宇宙的奇迹（2011）

Why are we here?
我们为何在此
Where do we come from?
我们又来自何方
These are the most enduring of questions,
这些问题源远流长
and it's an essential part of human nature to want to find the answers.
而人类天性就爱探索答案
And we can trace our ancestry back
追根溯源
hundreds of thousands of years, to the dawn of humankind,
时间定格在几十万年前 人类文明出现之刻
but in reality, our story extends far further back in time.
实际上 我们的故事将延伸至更早的年代
Our story starts with the beginning of the universe.
从宇宙起源说起
It began 13.7 billion years ago.
宇宙起源于一百三十七亿年前
And today, it's filled with over 100 billion galaxies,
而今 宇宙中已形成逾千亿星系
each containing hundreds of billions of stars.
每个星系包含数千亿恒星
In this series, I want to tell that story because,
在这个系列里 我想向大家讲述这故事
ultimately, we are part of the universe.
因为说到底我们也是宇宙的一部分
So its story is our story.
宇宙的故事 便是我们的故事
The force at the heart of this story is gravity.
这个故事的主角便是引力
This fundamental force of nature built everything we see.
这最基本的自然力量建立了我们见到的一切
It creates shape and order,
它创造了形状和秩序
and it initiates patterns that repeat across the heavens.
它的鬼斧神工在宇宙中比比皆是
But gravity also forges
但引力也在宇宙中
some of the most alien worlds in the cosmos,
打造了另一些截然不同的世界
worlds that defy belief.
与信念相悖的世界
The quest to understand this fundamental force of nature
在探寻这基本自然力的真谛的途中
has unleashed a golden age of creativity, exploration and discovery.
促生了一个创新 探索 发现的黄金年代
And it's led to a far deeper understanding
这让对于身处宇宙中的我们
of our place in the universe.
对此有了更深远的理解
Every moment of our lives,
我们生命中的每一刻
we experience a force that we can't see or touch.
都在体验一种我们看不见摸不着的力量
Yet this force is able to keep us firmly rooted to the ground.
然而这种力量能使我们扎根与地面
It is, of course, gravity.
它 就是地心引力
But despite its intangible nature,
尽管它难以名状
we always know it's with us.
它却一直如影随形
If I was to ask you,
如果我问你
"How do you know that there's gravity around here?"
你怎么知道周围有地心引力
Then you might say, "Well, it's obvious."
你也许会说 这很明显啊
You know, I can just do an experiment, I can drop something.
我可以做个实验 扔点什么东西
Well, yes, but actually,
没错 但实际上
gravity is a little bit more subtle than that.
地心引力比这更令人难以琢磨
But to really experience it, to understand it,
但为了真正体验它 理解它
you have to do something pretty extreme.
你必须使出点绝招来
And this plane has been modified to help me do it.
为此 我们改装了这架飞机
Thanks to its flight plan, it's known as the Vomit Comet.
根据飞行计划 它被形象地称为喷发彗星
Once we've climbed to 15,000 metres,
攀升至一万五千米的高空之后
this plane does something no ordinary flight would do.
这架飞机将进行一些非比寻常的动作
Its engines are throttled back, and the jet falls to earth.
关小油门的喷气式飞机将直落向地面
And then, something quite amazing happens.
然后 神奇的事情发生了
Push to me, push to me!
推我一把 推我一把
I'm now plummeting towards the ground
我正垂直落向地面
just like someone's cut the cable in a lift,
就像有人切断了电梯里的缆绳
and you see that I'm not moving.
你瞧 我没有掉下去
Relative to Einstein, we're all just floating.
就像爱因斯坦说的 我们只是浮在空中
By simply falling at the same rate as the plane,
我们仅仅是同飞机以相同的速度下落
for a few fleeting moments, we are all free of gravity's grip.
便能在某些瞬间 逃离地心引力的掌心
But this isn't just a joyride.
但这可不仅仅是一番玩乐
There's something very profound here,
这里有些意义深远的东西
because although I'm falling towards the ground, as you can see,
因为尽管如你所见 我正落向地面
gravity has completely gone away.
地心引力已经完全消失了
Gravity is not here any more.
地心引力在这里不存在了
I've cancelled gravity out just by falling.
仅仅通过下落 我就挣脱了引力的束缚
If you understand that, then you'll understand gravity.
如果你能理解这一点 你便能理解引力
So it is possible, by the simple act of falling,
所以 通过这种简单的落体运动
to get a very different experience of gravity.
我们便能获得一番截然不同的引力体验
But this force of nature does more
但是这种自然之力
than just bring us back down to earth.
可不仅仅是将我们引回地面这么简单
Gravity also plays a role on the grandest of stages,
引力也在方方面面扮演着重要角色
because across the universe,
因为纵观整个宇宙
from the smallest mote of dust to the most massive star,
从极其微小的微粒 到质量巨大的恒星
gravity is the great sculptor
无一不出自引力的巧夺天工
that created order out of chaos.
它在混沌中创造出了秩序
Since the beginning of time,
自从有时间开始
gravity has been at work in our universe.
引力就进驻了我们的宇宙
From the primordial cloud of gas and cosmic dust,
以原始气团和宇宙尘埃为材
gravity forged the stars.
引力锻造了恒星
It sculpted the planets and moons,
它又造出行星和卫星
and set them in orbit around the newly formed suns.
并将它们放置在新兴恒星周围的轨道上
And gravity connects these
引力在庞大的星系中
star systems together in vast galaxies,
把这些恒星系统联♥系♥到一起
and steers them on their journey through unbounded space.
引导它们穿越这无垠的空间
Over the centuries,
经过数个世纪
our quest to understand gravity has allowed us
我们努力理解引力
to explain some of the true wonders of the universe.
这让我们能够解释宇宙中一些真正的奇迹
But at a deeper level,
但是在更深的层次上
that quest has also allowed us to ask questions
也使我们提出
about the origin and evolution of the universe itself.
关于宇宙自身起源和演变的问题
To understand how gravity works across the universe,
为了理解引力在宇宙中是如何作用的
we need look no further than the ground beneath our feet.
我们不必看远 只需审视脚下
Well, the first scientist to really think about it
第一位真正思考这问题的科学家
was Isaac Newton back in the 1680s,
是1680年代的艾萨克·牛顿
and he said this -
他是这么说的
"Gravity is a force of attraction between all objects".
万物之间皆有引力
Now, the force of attraction between these two rocks
很明显 这两块岩石之间的引力
is obviously very small, almost impossible to measure,
十分微弱 几乎无法测量
and that's because the force
那是因为这种力
is proportional to the masses of the objects.
是和物体的质量成比例的
These things are not very massive.
这些石头还不够重
But there is a more massive rock around here.
但这附近有一块大得多的岩石
It's the one I'm standing on, planet Earth.
它就是我现在站的地方 也就是地球
The mass of our earth generates a gravitational pull
地球的质量使它能产生地心引力
strong enough to sculpt the entire surface of the planet.
引力十分强烈 足以改变整颗行星的面貌
It causes water to gouge out vast canyons.
它引导水流开凿出大峡谷
It sets the limit for how high mountains can soar,
它限定了山脉能耸多高
and it shapes whole continents.
它塑造了整个大♥陆♥
But this invisible force does more than just shape our world.
但这看不见的力量不仅塑造了我们的世界
The skies are always changing,
咱们头上的苍穹变幻莫测
and the constellations rise and fall
夜晚的星空周而复始地上演着
in different places every night,
斗转星移的剧情
and the planets wander across the background of the fixed stars.
行星在以恒星为中心搭建的舞台上肆意徜徉
But throughout human history,
但纵观整个人类历史
there's been one constant up there in the night sky,
夜空中总悬着一个熟悉的面孔
because every human that's ever lived has gazed up at the moon
因为每个过来人 都曾抬头凝视那弯明月
and seen one face shining back at us.
亲历她那张光亮夺目的脸庞
The reason why we never see the dark side of the moon
我们之所以从未目睹月球的暗面
is all down to the subtlety with which gravity operates.
全源自引力使的小把戏
Millions of years ago, the moon rotated rapidly.
百万年前 月球飞快地自转
But from the moment it was born,
但是从它诞生的那一刻起
our companion felt the tug of gravity.
我们的卫星就受制于了引力
Just as the moon creates great tides in our oceans,
正如同月球让海洋潮起潮落
the Earth caused a vast
地球也在整个月球表面
tide to sweep across the surface of the moon.
引发了一次巨大的潮汐
But this tide wasn't in water.
但不同于潮水
It was in rock.
它是由岩石组成的
Imagine that this is the moon, and over there is the Earth.
假如这是月球 那里是地球
The Earth's gravity acts on the moon and
地球的引力作用于月球
stretches it out into a kind of rugby ball shape.
将它拉扯成橄榄球的形状
Now, the size of that tidal bulge
相对于地球来说
facing the Earth is something like seven metres in rock
这股石头浪潮的高度大约有7米
and then, as the moon rotates,
随着月球的自转
that bulge sweeps across the lunar surface.
这股岩潮横扫月球表面
I mean, imagine what that would look like here.
想像一下这会是什么一种样子
You'd see a tidal wave sweep
你会看见一波潮汐
across this landscape,
席卷这片地区