了解宇宙是如何运行的（2010）

How the Universe Works S05E04

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

来容纳液相物质
for that liquid phase of matter.
所以即使是像氮这样的东西
So even for something like nitrogen,
你不仅要提高温度
you not only have to just turn up the temperature
让氮变得温暖
and get nitrogen warmer,
还要有一定的大气压力
there also has to be some atmospheric pressure,
需要更厚的大气
a thicker atmosphere is needed
来维持表面的液氮
to maintain liquid nitrogen on the surface.
科学家推断，在过去的一百万年里
Scientists deduce that in the last million years,
冥王星一定变暖和了
pluto must have warmed,
使冰川蒸发
evaporating glaciers
并使大气充满了氮
and filling the atmosphere with nitrogen.
但是什么导致了如此极端的气候变化呢?
But what could've caused such an extreme climate shift?
科学家们首先观察冥王星那细长的围绕太阳运行的轨道
Scientists first look to pluto's elongated orbit around the sun.
每隔248地球年
Once every 248 earth years,
冥王星的椭圆轨道就会使它接近太阳
pluto's elliptical orbit brings it close to the sun.
但这短暂的升温
But this brief warming
并不足以使冥王星的大气层变厚
isn't sufficient to thicken pluto's atmosphere.
当它靠近太阳时
When it comes in close to the sun,
它就会走得越来越快
it goes faster and faster.
当它远离太阳时
And as it moves away from the sun,
速度会慢得多
it goes much slower.
所以在冥王星上，夏天不会
So on pluto, summer doesn't last anywhere
像冬天那么长
near as long as winter.
但由于这颗矮行星
But from time to time,
不稳定的倾斜，所以一半冥王星
one half of pluto gets a super summer
会时不时会迎来一个超级夏天
thanks to the dwarf planet's unstable tilt.
我们从冥王星的北极和南极
We know from the way pluto's north
随着时间的推移而摆动的
and south pole wobble over time
方式中，我们知道代表冥王星
that that top that represents the spinning sphere
旋转球体的顶部并不像地球一样稳定
of pluto is not nearly as stable as the earth.
嗯，我们的地球在23.5度左右倾斜
Um, our planet is tipped over at about 23 1/2 degrees
你知道，在那里……
and sits that way for, you know, for ...
几千年一次
for millennia at a time.
然而，冥王星就不那么稳定了
Pluto, on the other hand, is much less stable.
它的两极随时间漂移
And its poles wander over time.
每一百万年左右
Once every million years or so,
冥王星就会完全向一侧倾斜
pluto tips completely on its side,
在它近距离经过太阳时
exposing the northern hemisphere
将北半球暴露在
to constant sunlight
持续的阳光下
during its close pass of the sun.
轨道移♥动♥产生的热量改变了
And the warmth from this orbital shift transforms
行星的表面
the surface of the planet.
想象一下冥王星变温暖
Picture pluto as it warms,
大气层变厚，充满了云层
the atmosphere thickens and fills with clouds,
暖风扫过平原，冥王星的冰川
a warm wind sweeps across the plains
开始融化
and pluto's glaciers begin to melt.
像动物从冬眠中苏醒一样
Like an animal emerging from hibernation,
冥王星苏醒了
pluto comes to life.
就好像
It's almost as if
在过去以及未来的时间中
it's undergoing these periodic changes
冥王星一直在经历着
where it's warmer and colder and warmer
变暖和变冷的
and colder in the past
周期性的不断变化中
and maybe again in the future.
冥王星表面会有液体吗？
Will pluto have liquid on its surface, even ...
即使只是暂时的？
even if only temporarily?
这意味着什么？那会是什么样子呢？
What would that mean? What would that even look like?
80万年后
800,000 years from now,
冥王星将再次苏醒
pluto will awake once again.
它将完全倾斜面向太阳
It will tilt over completely to face the sun
它的山脉将充满
and its mountains will fill
氮气流动的声音
with the sound of running nitrogen.
这样你就能看到氮的流动
WoYou begin to actually see flowing rivers of nitrogen.
你可以站在氮湖的岸边
You could stand on the shore of a nitrogen lake.
会有带着有机分子的
There'd be pink snow
粉色雪落在你身上
with organic molecules coming down on you.
这真是一个神奇的世界
What a truly magical world.
“新视野号♥”的遗产
The legacy of new horizons
远远不止是冥王星
goes far beyond just pluto.
它改变了我们看待银河系中
It changes the way we view frozen worlds
冰冻世界的方式
across our galaxy
以及这些遥远世界提供的各种可能性
and the possibilities these far-off worlds offer.
它告诉我们，在银河系中存在着
It tells us that there's this huge stage
一个巨大的生命舞台
for the play of life out there in the galaxy,
嗯，一个各种各样的世界
um, a huge variety of worlds.
你想象的某个世界，它可能就存在于某个地方
You image a world, it probably exists out there someplace.
这就是冥王星给我们的启示
That's kind of the lesson that pluto has for us.
它……它告诉我们……外面的事情
It ... it tells us that ... that things can be
比你想象的
a lot more interesting out there
更要精彩得多
than you can possibly imagine.
冥王星真的启发了我
Pluto has really inspired me.
这让我知道我们可能会错到什么地步
It's shown me just how wrong we can be.
我们以为我们已经知道冥王星是什么了
We thought we understood what pluto would be
结果却完全不同
and it was entirely different.
作为一名科学家，你会想
And as a scientist, you gotta think,
我们还有多少东西要去发现？
how much more out there do we have to discover?
至少冥王星教会了我们这一点
If nothing else, pluto taught us that.