了解宇宙是如何运行的（2010）

How the Universe Works S11E05

Part 15 April 10, 2023, 10:20 a.m.

因此，当火星内核冷却时
And so as Mars's core cooled,
内核中的对流速度会减慢
the convection in that core
would have slowed down, to
直到不会产生磁场
the point where no magnetic
field would be generated.
直到不会产生磁场
the point where no magnetic
field would be generated.
一旦火星上的磁场被关闭
Once the magnetic field
at Mars is shut off,
那么，对大气层的保护就结束了
well, that's the end of the
protection for the atmosphere.
37亿年前
ROWE:
3.7 billion years ago,
太阳攻击着毫无防备的火星
the Sun attacks
the defenseless Mars.
随着时间的推移太阳风会猛烈地
The solar wind just
bombards it and strips it
轰击它并迅速地将其大气中从星球上剥离
away of the atmosphere
very quickly over time.
没有了热的“毛毯”
ROWE:
Without its thermal blanket,
火星表面结冰
Mars's surface freezes,
and the atmospheric
大气压力骤降
pressure plummets.
大气压力骤降
pressure plummets.
随着大气压力的下降
As the atmospheric pressure
drops, surface water
地表水逐渐蒸发甚至蒸发掉
gradually evaporates
or even boils away.
金星也遭受了气候灾难
ROWE: Venus also suffered
a climate catastrophe.
我们在它的表面找到了线索
We find clues on its surface.
像太阳系中所有行星大小的天体一样
Like all planetary-sized
bodies in the solar system,
金星上也存在有
Venus has impact craters on it
金星上也存在有
Venus has impact craters on it
小行星撞击造成的撞击坑
from asteroids
smacking into it,
但没有那么多，这有点奇怪
but there aren't that many,
which is a little odd.
它们并不像
ROWE:
They're not damaged
我们在其他星球上看到的陨石坑那样受损
like the craters we see
on other worlds.
兰扎:它们看起来是崭新的，好像还没有改变过什么
LANZA: They look pristine,
as if nothing has modified them,
就像昨天发生的一样
as if they happened yesterday.
所以这表明这些陨石坑
So that suggests
these craters and the surface
和它们所在的表面都非常年轻
on which they reside
are both very young.
有几种理论认为，大约5亿年前
ROWE: There are several
theories suggesting that
火山爆发
volcanic eruptions
使地壳重新出现在星球表面
resurfaced the planet around
500 million years ago.
使地壳重新出现在星球表面
resurfaced the planet around
500 million years ago.
有一种观点认为，金星的地壳非常厚
One idea is that Venus has
a very thick crust,
它不像地球那样有板块在移♥动♥
and it doesn't move around in
plates like Earth's does.
所以它只是覆盖在星球上的一个盖子
So it's just a lid over
the planet, and eventually,
最终，压力越来越大，越来越大
the pressure builds up
and builds up
直到它——砰，一下子释放出来
and builds up until it --
boom, lets out all at once.
拉德博:一场灾难性的事件
RADEBAUGH: A catastrophic event
that overturned
它掀翻了金星的整个地壳，并重新浮出表面
the entire crust of Venus
and resurfaced it.
另一种理论认为
ROWE:
An alternate theory suggests
这种重新浮出表面的过程持续了数百万年
the resurfacing happened over
millions of years.
拉德博:一系列的大型火山爆发
RADEBAUGH: A series of large
volcanic eruptions
会使地壳完全重新浮出表面
that would have completely
resurfaced the planet.
想象一下在金星上所看到的事件——我的意思是
Imagine watching
this event on Venus -- I mean,
整个地壳的翻转？
the overturn of
an entire crust?
这真是太令人敬畏了
That's just completely
awe-inspiring.
火山活动释放出大量气体
ROWE: Volcanic events
release huge amounts of gas.
冰岛的埃亚菲亚德拉火山
Icelandic volcano,
Eyjafjallajokull,
每天喷发出30万吨♥二氧化碳
blasts out up to 300,000 tons
of carbon dioxide every day.
金星的火山活动可能已经爆表了
Venus's planet-wide volcanism
would have been off the charts.
如此大规模的全球性火山活动
Such a huge worldwide bout of
volcanic activity would release
会在金星大气中释放大量的大量二氧化碳
huge amounts of carbon dioxide
in the Venusian atmosphere.
科学家认为这种巨大的气体释放
ROWE: Scientists think
this enormous release of gas
科学家认为这种巨大的气体释放
ROWE: Scientists think
this enormous release of gas
可能引发了金星的气候变化
may have triggered
the Venusian climate change.
二氧化碳在金星大气中积聚
Carbon dioxide
built up in Venus's
吸收了来自太阳的热量
atmosphere, trapping
heat from the Sun.
达特内尔:一旦金星上的气候开始变暖一点
DARTNELL: As soon as the climate
on Venus started to warm up
海洋的蒸发量就会增加
a little,
there's greater evaporation
而大气中的水蒸气
coming off the oceans,
and that water vapor
本身就是温室气体
in the atmosphere
is itself a greenhouse gas.
气候变得更加温暖
The climate gets even warmer.
金星的温度为华氏880度（约470摄氏度）
ROWE: Venus reaches
880 degrees Fahrenheit.
任何生存的机会都在燃烧
Any chance
for life broils away.
然而地球也面临着一个炙热的未来
The Earth also faces
a searing hot future
当教父，太阳，开始膨胀
when the aging Godfather,
就会再次攻击他的家人
the Sun, bloats up and attacks
his family once again,
变成一个致命的大规模杀伤性武器
transforming into a lethal
weapon of mass destruction.
变成一个致命的大规模杀伤性武器
transforming into a lethal
weapon of mass destruction.
在过去的40亿年里，我们的暴徒家族
ROWE: For the last four billion
years, our mob family,
太阳系，和谐地生活着
the solar system,
lived in harmony,
但没有什么是永恒的
but nothing lasts forever.
教父，太阳
The godfather, the Sun,
会变老，变胖，变刻薄
will grow old, fat, and mean.
像太阳这样的恒星，它的氢
Stars like the Sun
only have enough
只能够让太阳维持融合大约100亿年
hydrogen to fuse for about
10 billion years.
这意味着在大约50亿年后
So that means that
in about five billion years,
这意味着在大约50亿年后
So that means that
in about five billion years,
太阳的氢将会耗尽
the Sun will actually
run out of hydrogen.
没有氢燃料，聚变就会停止
ROWE: With no hydrogen
fuel left, fusion stops.
核心崩溃并重新点燃，开始聚变氦
The core collapses
and reignites, fusing helium.
南斯:所有这些聚变释放的能量
NANCE: The energy released by
all of this fusion causes
导致恒星向外膨胀，成为一颗红巨星
the star to balloon outwards
and become a red giant.
导致恒星向外膨胀，成为一颗红巨星
the star to balloon outwards
and become a red giant.
红巨星就像一个愤怒的老流氓
ROWE: The red giant is like
a bitter old gangster.
它膨胀而好斗，攻击内行星
Bloated and aggressive,
it attacks the inner planets.
当太阳变成红巨星时
Mercury and Venus
are gonna be engulfed
水星和金星将被太阳吞没
by the Sun as it becomes
a red giant.
它会烧毁两颗行星
It burns up both planets.
接下来就是地球
Next in line, Earth.
然后宇宙扔给我们一条救命稻草
Then the universe