了解宇宙是如何运行的（2010）

How the Universe Works S05E04

Part 2 April 18, 2021, 7:46 p.m.

拉德博: 形成这样形状的火山，你要知道
Radebaugh: The kind of eruptions that make this shape of volcano
必须要在很长的时间内……
are, you know, hundreds or thousands of ...
继续成百上千次的喷发
of individual eruptions over time.
那些……那些岩浆……
They ... they erupt out of ...
从裂缝流出，流过表面
of the fissure and flow out across the surface.
然后它们就会堆积在一起
And then they just pile up on top of each other
随着时间的推移持续流出
and continue to flow out
最终形成一个巨大的盾牌
building up a broad shield over time.
同样的事情也发生在冥王星上
The same thing has happened on pluto,
只是从冥王星喷发出来的熔岩
it's just the lava that's erupted from
并不是像这样的
pluto doesn't look anything like this.
这个……它没有深的颜色
It doesn't ... it's not dark in color.
它不是由玄武岩构成的
It's not made of basalt.
相反，它是由水冰构成的
Instead, it's made of water ice.
与地球不同的是，冥王星地壳表面的基岩上
Unlike earth, pluto has a surface of frozen nitrogen
是冰冻的氮
on top of a bedrock
而地幔是固态的水冰
and mantle of solid water ice.
一定有一部分水冰
Some of this water ice
在某原因下融化了
must be melting to form
于是形成了爆♥炸♥性的液体泥浆流
explosive flows of liquid slush
喷射到冥王星的表面
that spew out onto pluto's surface,
就像地球上炽热的岩石熔岩一样
just like hot rocky lava does on earth.
温暖的雪泥在地表迅速冻结
The warm slush freezes rapidly on the surface,
于是形成了广阔的冰盾
building up to form broad icy shields,
就像我们在地球和火星上发现的岩石盾
just like the rocky shields we find on earth and Mars.
如果地表下的水
If the water under the surface
可以被某种东西熔化，或某种能量
can be melted by something, some energy,
它就可以从地表喷发出来
it can burst through the surface
就像地球上的熔岩一样
and flow just like lava does here on earth.
所以并不是像这里这样的火山
So instead of volcanoes, like you have here,
而是冰♥火♥山，冷火山
you get cryovolcanoes, cold volcanoes,
就在这些更远的天体上
on these more distant objects.
我们对宇宙经常有一种短浅的看法
We have a myopic view of the universe thinking
认为一切都必须是这里的样子
everything has to be the way it is here.
然而在地球上，火山是热的
Here on earth, volcanoes are hot.
但在冥王星上，火山是冷的，而不是热的
But on pluto, volcanoes run cold, not hot.
也许关于冥王星的火山
But perhaps the most exciting thing
最令人兴奋的事情是
about pluto's volcanoes
它们几乎没有陨石坑
is that they're virtually free from impact craters,
这意味着形成冰♥火♥山的温暖的雪泥
meaning the warm slush that formed the ice volcanoes
一定是最近才流出来的
must have flowed out of them really recently.
这些特征非常非常的年轻
These features are very, very young.
冥王星今天还很活跃
Pluto is active today.
因为没有足够的时间
There hasn't been enough time
让彗星撞击冥王星
for the bombardments of comets impacting
并在轰击下形成一个历史印记
pluto to build up and build up a record cr...
呃，一个记录历史的陨石坑
uh, a record of craters on the surface.
所以冥王它还活跃着
Pluto is active today.
这是爆♥炸♥性标题
That's the headline.
冥王星上有活火山的可能性
The potential for active volcanoes
令科学家们感到震惊
on pluto stunned scientists.
然而当冥王星那张光滑心脏的特写图片
But they pale in comparison
展现出来时
when close-up images
活火山就显得苍白了
of pluto's smooth heart are revealed
因为这个德克萨斯大小的冰盆地
because this Texas-sized
似乎正在沸腾着
basin of ice appears to be boiling.
我们的太阳系到处都有遭受过暴♥力♥的伤痕
Our solar system bears the scars of a violent past.
撞击坑散落在岩石行星
Impact craters litter the surface of rocky planets
和行星的卫星表面
and moons like our own.
然而，在地球上，这些战争的伤疤
Yet, on earth, these battle scars
被熔岩，水和风给抹去了
are wiped away by lava, water and wind.
如果你现在看月亮，以及一千年后再看
If you look at the moon now and you look at it
两者的月亮不会有很大不同
in 1,000 years, not gonna be very different.
不过，如果你现在看一下地球
However, if you look at the earth now
等一个小时，你会发现天气
and wait an hour, right, we have weather,
火山
we have volcanoes,
以及湖泊都在来回移♥动♥
there are lakes that come and go.
海平面在成千上万年的时间里
The sea levels rise and fall over thousands
上下波动
and millions of years.
所以，呃，这些，呃，所有这些地质活动
So, uh, with, uh, all of this geologic activity,
都表明地球是一个有生命的世界
we say that the earth is a living world.
科学家们一直以为冥王星上有很多环形山
Scientists expected pluto to be heavily cratered,
就像我们的月球一样，是一个地质上死亡的世界
a geologically dead world similar to our moon.
但当2015年“新视野号♥”飞过时
But when new horizons flew past in 2015,
它发现了一片广阔的心形冰原
it revealed a vast, heart-shaped icy plain,
这片冰原看起来比其他行星上的年轻得多
which appears much younger than the rest of the planet.
而这片平原的西部
And the western part of this plain,
斯普特尼克平原，完全没有陨石坑
sputnik planum, was completely crater-free.
在我们看到的所有传回来的东西中
Of all the things that we saw coming back,
这个心脏，斯普特尼克平原
the heart, sputnik planum,
是最令人惊讶和最有趣的
was the most surprising and the most interesting
也是最能让人说出："哦，看那个"
and the most, sorta, "oh, look at that."
斯普特尼克平原宽阔而苍白的表面
The broad, pale surface of sputnik planum
为我们提供了一扇窗，让我们得以窥见
offers a window into pluto's unexpected activity
冥王星出人意料的活动，因为它看起来就像
because it looks just like the icy glaciers do,
地球上的冰川
here on earth.
表面上看不到任何陨石坑
There's not a crater to be seen anywhere across that surface.
这直接告诉我们它是年轻的
And that immediately tells us it's young.
有些估计可能是在1000万年以前
Some of the estimates are maybe as young as 10 million years,
你知道，就是因为有些东西
you know, only since that stuff
在四处游动并改变了地貌
has been moved around and changed.
这是……这是今天的地质术语
That's ... that's today in geologic terms.
一定有什么东西使表面
There's got to be something actively making
变得如此光滑
that surface for it to be that smooth.
有些东西会定期地
Something is regularly smoothing out
把斯普特尼克平原弄平
the surface of sputnik planum,
但是什么呢？
but what?
科学家们可以排除冰♥火♥山的可能性
Scientists can rule out cryovolcanoes.
它们会形成山脉，而不是平原
They make mountains, not plains.
那还可能是什么呢？
So what else could it be?
第一条线索来自于苍白的蛇纹线
The first clue comes from pale snaking lines
它们似乎延伸到了平原的北部边缘
that appear to feed into the northern rim of the plain.
这些蜿蜒的地貌看起来
These sinuous features look just like
就像地球上
the rivers of ice
山脉冰川形成的冰河
that flow from mountainous glaciers here on earth.
拉德博: 我们现在看到的是
Radebaugh: What we're looking at here is,
呃，一个巨大的冰川穿过山谷倾泻而出
uh, is a massive glacier pouring out across the valley
流入一个冰川湖
and emptying into a glacial lake.
我们首先注意到的是当我们看到……
One of the first things we noticed when we saw the ...
来自“新视野号♥”的特写图片
the close-up images from new horizons
不仅是一片广阔的平地冰川
is not only a vast field of kind of a flat glacier
而且是通往冰川的微小的补给网
but also tiny little feeder networks into the glacier,
就像山谷冰川，与这个冰川一样
like valley glaciers just like this one
流入更大的大♥陆♥冰川
emptying into the larger continental glacier.
冰一定是在冥王星的高地形成的
Ices must be forming in pluto's highlands
然后流入斯普特尼克平原
and flowing into sputnik planum,
就像地球上的高山上
just like outlet glaciers
流出的冰川一样
flow from high mountains here on earth.
但冥王星太冷了，水冰无法流动
But on pluto it's too cold for water ice to flow.
因此，供给斯普特尼克平原的源头
So the outlets feeding sputnik planum must be filled
必须填满一种非常不同的冰
with a very different kind of ice.
所以冰川必须是由氮这样的物质构成的
So the glaciers have to be made of things like nitrogen.
氮气是构成大气层的主要物质
Now, nitrogen is what makes up most of our atmosphere.
虽然这是气体
It's a gas here.
但在那个温度下，它会结冰
But at those temperatures it freezes and becomes an ice,
变成一个由氮组成的冰川
a glacier of nitrogen.
在冥王星上，氮冰有牙膏的质地。
On pluto, nitrogen ice has the texture of toothpaste.
它从由水冰组成的山上流下
And it flows down mountains made of water ice.
那些冰川在流动
Those glaciers are flowing.
更重要的是，它们上面没有陨石坑
And, what's more, there are no craters on them.