的呢？
have come together to form a giant?
所以，认为第九大行星
So, the idea that planet 9
只是一个放大的冥王星的想法
is simply a really scaled-up pluto, a mega-pluto,
有一些困难
has some difficulties.
我们只是认为太阳系中
We just don't think that there was enough mass out there
不可能有足够的质量
in the far reaches of the solar system
聚集在一起来建造这么大的行星
to all come together to build a planet that large.
当你看柯伊伯带的时候
When you look at the kuiper belt,
你会发现这些小而冰冷的天体
there are all of these small, icy bodies.
那里没有什么很大的天休
There's nothing very big out there.
我们认为这不是巧合
And we think that's not a coincidence,
形成行星的尘埃和气体盘的物质
that the disk of dust and gas that formed the planets
靠近太阳会更多
had more stuff closer to the sun.
当你到达冥王星这里的的时候
And by the time you got out to where pluto is,
已经没有多少物质可以用来造行星了
there wasn't much material to build planets out of,
更不用说是一个
certainly not a planet
质量是地球5到10倍的行星了
5 to 10 times the mass of the earth.
那么，如果9号♥行星不是在冰冷的外部系统中形成的
So, if planet 9 didn't form in the icy outer system
也不是在多岩石的内太阳系中形成的
and didn't form in the rocky, inner solar system,
它是从哪里来的呢？
where did it come from?
更有可能的情况是
The more likely option,
9号♥行星形成于太阳系中部富含气体的区域
planet 9 formed in the gas-rich zone
木星、土星和海王星
in the middle of our solar system
也是在这个区域中形成的
that also created Jupiter, saturn, and Neptune.
一颗气态的9号♥行星可能与海王星♥相♥似
A gassy planet 9 could be similar to Neptune,
但可能更小一些
but perhaps a little smaller,
一颗迷你海王星
a mini-Neptune.
但它是如何比其他气态巨行星
But how would it get so much farther out
走得更远的呢？
than the other gas giants?
它会是什么样的呢？
And what would it look like?
想象一下，一个奇怪的、半透明的世界
Imagine a weird, translucent world
在黑暗中像一个巨大的深海生物一样发光
glowing in the dark like a giant deep-sea creature.
太阳系边缘的某些东西
Something on the fringes of our solar system
正在扰乱轨道并引起骚动
is upsetting orbits and causing a ruckus.
它会是一颗行星吗？
Could it be a planet?
让我难以置信的是
It's incredible to me that we now know
我们现在知道太空中
of thousands of other planets
有成千上万颗行星围绕着其他恒星运转
going around other stars in the sky,
但我们可能错过了
but we may have missed a big planet
太阳系中的一颗大行星
in our own solar system.
9号♥行星，除了它存在的可能性之外
Planet 9, a world we know almost nothing about,
我们对它几乎一无所知
beyond the possibility that it exists.
科学给出了有趣的猜想
Science suggests intriguing options ...
一个巨大的，岩石的世界，有着火的心脏
a giant, rocky world with a heart of fire,
或者一个充满巨大的
or an ice world filled
泥泞的海洋的冰的世界
with a giant, slushy ocean.
但每种理论的猜想都会带来新的问题
But problems with each theory have led to new hunches.
那么，如果它不是一个岩石多、金属多的超级地球
So, if it's not a rocky, metallic super-earth
也不是一个巨大的冰球或超级冥王星
and it's not a gigantic, ice-ball, mega-pluto,
那还剩下什么呢？
what's left?
答案是一颗气态巨星
And the answer is a gas giant.
我觉得这是最有可能的选择
And that strikes me as being the most likely prospect.
想想9号♥行星的质量和它现在的位置
When you think about the mass of planet 9
我的最佳猜测是
and where it is now, my best guess,
它有点像海王星的缩小版
it's something like a miniature version of Neptune.
这些气态巨行星
The gas giant planets
是我们太阳系的怪物
are the monsters of our solar system.
这些气态巨行星没有像地球那样的固体表面
Instead of a solid surface, like the earth,
而是有厚厚的、暴风雨般的大气层
the gas giants have thick, stormy atmospheres
向下延伸数万英里
that descend for tens of thousands of miles,
包裹着它们细小的岩石内核
shrouding their small, rocky cores.
木星是最大的气体巨星
Jupiter is the largest gas giant,
质量超过地球的300倍
over 300 times the mass of earth.
从木星开始
Moving out from Jupiter,
气态巨行星逐渐变小
the gas giants get progressively smaller,
土星，然后是天王星，最后是海王星
saturn, then uranus, and finally Neptune,
大约是地球质量的17倍
around 17 times the mass of the earth.
如果9号♥行星是一颗气态巨行星
If planet 9 is a gas giant,
它会更小
it'll be even smaller,
就像一个迷你海王星
a mini-Neptune.
如果第九大行星是小型海王星
If planet 9 is a mini-Neptune,
就会很像海王星
if it's a lot like Neptune,
那么它就不像地球那样
then it's not really like
是类地行星了
a terrestrial planet, like earth.
但它不像木星那样是一个巨大的气体行星
But it's not really like a gas giant, like Jupiter.
海王星是介于两者之间的奇怪天体
Neptune is this weird, in-between thing
它可能有一个岩石内核
where it's probably got a rocky core.
但实际上，大多数情况下，就是天文学家所说的冰
But it's actually, mostly, what astronomers call ices.
它里面有甲烷，水和其他各种物质
It's got methane in it and water and various other substances
在它上面有非常非常厚的大气层
and a very, very, very thick atmosphere on top of that.
海王星厚厚的云层
Neptune's thick clouds are stained blue
被甲烷分子染成了蓝色
with molecules of methane.
但9号♥行星的大气层可能是透明的
But planet 9's atmosphere could be transparent.
沃尔什:外面太冷了，你几乎无法
Walsh: It's so cold out there, you're getting almost
从太阳那里获得额外的能量