了解宇宙是如何运行的（2010）

How the Universe Works S08E01

Part 16 Jan. 30, 2022, 2:57 p.m.

被拉到月球的表面
and pulled down
to the lunar surface.
我们现在知道，从小行星撞击中喷射到太空的物质
We now know the material ejected
into space from asteroid impacts
也可以到达其他行星
can travel to other planets,
as well,
这就解释了我们在地球上发现的
which would explain
the 100 mars meteorites
100颗火星陨石
we've found here on earth.
我们认为可能有大量的物质
We think that there was probably
the exchange of a huge amount
在不同的天体之间交换
of material
between different bodies,
地球到月球，再回来到火星
earth to the moon
and back again and to mars.
在我们的太阳系中，每次撞击
With each impact that occurs
in our solar system
都会喷射出各种各样的物质，这些物质
that ejects all types of
material that allows material
可以在行星之间、行星与卫星之间，以及卫星与卫星之间交换
to swap from planet to planet,
moon to planet, moon to moon.
所以这些物质最终
And so there's all
of this material
会从一个地方传播到另一个地方
that eventually travels
from place to place.
如果另一颗巨大的小行星撞击地球
Narrator: Should another giant
asteroid hit our planet,
这种行星间的交换可能会给地球上的生命
this planetary interchange
may give life on earth
提供一条生命线
a lifeline.
兰扎:如果你今天思考这样的影响
Lanza: If you think about
such an impact today,
你知道吗，有很大的机率，很多生命
you know, the chances are high
that a lot of life would be
可能是所有人类生命都将被毁灭
wiped out, much of life,
probably all of human life.
一颗足够大的小行星撞击地球
It's certainly possible that
a big enough asteroid strike
完全毁灭这颗行星，这当然是有可能的
could completely sterilize
the planet.
没有任何生命
Talking about
no life whatsoever.
恕我直言，如果有一颗
Not to put too fine
a point on it,
能杀死恐龙的小行星
but if there's a dinosaur killer
asteroid out there
撞上地球，那么作为一个物种
and it hits the earth,
the chance of humanity's
人类生存的机会，嗯，不是很大
survival of such a thing
as a species, mm, not great.
人类可能无法生存
Narrator:
Humans may not survive.
但一些科学家认为，简单的生命形式可以
But some scientists believe
that simple life forms could.
♪
♪
小行星过去曾多次
narrator: Asteroids have hit
our planet many times
撞击地球
in the past.
一次巨大的撞击毁灭了地球上70%的生命
One giant strike wiped out
70% of all life on earth.
如果另一颗巨大的小行星撞击我们，生命还能存活吗？
If another huge asteroid
hits us, can life survive?
♪
萨特:如果一块巨石击中了地球
sutter: If a giant rock hits
the earth and kills almost
杀死了地球上几乎所有的生命，那还有一线希望
all life on earth,
there is a slim line of hope.
这是因为地球上的泥土、岩石中
And that's because the dirt,
the rocks on earth
充满了细菌，微生物
are infused with bacterial life,
with microscopic life.
在一次巨大的撞击中
And in the event
of a giant impact,
这些岩石中的一些会被喷射到太空中
some of these bits of rock
will be ejected into space
可能会四处漂浮
and might float around.
在小行星撞击后，任何喷射到太空中的物质
After an asteroid impact,
whatever ejected
都可能含有微生物
into the atmosphere
could contain microbial life
当它落在行星表面上时，这些微生物
that when it falls back down
on to the ground
可能会在该行星上重新播种生命
could re-seed the life
on that planet.
♪
一些细菌可以在太空的恶劣条件下生存
narrator: Some bacteria can
survive the harsh conditions
可以应对小行星撞击，重返地球
of space and can cope with
an asteroid strike, reentry,
并重新返回地球表面
and landing back
on earth's surface.
♪
我认为就地球上的生命而言
I think in terms of life
on planet earth,
我们已经知道我们生活在一个适应性很强的星球上
I think we've learned that we
live on a very resilient planet.
我认为某种形式的生命，即使它必须
And I think life in some form,
even if it has to crawl
从细菌阶段重新进化
its way back
from bacterial stage,
我认为这个星球上的生命将会勉强生存
I think life on this planet is
going to going to eke through.
普雷特:生命很擅长寻找生存之道
Plait: Life is pretty good at
figuring out a way of surviving.
我们知道，地球上的生命
We know that life
first formed on the earth
早在40亿年前就开始形成了
well over 4 billion years ago
而且在这段时间里从未被消灭过
and has never been wiped out
in all of that time.
每次大灭绝之后
There's always been something
总会有一些东西
after every major
mass extinction.
所以生命还会继续只是不一定是我们
So life will continue.
It just won't necessarily be us.
小行星撞击另一个星球
Narrator: An asteroid strike
on another world
可能是地球上生命最初起源的原因
may be how life on earth
started in the first place.
布洛克:有个有趣的想法，那就是
Bullock: There's an interesting
idea that an asteroid strike
小行星撞击另一颗行星可能会在地球上孕育生命
on another planet could have
actually seeded life on earth.
这个过程是这样的，有一个生命
And the way this works is,
you have a life
以某种方式在其他星球上站稳了脚跟，比如火星
that's somehow gotten a foothold
on some other planet like mars,
一颗巨大的小行星撞击了那个星球
a big asteroid strike hits
that planet
撞掉了它的一部分，最终那部分落在地球上
and knocks a piece of it off,
eventually rains down on earth,
带来了生命
carrying with it life.
我们可能将地球上生命的存在归功于小行星的撞击
We may owe the existence of life
here to asteroid impacts.
这只是推测，但这是一种很酷的想法
That's speculative,
but it's kind of a cool thought.
播种生命的小行星可能曾经撞击过我们
Narrator: Life seeding asteroids
may have hit us in the past,
将来也会有其他小行星撞击我们
and other asteroids
will hit us in the future.
其中一个可能是阿波菲斯
One of those maybe apophis,
在不到半个世纪的时间里到达
arriving in less than
half a century.
也许我们会改变它的方向
Maybe we'll deflect it.
也许它会独自想念我们所有人
Maybe it'll miss us
all on its own.
不管怎样，我们都得密切关注
Either way, we need
to keep tabs on it.
塞勒:这是我们作为一个物种能做的最好的事情，这很有趣
Thaller: The best thing we can
do as a species, and it's funny
因为这听起来几乎像是我在为天文学家
because it almost sounds
like I'm advocating
争取更多的工作
for more jobs for astronomers.
我们需要继续观察天空
We need to keep looking
at the sky.
我们需要用更灵敏的仪器，更长、更深入地
We need look at the sky
longer and deeper,
观察天空，更多地
with more sensitive instruments
了解我们周围的情况
and get more of a sense
of what out there is around us.
这是我们人类最终生存所需要做的
That's what our species needs
to do to ultimately survive.
因为现在我们有能力
Because now we have
the ability
更好地看待这些事情
to see these things
a little bit better,
我们有能力更好地保护自己
we have the ability
to protect ourselves better.
不一定要是个惊喜
It doesn't have
to be a surprise.
你知道，我们第一次看到巨大的撞击不一定是因为
You know, the first time we see