了解宇宙是如何运行的（2010）

How the Universe Works S05E04

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

温度攀升了……上升了8度
It has climbed ... climbed 8 degrees.
看看这个这是30
Look at this. It was 30.
突然间它就变成了38度（约3.3摄氏度），就在它结冰的几秒钟后
Now all of a sudden it's 38, just seconds after it froze.
这听起来可能有点违反直觉
It might seem kind of counterintuitive,
但结冰的水
but freezing water
实际上会向周围释放能量
actually gives off energy to its surroundings.
所有的动能，就是水分子
All of that kinetic energy, the motion of the water
在液体状态下的运动
molecules in the liquid state,
呃，现在这些
um, has to be given up
水分子由运动
for those water molecules
变成了固体晶体结构
to enter a solid crystalline structure.
释放出来的能量被称为融合的潜热
That released energy is called the latent heat of fusion.
当水结冰的时候，它会使周围的环境
It actually can warm the surroundings as water
变暖
is freezing into ice.
这就是科学家们认为地下海洋中的潜热
This is how scientists believe latent heat in an underground
可能导致冥王星上的冰♥火♥山活动的原因
ocean could be driving volcanism on pluto.
内部海洋的最上层在液态水
The upper most layers of the internal ocean freeze
和上面坚硬的冰相遇的地方结冰
where liquid water meets the hard frozen ice above.
冻结的过程中释放出潜热
This act of freezing releases latent heat,
潜热通过冥王星的地壳向上传播
which then travels up through pluto's crust,
于是推动了冥王星表面的地质活动
driving active geology on the surface.
拉德博: 我的意思是，这似乎只是一点点热
Radebaugh: I mean, this seems like just a little bit of heat
它是从……从这个冻结过程中产生的
that's forming from ... from this freezing process.
但如果有…一整层海洋都被冰壳冻住了
But if there's a ... a whole layer of ocean
这样就会产生巨大的热量
that's freezing up against the ice crust,
也许能激发出冰♥火♥山的
that's a tremendous amount of heat,
仅仅是由部分液态水海洋
maybe it could bring up cryovolcanoes driven
冻结产生的热量驱动的
simply by the heat from freezing in parts
这太神奇了
of the liquid water ocean, just amazing.
令人难以置信的是
Incredibly, just a few degrees
仅仅从冥王星的海洋中泄漏几度的热量
of heat leaking from pluto's ocean
可能就足以驱动冥王星的地壳表面
may be all it takes to drive the dynamic surface of pluto,
抬高山脉
to raise mountain ranges,
点燃含水的冰♥火♥山
to fire up watery volcanoes
并使含氮冰川从冰冷的山坡上
and to set nitrogen glaciers
急速下降
racing down icy slopes.
我们人类是有偏见的我们生活在这个温暖的星球上
We humans are prejudiced. We live on this warm planet.
如果你往地下几英里，那里的岩石…几乎是熔融
If you go down a few miles under the surface of the earth,
这是令人难以置信的热
the rock there is ... is almost molten.
所以我们认为
It's incredibly hot.
需要大量的能量
And so we think you need a huge amount of energy
来驱动火山
to drive volcanoes
间歇泉和板块构造等等
and geysers and plate tectonics and all that.
但事实并非如此
But that's not really the case.
只是岩石融化
It's just that rock takes
需要消耗很多能量
a lot of energy to melt and do all that.
而冰不需要那么多能量
Ice doesn't take nearly that much energy.
所以在冥王星上，如果有什么东西
So on pluto, if something was able to heat it up
能把它加热一点点，然后得到……
even a little bit and get that ...
融化后的水冰
that ... that water ice to melt,
就会产生和地球上相同的
that can drive the same sort of surface geology
地表地质现象
that we have here on earth.
如果我们的银河系充满了
And if our galaxy is filled with frozen worlds
像冥王星这样的
like pluto, the universe
冰冻世界，宇宙就会变得有趣得多
just got a whole lot more interesting.
所以银河系中的大多数世界都是……
And so it could be that most of the worlds in the ...
寒冷的世界
in the galaxy are ... are cold worlds.
可能银河系中大部分的火山活动
And it might be that most of the volcanism in the galaxy
实际上就是我们在冥王星上看到的
is actually the running cold volcanism
冷火山活动
that we see on pluto.
冥王星最终会改变我们
And pluto is actually going to end up changing the way
对任何固态行星的看法
we think of any sort of solid planet.
不知道为什么，它在不该活着的时候还活着
Somehow, it's still alive when it shouldn't be.
新视野号♥已经向我们表明
New horizons has shown us
冥王星很可能既有热量
that pluto most likely has both heat
又有液态水
and liquid water.
这个简单的事实
And that simple fact
提出了一种惊人的可能性:
raises an astonishing possibility:
距离太阳
Could tiny pluto,
30亿英里的微型冥王星
sitting 3 billion miles from the sun,
是否能成为生命的秘密避难所？
provide a secret haven for life?
在浩瀚的太空中
In all the vastness of space,
我们只知道一个星球是生命的家园
we only know of one planet that's home to life:
那就是我们的星球，地球
Our planet, the earth.
在地球上，我们拥有
On earth, we have all the ingredients
生命产生所需的所有材料
we needed for life to arise,
显然，我们就在这里
clearly, we're here.
但这三种物质基本上就是能量
But those three things are basically a source of energy,
液态水和有机分子……
liquid water, and organic molecules ...
即含碳分子
carbon-based molecules.
我们曾经认为地球是唯一
We used to think earth was the only world
拥有这三种元素的世界
with all three ingredients.
但当机器人探测器访问木星和土星时
But when robotic probes visited Jupiter and saturn,
他们发现了许多活跃的卫星
they found multiple active moons with underground
它们的地下海洋被热火山喷口加热
oceans warmed by hot volcanic vents.
而且这些世界似乎
And these worlds also appeared to be spiked
也含有生命的基本化学成分
with the basic chemical ingredients for life.
所以，如果木星的卫星木卫二
So if Jupiter's moon, europa,
和土星的卫星土卫二
and saturn's moon, Enceladus,
都被认为是潜在的生命避难所
are considered potential havens for life,
那为什么冥王星的地下海洋就不能呢？
why not the subterranean oceans of pluto too?
我们认为冥王星上可能有液态水
Well, we think there's liquid water possibly on pluto.
很明显，这里有一种能源
And there's clearly a source of energy.
它会有第三种成分吗？
Could it have that third ingredient?
如果是这样的话，想知道冥王星上
And, if so, is it that bizarre to wonder
是否会有生命存在是不是很奇怪？
if life could arise on pluto?
第三种成分是有机化学
The third ingredient is organic chemistry,
即构建生命机制的
the carbon-based molecules
碳基分子
that build the machinery of life.
令人惊讶的是，天文学家相信这些复杂的化学物质
Surprisingly, astronomers believe these complex chemicals
可以在寒冷的太空中自发形成
can form spontaneously in the cold of space.
你所需要的只是简单的碳基气体
All you need are simple carbon-based gases
和一种能量来源，通常是光
and a source of energy, usually light.
据我们所知，这种有机化学
The most active natural laboratory
最活跃的自然实验室
we know of for this kind of organic chemistry
是土星的巨大卫星土卫六的大气层
is the atmosphere of saturn's giant moon, titan.
当你观察土卫六时，你会发现它的大气层非常厚
When you look at titan, it has a very thick atmosphere,
比地球的还要厚
thicker than earth's.
它被雾霾包围着
And it's surrounded by this haze.
这种雾霾基本上是由有机分子构成的
And that haze is basically made of organic molecules
这些有机分子是由更基本的化合物产生的
that are created from the more basic compounds
这些化合物被紫外线照射后
that have been zapped by ultraviolet light
就会形成……
and built up to ...
来制♥造♥更复杂的有机化合物
to make these more complex organic compounds.
土卫六（泰坦）的大气层充满了简单的气体:
Titan's atmosphere is thick with simple gases:
甲烷、一氧化碳和氨
Methane, carbon monoxide, and ammonia.
当阳光照射到土卫六的云层顶部时
And when sunlight strikes titan's cloud tops,
这些气体结合在一起
these gases join together
形成复杂的有机分子
to form complex organic molecules,
悬浮在大气中
which hang in the atmosphere,
形成浓密的薄雾层
forming dense layers of haze.
科学家们称这些自然产生的有机分子为
Scientists call these naturally occurring organic molecules
“索林”
"tholins."
这是一个通用术语
It's a generic term, it's a blanket term
是对任何复杂的
for any sort of complex,
红色的有机分子的统称
reddish colored organic molecule
这些分子是由
that is formed from the splitting apart
更简单的
and reassembling of simpler,
呃，分子分♥裂♥和重组形成的
uh, starting, uh, molecules.
这些有机分子，这些索林
These organic molecules, these tholins,