了解宇宙是如何运行的（2010）

How the Universe Works S05E07

Part 3 April 18, 2021, 7:47 p.m.

如果我们走到
If we walk to the edge of this
这堆蓝莓石的边缘
pile of blueberries,
我们可以看到
we could see the process by which
它们从岩石中侵蚀出来的过程
they're actually eroding out of the rock.
蓝莓石本来包裹在
The blueberries right here contain
这个石化砂岩层中
within this fossil sandstone layer.
风从这个方向吹来
The winds are blowing in this direction,
顺着地层往下吹
down the layers,
它们侵蚀了这里的软砂岩
and they're actually eroding out the soft sandstones right here
露出了非常致密的铁球
and leaving behind very dense iron nodules,
当它们从岩石中剥离出来后
and as they pluck themselves out of the rock,
就从山上滚下去，然后聚集在一起……
they roll down the hill and they collect...
就在这里，在地层之间
Right here, in between layers.
我们知道我们在火星上发现了类似的情况
We know we found conditions just like this on Mars.
我们在沙丘层石地表
We have fossil sand dune layers,
发现到处都是蓝莓石
we also have blueberries all over the surface,
所以我们知道火星上
so we know the same kinds of things
也发生过类似的事情
had to have happened on Mars that have happened here.
必须有水流穿过岩石
There has to be water flowing through the rock,
收集铁
gathering iron,
然后必须有大量的风
and then there has to be a huge amount of wind
剥离石化沙丘
to strip away the fossil sand dunes.
为了让蓝莓石能
For blueberries to exist
在今天的火星表面生存
on the surface of Mars today,
这颗红色星球在灾难性的撞击后
the red planet must have gotten its water
一定有了水和大气层
and its atmosphere back after the catastrophic impact.
由于火星表面有液态水
With liquid water on the surface,
生命的成分可能会再次结合
the ingredients of life might have combined, once again,
创造出第二代火星生命
to create a second generation of martians.
但是这些水是从哪里来的呢？
But where did this water come from?
答案令人惊讶
The answer is surprising.
它可能就在这颗行星上……
It could have been in the planet itself ...
而且水非常丰富
water is incredibly abundant.
我们知道在地球的
We know that there's water deep,
地幔深处有水
deep, deep in the earth's mantle,
所以完全有可能
and so it's entirely possible that on Mars
在火星深处存在水
there was water so deep in the planet
即使在灾难之后，现在它又回来了
that even after this catastrophe, it came back up.
在地球上
On the earth, scientists
科学家们通过传播地震的地震波
diffuse the seismic waves of earthquakes
以探测海底深处矿物质中
to detect an ocean's worth of water
化学成分所蕴含的海洋价值
chemically embedded in minerals deep underground.
类似的水源可能隐藏在
A similar water source could have been hidden
撞击后的火星表面下方数百英里处
hundreds of miles below post-impact Mars,
火山爆发可能会把水带回地表面
and volcanoes could have brought that water back to the surface.
将水从地表深处
One way for water to get from
输送到星球表面的一种方法
deep underneath the surface to the surface of the planet
是通过地质活动……
would be through geologic activities ...
比如,火山
volcanoes, for example.
我们知道火山会在地球上喷射出很多气体
We know that volcanoes spew out a lot of gasses on earth,
包括水蒸气
including water vapor,
我们也能在火星上看到火山
and we see volcanoes on Mars.
火星上有太阳系中
Mars is home to the largest
最大的火山
volcanoes in the solar system.
其中最大的是奥林匹斯山
The biggest of all, Olympus mons,
比珠穆朗玛峰高三倍多
is over three times taller than mount Everest.
44.9亿年前，火山喷发出带有水的熔岩
4.49 billion years ago volcanoes spew lava spiked with water
形成猛烈的暴雨
into the atmosphere and create ferocious rainstorms
淹没了火星表面
that flood the surface of Mars.
几万年后
Over tens of thousands of years
火星再次变成了一个水的世界
Mars becomes a watery world once again
为第二代火星生命的崛起
with the perfect conditions for a second generation
提供了完美的条件
of martians to rise up.
这样看来
It would seem that
当发生像火星那样的
when you have a massive collision,
大碰撞时生命在火星上
like what happened to Mars,
似乎就游戏结束了
it would be game over for life.
但还有更复杂的事情
But there's something more complicated going on.
也许那次小行星撞击
Maybe that asteroid impact kicked off
开启了火星上一个全新的生命周期
an entirely new cycle of life on Mars.
理论上说
In theory,
40亿年前
four billion years ago,
第二代单细胞细菌
a second generation of single-cell bacterial life
在火星上出现
arose on Mars,
并且太阳系的两颗行星上
and for the very first time there was life
首次出现了生命
on two planets in the solar system.
一亿四千万英里外，地球上的生命才刚刚开始
140 million miles away, life on earth had just begun,
多亏了地球上稳定的气候
and thanks to earth's stable climate,
生命终有一天会进化成我们
it would one day evolve into us.
但火星的情景却截然不同
But the outlook for Mars was very different.
来自火星勘测轨道飞行器的证据表明
Evidence from the Mars reconnaissance orbiter
一场冰冻的末日即将来临
suggests an icy apocalypse was about to strike.
对于第二代火星生命来说，凛冬将至
For Mars' second generation, winter was coming.
40亿年前
Four billion years ago,
地球上出现了第一个生命
the first life has arisen on earth,
但在火星上，生命可能开始了第二次
but on Mars, life may be starting out for a second time.
火星比地球更早有生命
It's possible that Mars
这是非常有可能的……只是它被摧毁了……
had life before earth did ... it got wiped out ...
然后通过给星球补水重新开始生命
and then got started again by rehydrating the planet.
一次行星碰撞
A planetary collision
将火星的大气、海洋都吹走了
has blown away Mars' atmosphere and oceans,
生命也随之消失
along with any life,
但巨大的火山将水从地底深处
but giant volcanoes have brought water back to the surface
带回了火星地表
from deep within the planet.
这可能会导致
This could have allowed
第二代生命的出现
for a second generation of life to rise up.
但这些火星生命将面临灾难性气候变化的
But these martians are about to be tested to their limits
极限考验
by catastrophic climate change.
2008年……美国宇航局的火星勘测轨道飞行器
2008 ... NASA's Mars reconnaissance orbiter
在火星表面高空飞行
flies high over the surface of Mars.
它的探地雷达仪器
Its ground-penetrating instruments
能探测地表深处
peer deep below the surface,
旨在解开火星的地质秘密
aiming to unlock Mars' geological secrets.
当它扫描火星赤道附近时
As it scans near Mars' equator,
轨道飞行器发现了一些不应该在那里的东西……
the orbiter spots something that has no right to be there ...
一个巨大的地下冰川
a vast, underground glacier.
一英里厚，三倍于洛杉矶的面♥积♥
One mile thick and three times the size of Los Angeles,
这种规模的冰只会在极寒的两极形成
ice on this scale should only form at the frigid poles.
唯一的解释是……
The only explanation ...
火星的赤道偏离太阳
Mars must have been tipped over
一定是被某个东西给掀翻了
with its equator tilted away from the sun.
随着时间的推移
The tilt on Mars' axis
火星轴线的倾斜度发生了显著的变化
has actually changed significantly over time,
它的移♥动♥是随机发生的
and in non-systematic ways,
这是一种非系统的方式
it just happens randomly that it will start moving,
因此有一些模拟实验表明
and so there are some models that suggest
整个火星几乎被完全掀翻了
that Mars has actually been almost tipped over on its end.
大多数行星都会摆动
Most planets wobble,
而且是不定时地，一旦摆动得非常厉害
and from time to time, they wobble so much
就会翻转，导致超级冬天的出现
they can tip over, leading to super winters.
如果这发生在地球上
If that had happened here on earth,
洛杉矶可能会变成北极
Los Angeles could become the arctic.
你可以想象火星上也发生了类似的事情
Well, you can imagine something similar would happen on Mars,
变化会非常的剧烈
how drastic the change would be.
你已经习惯了在头顶上看到太阳
You're used to seeing the sun overhead,
它非常温暖，阳光所到之处就可能有液态水
it's very warm, there's probably liquid water,
然而当行星开始向这个方向移♥动♥时
and as the planet starts going this way,
太阳就不会升到天空中那么高
the sun is not gonna rise as high in the sky.
最终，你可能要半年才能看到日出
Eventually you may not see sunrise for half a year,
那里的水也就会冻结成固体
and any water that's there is gonna be frozen solid.