与摩根·弗里曼一起穿越虫洞（2010）

Through The Wormhole With Morgan Freeman S02E09

Part 2 April 19, 2021, 2:37 p.m.

运动的最小公分母
the lowest common denominator of locomotion.
鲎这样的东西
Things like horseshoe crabs
爬上海滩产卵
were crawling out on the beach and laying their eggs
此时翼龙则在天上飞翔
when pterodactyls were flying in the sky.
我们与这些动物所分享的特征之一
One of the features that we share with these animals
就是杠杆式的骨架
is a lever-type skeleton.
我手上有杠杆
I have levers in my hands.
就是它让我做如此动作
That's what allows me to do that.
我有杠杆在我的肘部肩部
I have levers in my elbows, in my shoulders.
基本想法是
The basic idea is
利用具有较高机械优势的杠杆
to use a lever that has a high mechanical advantage,
把大量肌肉力量提供给
that delivers a lot of the muscle force
杠杆的外端
to the output side of the lever.
成功的布局
Successful designs
如将四肢与坚硬骨骼连接起来
like jointed limbs and hard skeletons
一次又一次表现在化石记录中
show up again and again in the fossil record.
我们今天看到它们就在我们身边
We see them all around us today,
迈克尔期盼在别的世界里也能看到它们
and Michael expects to see them on other worlds, too.
并不在乎骨骼是不是
And it doesn't matter whether the skeleton
我们骨骼那样的羟磷灰石所构成
is made out of hydroxyapatite like our bones,
还是这种动物的甲壳素所构成
made out of chitin like this animal,
或者是碳纳米管构成
or carbon nanotubes.
一旦规则容易到了足以让
When a principle is easy enough
自然选择成为了偶尔发现
for natural selection to stumble across,
那么就会一而再再而三地演化
then it will evolve over and over again.
在这个星球上独♥立♥演化
On this planet, it has evolved independently
在不同时期至少有了六次
at least half a dozen different times.
有充分理由相信
And there's every reason to believe
它们普遍适用于
they will be just as common
任何星球的任何生态系统
in any other ecosystem on any other planet.
连接肢体的躯干动作如杠杆
A torso with jointed limbs acting as levers.
这是对外星人的很恰当的基本解剖
It's a good basic anatomy of an alien,
但我们能否更进一步想象它们真实的形态呢？
but can we get closer to imagining their true form?
在19世纪
In the 19th century,
查尔斯·达尔文保留了一系列的笔记
Charles Darwin kept a series of notebooks
记载了动物的形状是如何进化成
chronicling how the shapes of animals had evolved
去适应它们所处的环境
to adapt to the environments they lived in.
其它星球上的生命之书会是啥样子的呢？
What would a book of life on other planets look like?
解剖适应可能在异域环境中的发展
What mind-bending, anatomical adaptations
究竟有何匪夷所思之处呢？
might develop in alien surroundings?
环境塑造生物依赖它们的生态
The environment shapes creatures depending on their ecology.
大气的密度
Density of the atmosphere,
不管你是否有覆盖全球的海洋
whether or not you have a world-covering ocean,
都将在历史上形成巨大的差异
is gonna make a big difference in the history
从而构成了生物体的形状
and, thus, in the shape of the organisms.
这就是为什么
Which is why
要了解外星人的模样
to know what aliens look like,
我们就必须更多地了解它们生存的星球
we must learn more about the planets they live on.
一直到最近
Until very recently,
我们都没有其它行星存在的证据
we had no proof other planets existed,
更别说它们的地貌及大气层
let alone any idea what their landscapes or atmospheres
会是何种模样
might be like.
然而现在作为人类史上首次
But now, for the first time in human history,
我们能够看到远在我们太阳系以外的世界了
we can see worlds far outside our solar system.
现在我们知道了外星人可能居住的地方
And now that we know where E.T.s could live,
我们越发接近揭露它们隐匿的面孔了
we're getting closer to revealing their hidden faces.
我们若想知道外星人的模样
If we want to know what aliens look like,
我们首先得知道它们居住之地的一些情况
we first have to know something about the places they live.
直到最近这是不可能的
Until recently, this was impossible.
我们的望远镜只能观看恒星
Our telescopes could only see stars,
看不到其周围的行星
not the planets that orbit them.
如今外星人猎手已有了专门的研究飞船
Today, alien hunters have a dedicated research ship
漂浮在距离地球2000万英里的地方
floating 20 million miles from Earth,
它发现的新世界数以千计
and it's discovering new worlds by the thousand.
3...2...
点火
Engines start.
起飞
Zero.
德尔塔Ⅱ载着开普勒升空了
And liftoff of the Delta II rocket with Kepler.
2009年
In 2009,
航♥天♥局发射了其最新型太空望远镜
NASA launched its latest space telescope --
开普勒
Kepler.
其目的不是为了拍照
It's designed not to take pictures,
而是侦测遥远恒星亮度上
but to detect the tiniest changes
细微的变化
in the brightness of distant stars.
其目标是银河系我们所在的旋臂上的一片区域
Its target area is a patch of our arm of the Milky Way
从我们这里一直延伸出去有3千光年远
stretching out 3,000 light-years away from us.
哈佛大学教授迪米塔·萨瑟罗夫
Harvard professor Dimitar Sasselov
是开普勒首席科学家之一
is one of Kepler's lead scientists.
用开普勒望远镜
The beauty of how the Kepler telescope
探索小如地球的行星的
discovers planets as small as the earth
方法
is the method,
我们称其为凌日法
which we call the transit method.
这很容易理解
It's very easy to understand.
就是行星在其轨道上
So, the planet is passing on its orbit
在恒星的面前经过
in front of the star.
它的阴影造成星光有一点点昏暗
Its shadow causes that light to dip just a little bit,
这样一来我们就知道有行星的存在了
and that's how we know there is a planet there.
到开普勒完成其使命时
By the time Kepler is done with its mission,
迪米塔预计它将会发现
Dimitar expects it will have found
约100颗地球大小的行星
around 100 planets the size of Earth.
然而它所寻找的大量的行星
But the vast majority of the planets it is finding
几乎与我们的世界毫无共同之处
have almost nothing in common with our world.
开普勒已经有了一八宝箱的怪异行星
Kepler already has a treasure chest
如果你愿意的话
of weird planets, if you will --
非常有趣的各种各样的行星
very interesting, diverse planets.
我们有开普勒-10号♥星它坚如钢铁
So, we have Kepler-10, which is as hard as iron.
接着我们有两三颗行星
Then we have two or three planets
在六颗行星组成的开普勒-11星系里
in the Kepler-11 system of six.
其中的一两颗是水行星
One or two of them are water planets --
一片汪♥洋♥
endless ocean.
接下来我们的行星
Then we have planets
几乎是浓密的大充气球或发泡塑料
almost the density of a beach ball or styrofoam.
或许最有趣的开普勒发现
Perhaps the most intriguing of Kepler's discoveries
是约300倍的超大尺寸版本的地球
are around 300 super-sized versions of Earth --
岩石构成的行星但要重上5倍
planets made of rock, but up to five times as heavy.
要说有人能想象其景色
If anyone can imagine the landscapes
外星人会在那里慢跑游泳骑行
where aliens might jog, swim, or glide,
那就是戴安娜·瓦伦西亚
it's Diana Valencia.
业余三项全能运动员
Part-time triathlete,
她是首批剖析这些超级地球的
she's one of the first geologists
地质学家之一
to break ground on these super earths.
我没有锤子
I do not have a hammer.
我不破碎石头
I do not break up rocks.
我所做的是建立数学模型
What I do is I do numerical models
来了解地球的运作
to understand how the Earth works
并用它来了解
and use that to understand
更大或更小的行星是如何运作的
how bigger earths and similar planets work, as well.
为了了解
To understand
超级地球是否能够存在生命
whether the super earths could harbor life,
戴安娜瞄准推动岩石行星的
Diana is zeroing in on the basic geological engine
基本地质引擎
that powers rocky planets --
板块构造
plate tectonics.
行星坚硬外壳运动的
The movement of a planet's hard outer crust
推手是其底下
is driven by a hot and viscous layer
高温粘稠的半融化岩石
of semi-molten rock below it
其活动宛如一罐冒泡的蜂蜜
moving much like a jar of bubbling honey.
这个实验向我们表现了大致的情况
This experiment here shows us in broad lines what happens.
地幔是一种非常粘稠的液体
The mantle is a very viscous fluid,
两种液体对温度都很敏感
and both fluids are very sensitive to temperature.
我们打开这个来加热模拟地球的引擎
So, as we turn this heat up to simulate Earth's engine,
你就会看到在其表面以下的活动