We live on a world of wonders,
我们生活在一个奇妙的世界里
a place of astonishing beauty and complexity.
一个美妙而复杂的世界
We have vast oceans, incredible weather,
我们有广阔的海洋 和令人难以置信的天气
giant mountains and spectacular landscapes.
巨大的高山和壮观的风景
If you think that this
如果你觉得所有的这些宏伟的景观
is all there is, that our planet exists in magnificent isolation,
仅仅是存在于我们星球上
then you're wrong.
那么你就错了
We're part of a much wider ecosystem that extends way beyond
我们是更广泛的生态系统的一部分
the top of our atmosphere.
它的扩展超出了我们的大气层顶端
I think we're living through the greatest age of discovery our civilisation has known.
我认为我们正经历着 一个最能够探索与发现已知文明的时代
We've voyaged to the farthest reaches of the solar system.
我们的航天器早已到达太阳系最远的地带
We've photographed strange new worlds,
我们已经拍下陌生的新世界
stood in unfamiliar landscapes, tasted alien air.
站在这不熟悉的地方 呼吸着陌生的空气
Now, the laws of physics are simple and they're universal.
现在 物理定律是简单通用的
What applies here applies everywhere else up there.
适用这里 适用于其他任何地方
But it's fascinating that they can manifest themselves
但它们却可以表现出
in so many different ways across the solar system.
如此众多的方式于整个太阳系
In this programme, I'm going to look at how the universal forces of nature
本集 我要去看看 大自然的普遍力量
that created all this can also wreak devastation across the solar system.
是如何在整个太阳系中搞建设 搞破坏的
How they can be the death of a planet...
它们是怎么搞死一颗星球...
..and how they can keep other worlds alive.
..怎么使其他世界充满活力
I can just see pieces of molten rock rising up just below my chin.
我才看到熔化的岩石碎片飞到我下巴下方
These forces are so far reaching, they bridge the depths of space
这些力量遥不可及 它们架建于深渊的太空
and transform a world long thought dead
穿过悠久的宇宙
into a world of perpetual change and everlasting youth.
进入一个不断变化 永远年轻的世界
The intense source of heat that powers that eternal change also
激烈的热量来源 永恒的变化
drives one of the most spectacular sights in the solar system.
形成太阳系最壮观的景点之一
太阳系的奇迹
生与死
I've come to one of Earth's natural wonders,
我来到地球的自然奇观之一
the Grand Canyon in Arizona.
亚利桑那州大峡谷
It's a place to be humbled by nature.
这地方只是大自然卑微的体现
Well, this is undoubtedly
无疑
one of the most beautiful places I've seen on Earth.
这是我在地球上见过的 最美丽的地方之一
From sunrise to sunset,
从日出到日落
the changing light brings this immense landscape to life.
阳光带来的变化让这巨大的风景荣发生机
I hear stories of people coming here at sunrise with tears in their eyes
我听说这里的人在日出时 他们热泪盈眶
at the majesty of the view, and I can see why.
在这如此威严的场景 我终于懂了
It's incredible to think that this enormous valley
很难想象 这巨大的山谷
was etched and carved
是被蚀刻和雕刻出来的
by the action of running water over just a few million years.
由奔腾的水 经过短短几百万年
Our knowledge of natural wonders like the Grand Canyon
我们对自然奇观的了解 像大峡谷
was once limited to our own planet.
曾受限于我们自己的星球
But the space age has brought new worlds into view.
但航天时代带来了新世界
This is Mars, the Red Planet.
这是火星 红色的星球
Fourth rock out from the sun, it has a canyon so vast
排位第四 它也有一个大峡谷
you could fit our own Grand Canyon into one of its side channels.
你可以将自己的大峡谷对比到这里的其中之一
Named after the space probe that first saw it,
空间探测器看到这些之后 于是命名
this is the Valles Marineris.
水手谷
8km deep and over 3,000km long,
8公里深 3000多公里长
on Earth it would run all the way from Los Angeles to New York.
如果在地球上的话 就是从洛杉矶到纽约
We're beginning to get a deep and quite profound understanding
我们逐步深入 获取了相当深刻的认识
of the way that Mars has evolved geologically because
火星的地貌是由于地质演变
we are now there, because we now have eyes and ears on the surface.
我们现在在那里 因为我们有了眼睛和耳朵在那
And there really is no substitute for actual exploration, for actually
确实也没有可替代的探索行动
going somewhere and touching it and taking pictures of it.
去实际地到达和接触它 并且给它拍照
Look at this picture.
看看这张照片
This is a picture of a sunset.
这是一张夕阳的照片
These are pictures of clouds.
这些都是云朵的照片
It's amazing to think these incredibly familiar-looking photographs
令人惊讶的是 这些照片难以置信的熟悉
were taken on the surface of Mars.
从火星表面拍摄的
This picture,
这张照片
or this amazing colour picture...
这惊人的图片颜色
I could have got a camera here and just snapped any picture
我可以在这里拿个相机 拍摄的任何图片
and it would have looked exactly like this one.
看起来都跟这个完全一样
In the Grand Canyon, you can see the Colorado River
在大峡谷 你可以看到科罗拉多河
running in the bottom of the valley
流经谷底
so you can understand how this landscape was made.
所以你可以理解 这些景观是怎么形成的了
Whereas here on Mars, there's no sign of any water.
而火星 目前没有任何水的迹象
So Mars is a puzzling place.
因此 火星很令人费解
Despite all the similarities between Mars and Earth,
尽管火星和地球间有这么多的相似之处
it's the differences between these two planets that are most telling.
但两颗行星之间的差别 是最能说明问题的
Mars is now a desolate dead wasteland,
现在火星是一个荒凉的死亡之地
a world where the processes that sculpted its familiar landscapes
一个景观如此熟悉的世界
seized up long ago.
在很久以前
It's fascinating for me as a physicist to see how
我非常着迷 作为一个物理学家 看看
the same basic simple laws of nature can play out
相同的简单基本的自然法则
in such radically different ways, and produce such astonishingly
在完全不同的条件 如何构成这种惊人的
varied and beautiful and violent and dead worlds
多样而美丽 暴力和死亡的世界
out there, across the solar system.
在整个太阳系中
The Big Island of Hawaii, in the middle of the Pacific Ocean,
夏威夷大岛 太平洋中部
holds the key to what happened to Mars.
掌握了火星上所发生的一切
This is the perfect place to witness how a planet can be kept alive
这是一处绝妙的地方 去见证星球是怎么通过
by nothing more than the simple flow of heat.
这种简单的热流来保持活力
You can smell the volcanic ash coming into the...
你可以闻到火山灰进入到...
into the helicopter. And everywhere you look, it looks like a...
进入直升机 到处都是你看 它看起来像..
It's almost like an apocalyptic scene.
简直就像世界末日
This volcano is Kilauea, which means spewing.
这火山叫基拉韦厄 意思是喷涌
It's been erupting almost continuously since 1983.
自1983年以来 几乎不断地喷发
In fact, you can see molten rock flowing down the side
事实上 你可以看到熔岩流经的
of the mountain just cutting a swathe through the trees.
山 从树林中杀出一大片
This might look like widespread destruction,
这有点像大面积的破坏
but volcanic eruptions are Earth's geological heartbeat.
但火山喷发就是地球的地质心跳
Active volcanoes make our planet a vibrant, living world.
活火山使我们的星球充满活力
That is the most spectacular demonstration
这是我见过最壮观的景观
of our planet being geologically alive that I've ever seen.
从地质学上看到我们的星球是活的
A few kilometres north of Kilauea,
几公里以北的基拉韦厄
you can see just what volcanic action can produce,
你可以看到火山活动能产生什么东东了
given enough time.
只需足够的时间
The islands of Hawaii were built entirely by volcanoes.
夏威夷群岛完全由火山建造
Today, these mountains are the largest volcanoes on our planet,
今天 这些山脉是我们这个星球上最大的火山
and we've seen landscapes just like this, on Mars.
我们已经在火星上看到类似的景观
It's quite an experience being 4km high.
四公里高 真是一个好体验
It makes you out of breath and you sniff a lot because your nose becomes...
它使你喘不过气来 你吸气 因为你的鼻子变得...
And makes you feel like you've had a few drinks.
感觉像是你喝高了
This is Mauna Kea,
这是毛克亚
one of the five volcanoes that make up the Big Island of Hawaii.
夏威夷大岛上的五座火山之一
I've known about it since I was very little
我很小的时候我就知道它
because it's one of the most famous observatories on the planet.
因为它是最有名的地球观测站之一
Everywhere you look, surrounded by our eyes to the cosmos.
这里到处 四周满目都是宇宙的世界
Although this mountain is 4km above the surface of the Pacific,
虽然这里是太平洋海平面以上4公里
it's actually 10km above the surface of the Pacific floor.
但它实际上是太平洋板块以上10公里
That makes it the highest mountain on Earth,
它才是地球最高的山峰
over a kilometre higher than Mount Everest.
超过珠穆朗玛峰一公里
But it is a tiny volcano compared to the biggest volcano on the surface of Mars.
但它是一座小火山 相对于火星表面最大的火山
This is Olympus Mons,
这是奥林匹斯
named after Mount Olympus, the mythical home of the Greek gods.
奥林匹斯山 是希腊神话中神的家
This vast outpouring of lava stretches over 550km across,
这种巨大的熔岩横跨550公里宽
but it's the height of this volcano that is breathtaking.
但这一火山却是惊人的高
It soars 25km into the Martian sky,
两万五千米高耸入空
nearly three times the full height of Mauna Kea.
近3倍Mauna Kea的高度
But Olympus Mons isn't just the tallest volcano in the solar system,
奥林匹斯不仅是太阳系最高的火山
it's the highest mountain we know.
也是我们目前所知最高的山脉
There are striking similarities between the volcanic landscapes
火山之间还有惊人的相似之处
here on Hawaii and the giant volcanoes found on Mars.
夏威夷这里的和火星上发现的
These similarities can be traced back billions of years
这些相似之处可以追溯到数十亿年前
to the fiery birth of the solar system.
太阳系出生之时
All this heat you can see driving this spectacular volcanic activity
所有这一切驱使这壮观火山活动的
is a relic, a hangover of the Earth's formation.
是一些残渣 是地球形成后的遗留物
Now, all the rocky planets - Earth, Mars, Venus, Mercury - were formed in the same way.
现在 所有的岩石行星 -地球 火星 金星 水星
They came from a collapsing dust cloud over 4.5 billion years ago.
以同样的方式形成 它们来自45亿年前一片坍塌的尘埃云
With the ignition of the sun, our solar system was born.
随着太阳的点燃 太阳系诞生了
Little by little, the rocky bodies grew,
渐渐地 岩石的身躯一点点形成
falling together under their own gravity.
在自身引力下一起下沉
This process not only generated immense amounts of heat,
这一过程不仅产生了巨大的热量
it also delivered radioactive material to the cores.
也释放了放射性材料到核心
These two ancient sources of heat power Earth's volcanoes to this day,
这两个古老的热量来源就是如今地球火山的能量
but the volcanoes on Mars are little more than a petrified memory of a distant past.
但火星上的火山在遥远的过去就成为了回忆
When we look down on the surface of Mars,
当我们往下看火星表面
we see no evidence of this kind of volcanic activity.
我们看不到这样的火山活动的证据
As far as we can tell, Mars is a dead world.
据我们所知 火星是一个死亡世界
Mars must have had similar inner heat to Earth to build its volcanoes.
火星上肯定有过类似地球内部的热量 来建造自己的火山
Yet something obviously happened
然而 一些明显的事发生了
to stop the Red Planet's geological heartbeat.
红色星球的地质心跳停止了
Now, as everyone who's left a hot cup of tea sat on the kitchen table knows,
现在 大家都知道 放一杯热茶在餐桌上
hot things lose heat to their cooler surroundings,
热的物质会失去热 在比它们冷的环境
and what's true for cups of tea, in physics is also true for planets.
同样的物理学也适用于行星
This is hot and that up there - space - is cold.
这是热的 而且在那里 -太空 - 是冷的
So planets lose heat to space.
因此 行星散热到空间里
Mars is a much smaller planet than the Earth.
火星是比地球小得多的星球
It's about half the diameter, it's an eighth of the volume,
它的直径大约是地球的一半 体积排第八
so there was much less heat trapped in there to begin with.
所以刚开始这里的热量也少得多
Now, planets lose heat to space through their surfaces,
现在 行星通过它们的地表散热到空间
and smaller things have a larger surface area
较小物体的表面积与体积的比率
in relation to their volume than big things.
大于较大的物体
So that means that Mars will lose its heat to space much quicker than the Earth does.
因此说明 火星失去热量比地球快得多
When the interior of Mars grew cold,
当火星内部变冷
the mighty volcanoes lost their lifeblood.
强大的火山也失去了它们的生命之源
The Red Planet's geological heart died,
红色星球的地质心脏死了
and millions of years ago, the surface of Mars ground to a halt.
数百万年前 火星地表停止了活动
The fate of a whole planet was destined
注定了整个星球的命运
by the simplest of laws of physics.
被简单的物理定律
Since the dawn of human history, we've been able to gaze up into the night sky,
自从人类历史开始 我们就仰望星空
but we're lucky because we're the first generation that's been able
但我们很幸运 因为我们是第一代
to build machines to actually go to those planets and moons.
能建造机器实际地去到这些行星和卫星
And we've found that they're more beautiful, more violent,
而且我们发现 它们更美丽 更猛烈
more magnificent and fascinating
更宏伟 更迷人
than we could have possibly imagined.
远非我们所预想
The more worlds we study, the more we realise
我们研究越多的世界 我们越是意识到
that our solar system is a cosmic laboratory.
太阳系只是宇宙的实验室
Even the slightest differences in size or position
即使是大小或位置的轻微差异
can create a world radically different from its neighbours.
也可以建立一个与毗邻完全不同世界
So here on Earth, we have one beautiful manifestation of how those
所以在地球上 我们有这些美丽的风景
simple laws of nature can play out, how they can build a planet.
这些简单的的自然法则是怎样发挥作用的 如何塑造星球的
In Mars we have another example.
火星 我们还有一个例子
What happens when you take a planet that's smaller than Earth
当你让一颗比地球小的星球
and move it further away from the sun?
离开太阳到更远的地方 会发生什么呢?
It loses its heat more quickly and it becomes geologically inactive.
它更快地失去它的热量 地质活动也变得不活跃
But what would happen if you took a planet just like the Earth
但如果让一颗类似地球的星球
and moved it a little closer to the sun?
靠近点太阳呢?
Well, we know of such a planet.
好 我们知道有这样的一颗行星
It's the brightest point of light in our night sky.
它是我们夜空中最明亮的一点
So similar in size to our own world,
大小与我们类似
this planet has been called Earth's twin.
这个星球被称为地球的同胞
This is Venus.
金星
Orbiting closer to the sun, Venus was named for its shining beauty.
它的轨道更接近太阳 它的名字就是因为它美丽的光辉
But our planetary twin hides its true identity
但是 它隐藏了它真实的身份
beneath a thick blanket of cloud.
在其厚厚的云层下面
Over the last 4.5 billion years,
过去45亿年里
Venus has turned into an unimaginably oppressive world.
金星已经变成一个难以想象 受压迫的世界
The atmosphere is so dense that the pressure is crushing.
这里的大气很稠密 气压很高
It's 90 times atmospheric pressure here on Earth.
是地球大气压的90倍
Now, Venus takes 243 days to rotate once on its axis.
现在 金星需要243天才能自转一圈
That means its day is longer than its year.
它的一天比一年还长
So Venus has the hottest average surface temperature,
因此 金星平均地表温度是最热的
other than the sun's, anywhere in the solar system - 470 Celsius.
除了太阳 太阳系的任何地方 - 470摄氏度
I've come to India, to a place called the Deccan Traps.
我在印度 一个叫Deccan Traps的地方
Hidden in this lush green landscape are tantalising clues
隐藏在这郁郁葱葱的绿景之下 是诱人的线索
to understanding how immense heat caused Venus to choke to death.
了解巨大的热量是如何导致金星之死
When you look at this landscape today,
今天 当你看到这个风景
it's incredibly peaceful and beautiful, rolling green hills,
很安宁 很美丽 群山起伏
but I think it's astonishing to think
但我觉得 让人惊讶的是
that everything you see down there is lava.
你看到的这一切都是熔岩
This whole landscape, half a million square kilometres of it, was created
整个景观占地50万平方公里
in an ongoing volcanic eruption that lasted for a million years.
创建于持续了一万年的火山爆发
If you take away the green foliage, the underlying landscape of lava
当你拿走这些绿色屏障 就会看到底层的熔岩
is actually very similar to what we see on Venus.
看上去和金星很像
Using radar to peer down through the clouds,
使用雷达 透过云雾
the surface of Venus was finally revealed.
金星地表终于显露出来
It's covered with floods of solid lava, just like we see in India,
它覆盖着凝结的熔岩 就像在印度那样
but on a scale many thousands of times larger.
但却是数千倍的大
We've also counted over 50,000 volcanoes,
我们计算出有超过50 000座火山
the most on any planet in the solar system.
是太阳系中最多的
Venus is a similar size to Earth,
金星与地球大小相近
so it may still have a hot geological heart
因此它也许还有火热的地质心脏
powering its volcanoes but as yet we haven't witnessed any eruptions.
为火山提供动力 但目前我们还没看到任何喷发
The ancient floods of lava we see on Venus
金星上古代的熔岩流和这里印度的
and here in India were created in much the same way.
都是以同样的方式创造出来
For both planets, this was volcanic activity in overdrive.
这两个行星 地球也曾是火山活动过度
The eruptions here in India 65 million years ago
印度6500万年前的火山爆发
affected the Earth's climate so much that they're thought to have played
很大程度上影响了地球的气候 同时也被认为
a major role in the mass extinction events at the end of the cretaceous period,
在白垩纪晚期的大灭绝中 扮演了重要角色
which wiped out over two-thirds of the species on Earth.
地球超过三分之二的物种灭绝
Now, life on Earth recovered but Venus wasn't so lucky.
现在 地球上的生命复苏了 但金星没有那么幸运
The intense volcanic activity on both planets
两个行星强烈的火山活动
didn't just blast out molten rock.
不只是熔岩喷出来
It also released copious amounts of gases, like carbon dioxide.
也释放了相当数量的气体 如二氧化碳
But slight differences in the way the laws of physics played out
相同的物理定律所造成的后果 在金星略有不同
on Venus helped push our cosmic twin down a path of no return.
使得它走上了一条不归路
Venus and Earth reacted very differently to the same kind of volcanic cataclysm,
相同的火山运动中 金星和地球的反应非常不同
and the reason for that is something that happens so often on Earth
原因在于地球经常有某些事发生
that we take it for granted, and just moan about it.
一件理所当然的 仿佛只是呻吟了一下的事
Rain plays a significant role in keeping our planet a pleasant place to live.
雨在保持我们星球宜人的环境 发挥了重要作用
Acting as part of a global recycling system,
是全球循环系统的一部分
rain keeps our atmosphere in balance,
雨使我们的大气层保持平衡
washing out the potent greenhouse gas, carbon dioxide,
洗出温室气体 二氧化碳
ready to be locked away in rocks in our oceans.
锁定到岩石 海洋
But on Venus, the laws of physics have made it impossible
但在金星 物理定律无法通过
for rainfall to cleanse its atmosphere.
降雨来净化大气
In fact, there's no liquid water at all.
因为 那里根本没有液态水
Venus lost its water essentially because it's hotter than the Earth.
金星失去水 实质上是因为它比地球热
You see, temperature is just a measure of how fast things are moving around.
你看 温度只是衡量事物运动快慢的尺度
So on Venus the oceans would have evaporated into the atmosphere
因此 金星的海洋会蒸发到大气中
and that water in the atmosphere would be moving around
而大气中的水分会移动得
extremely quickly, simply because it's hot.
非常快 就因为它温度高
And Venus is so close to the sun and so hot,
金星离太阳太近导致温度很高
those water molecules are moving so fast that the gravity of the planet
这些水分子移动得太快 使得引力
can't continue to hold them in the atmosphere,
无法在大气层中束缚
and so they simply escape off into space.
于是它们就脱离到了太空
With no water, there is no rain on Venus.
没有水 金星就没有雨
For billions of years, there has been nothing
几十亿年来 没有任何物质
to temper the build-up of volcanic gases in its atmosphere.
可以减缓进入大气的火山气体
Venus ended up cocooned in a thick, high-pressure,
金星最终就有了一层厚厚的 高压的
dense blanket of carbon dioxide,
浓密的二氧化碳
and that made the temperature rise and rise and rise,
使得温度上升 上升 再上升
turning Venus into the hell-like world we see today.
把金星推向了 如今这个地狱般的世界
Compared to scorched Venus and frozen Mars,
高温的金星和冷冻的火星相比
our home is a very special ball of rock.
我们的家园真是个非常特殊的大石球
Although governed by the same universal set of rules,
尽管都受同一通用规则控制
our planet is not too big, not too small,
我们的星球不太大 也不太小
not too hot, not too cold.
不太热 也不太冷
Earth has been called the Goldilocks planet
地球被称为"金发姑娘"
because everything is just right.
因为这一切都恰到好处
Our world is unique but it doesn't exist in splendid isolation.
我们的世界是独一无二的 但它不是与世隔绝的
It is intimately connected with its cosmic neighbours.
它与宇宙邻居密切相连
Earth is not the master of its own destiny and it never has been.
地球不是它自己命运的主人 从来都不是
The life and death of our planet is influenced by forces
生命与死亡 不过是受到一种
emanating from the very depths of space.
来自空间深处力量的影响
As we better understand our place in space,
当我们更好的了解我们在太空的位置
we've come to realise that our sharing of the same physical laws
我们就意识到 相同的物理法则
with the other worlds in the solar system
在太阳系的其他世界
isn't the only connection we have with them,
不是我们与它们的唯一关系
because those same laws lead to a direct physical connection
因为相同的法则导致了地球和其他外部世界
between the Earth and the other worlds out there
有了直接的物理关系
that is subtle, is complicated, but can sometimes be extremely powerful.
这是微妙的 复杂的 但有时也会非常强大
Out in the farthest reaches of the solar system are vast worlds
在太阳系最远的地方 是广阔的世界
that have a direct impact on our very existence.
对我们的生存有着直接的影响
This is our sun from ten billion kilometres away -
离太阳100亿公里外
just another star in a sea of stars.
茫茫星海中的一员
But as you head towards the light, you enter a realm of giants.
但当你仰望星空 将进入巨人的世界
The furthest planet from the sun is icy Neptune,
太阳系最远的行星 冰冷的海王星
with its thick, blue methane atmosphere.
有着厚厚的 蓝色的甲烷大气层
Uranus comes next, the only planet that lies on its back.
接下来是天王星 唯一一颗自转轴躺着的行星
Further in towards the sun, and the planets get even bigger.
继续向太阳靠近 到达更大的行星
Saturn, with its beautiful rings of ice.
土星 和它美丽的光环
Finally we reach the king of the giants - Jupiter.
最后 我们到达太阳国王中的巨人 - 木星
Jupiter is the largest planet in the solar system,
木星是太阳系里最大的行星
so big you could fit Earth inside it over 1,000 times.
大得可以塞进1000多个地球
It's made up of the same stuff as our sun - hydrogen and helium -
它与太阳的构成一样 - 氢和氦
the most common elements in the universe.
宇宙中最常见的元素
In its thick churning atmosphere,
在其厚密的旋转大气层里
gigantic storms have raged for centuries.
巨大的风暴已经持续了几百年
Now, astrologers have said for years that Jupiter influences our lives,
占星学家说 多年来木星一直影响我们的生活
but we now have scientific evidence that this mighty planet does have
现在我们确实有科学证据表明 这巨大的行星
a significant connection with our own small world.
确实与我们这个小世界有重大的关系
Jupiter is so different to our planet -
木星在行星中是多么的与众不同
you know, a big ball of gas, half a billion kilometres away -
你知道 一个大大的气球 在50亿公里之外
it's difficult to see how it could have anything to do with us at all.
很难看出它和我们有什么联系
But despite the fact that astrology is a load of rubbish,
但是 尽管占星术都是一些废话
Jupiter can, in fact, have a profound influence on our planet
木星事实上 与我们星球牵涉巨大
and it's through a force that, well, surrounds us and penetrates us
并且它通过一种力量 包围我们 穿透我们
and binds the galaxy together - gravity.
把星系都束缚在一起 -引力
Gravity is one of the fundamental forces of nature.
引力是自然界基本力之一
It exists between all objects, and the effects
它存在于所有物体
of a gravitational field extend way beyond the planet that creates it.
跨行星来进行影响
Gravity is by far the weakest force of nature.
引力是目前已知最弱的力
But it's the only force that has an influence across the entire solar system,
但却是唯一在整个太阳系作用的力
and that's because, although it's weak, it has an infinite range.
虽然它弱 作用范围却是无限的
It never quite goes away.
它永远不会消失
So, no matter how far you go, you feel the force of gravity
所以 不管你走多远 都能感受到
as a planet, although it drops and drops and drops away.
星球的引力 尽管它一直减少减少
Jupiter has the most powerful gravitational field of all the planets,
木星在所有行星中 拥有最强大的引力场
and it's the gas giant's gravity that can directly influence
它巨大的引力能够直接影响到
the orbits of asteroids and other wandering space debris.
小行星的轨道和其他空间碎片
Jupiter is so massive, by far the most massive planet in the solar system,
木星是太阳系最大的行星
that its gravitational field can have a profound influence on passing interplanetary stuff.
它的引力在行星之间也有重大影响
It can do three things.
它可以做三件事
Firstly, it can capture the stuff, literally hoover it up.
首先 它可以捕捉物体
Secondly, it can deflect the stuff,
其次 它可以偏转物体
such that it throws it out of the solar system.
这样 它就能把物体引出太阳系
But thirdly, and most importantly for us,
第三 最重要的是
it can deflect stuff onto a direct collision course with our planet.
它可以偏转飞向我们地球的物体
Influenced by Jupiter's gravity,
受木星的引力
today, right now, we're highly vulnerable from asteroid impacts.
现在 我们依然受到小行星撞击的威胁
But we do have sentinels standing guard.
但有了哨兵为我们站岗
On top of the mountain of Heleakala on the Hawaiian honeymoon island of Maui,
在Heleakala山顶 夏威夷的蜜月毛伊岛
I've come to see Professor Nick Kaiser, who's searching
尼克凯撒教授 他一直研究
our solar system for potentially hostile space debris.
太阳系潜在的空间碎片的危险性
The prime task is to try and find killer asteroids,
首要任务是寻找杀手级小行星
things that are out there in the solar system
在太阳系那边
that might hit the Earth.
有可能撞击到地球
There's an air of Hollywood about it, isn't there, in some sense?
有种好莱坞大片的感觉 是吗?
Well, that's right. I would say a lot more resources have been spent
是啊 很多的资源都花在了
on making movies about killer asteroids than actually finding them.
拍这种电影上 比实际研究都多
Anything that's a kilometre in size, if it hit the Earth it would be devastating.
凡是一公里的大小 撞到地球的话 都是灾难性的
It would probably kill nearly everyone on the planet.
它几乎能毁灭一切
Each night, using a revolutionary billion-pixel digital sensor,
每天晚上 使用10亿像素的数字传感器
the team scans a vast swathe of the sky.
搜索队就扫描某一片天空的区域
Mind your head!
小心头!
They're looking for any unidentified objects that might be heading our way.
他们正在寻找可能撞向我们的天体
So any one of these points of light could in fact be an asteroid?
所以这些光点都可能是小行星?
That's right. And it's very likely,
很正确 并且是非常有可能的
in fact, it's almost certain that there are asteroids in that image.
事实上 在图片中基本就可以判定它们是小行星
The problem is, how do you figure out which ones they are?
问题是 怎么找出有威胁的呢?
Yeah.
是啊
The camera captures several images of the same patch of sky taken minutes apart.
摄像头每隔几分钟 在同一片天空拍摄一张
The team can then see if anything has moved,
拍完几张后 这样就能看到哪些在动了
relative to the background of stars.
相对于恒星
What we've done here is taken two images and subtracted them,
我们所做的就是两张图相抵消
and you see the stars have nearly all gone away.
恒星基本全部消失
There's a couple of interesting things left.
只有一些有趣的东西留下了
If you look over here, you see a dark thing and a white thing,
看这里 一个黑 一个白
so that's something which was THERE in the first image
所以第一张图 那里(白点)有东西
and THERE in the second image. And there's another one here.
第二张那里(黑点)也有 这里还有个
So even on this tiny patch of sky, we've already detected two objects.
所以即使是这么小片天空 我们就发现了2个天体
What that means is, when we do that kind of analysis
意思是 当我们做类似的分析
on a whole field of view, we'll detect hundreds of objects.
在整片领域 我们就能发现数以百计的天体
The beauty of our night sky belies the potential danger it holds in store.
美丽的夜空隐藏了如此危险的东东
Over 2,000 objects have been identified that pass close to the Earth,
已经确定有超过2000个天体 会在地球附近掠过
with something like 400 that could be on a future collision course.
400个可能会在未来撞击
And all of these menacing lumps of rock, at some point,
所有这些有威胁的石头 某些情况下
come under Jupiter's gravitational influence.
会受到木星引力的影响
Now, if you ever needed a demonstration of how congested the space is near the Earth,
现在 地球附近的空间有多拥挤呢
just look at this movie of the near-Earth objects,
看下这里的近地天体
so here's Mercury, Venus, the Earth, Mars and out here is Jupiter.
这里是水星 金星 地球 火星和木星在这里
Here's the asteroid belt, but look at the congestion in there.
这里是小行星带 但是看看这里拥挤的地方
Every one of those points of light is an asteroid that we know of.
每个亮点都是我们已知的小行星
Just look at the Earth swimming through them, so when you look up into the nice clear night sky and
看下地球和它们 当你抬头望着星空
you want to be reassured that we're all nice and safe,
你会觉得很安详 我们都很安全
just remember this movie.
记得这段视频
Our planet is on a deadly journey.
地球在一个生与死的旅程中
Earth is trapped in a cosmic game of dodgeball as it orbits the sun,
地球被困在一个躲避球的游戏里 因为它的轨道绕着太阳
a game where the gravitational stranglehold of Jupiter regularly throws asteroids our way.
受到木星引力 小行星会时不时飞向我们
Jupiter's gravitational influence on passing space debris
木星的引力影响了这些空间碎片
has made our planet a world under constant bombardment.
使地球不断地受到攻击
One of the most famous meteorite impact sites is the Barringer crater in Arizona.
其中亚利桑那州巴林杰陨石坑 是最有名的陨石撞击地点之一
50,000 years ago,
50 000年前
a 300,000 ton, 50 metre in diameter lump of iron and nickel entered the Earth's atmosphere
一块30万吨 直径50米的铁镍石冲入地球大气层
and made this crater, and it should remind us
制造了这个陨石坑 它提醒我们
that our environment doesn't just stop at the top of our atmosphere.
我们的生存环境不只局限于大气层底下
Our environment stretches out into the solar system,
还扩展到太阳系
to the very edges of the solar system, to wherever this rock came from.
到达太阳系的最边缘 到达这块石头的源头
In the grand scheme of things,
在这些大个子里
the asteroid that struck here was relatively small and innocuous.
小行星袭击相对来说微不足道
But there are much larger impact craters hidden in Earth's landscapes
但这风景之下 某些陨石坑有着大得多的影响
that have far more devastating tales to tell.
一些毁天灭地的故事
200 years ago, white settlers crossed the ancient Appalachian mountains here in America
200年前 白人殖民者穿过古老的阿巴拉契亚山
to seek new land out west.
去寻找西边的新土地
Little did they know what they were walking into.
他们走进了他们不了解的地方
Well, this place to me feels like the very definition of small town America.
这地方很像美国的小城镇
It's on the border between Virginia, Kentucky and Tennessee.
它在弗吉尼亚州 肯塔基州和田纳西州的边界上
It's the kind of town where you feel that
一种城市的感觉
nothing much has changed for the last 100 years.
在过去的100年里没啥改变
But this place was the site,
但是 这个地方的位置
way back in history, of a violent cosmic intervention.
历史上是暴躁之地
This is Middlesboro, Kentucky.
米德尔斯伯勒 肯塔基州
It's a town built inside a meteorite impact crater.
建立在陨石坑的一个小镇
The asteroid that struck here would have been huge, about half a kilometre across,
50公里宽巨大的小行星袭击过这里
hitting the Earth well over 200 million years ago.
在200万年前
I find it fascinating that when you look out of this view, you don't really see an obvious crater.
有趣的是 你看不出这里有明显的陨石坑
And indeed, it wasn't until the 1960s that anybody had any idea that there was
事实上 20世纪60年代前 没人有过这样的想法
a colossal impact from space
从天空袭来的巨大撞击
just over there, centred right on the 18th hole of the golf course.
就在那边 就在18洞高尔夫球场中央
We now know where the giant asteroid that struck here could have come from.
我们现在知道这巨大的小行星来自何方了
Located between Jupiter and Mars is a vast reservoir of rocky debris that forms the asteroid belt,
木星和火星之间 有巨量的岩石碎片 从而形成了小行星带
and it's this ancient rubble that Jupiter, our neighbourhood giant, can nudge towards the Earth.
木星 我们的巨人邻居 可以把它们推往地球
Well, here's my model of the solar system.
嗯 这是太阳系模型
There's the sun in the middle,
中间的太阳
then the Earth, Mars, Jupiter,
然后 地球 火星 木星
and the asteroids sort of scattered in between the big region
小行星带散布在火星和木星间
between Mars and Jupiter.
广大的区域
In fact they extend over 150 million miles,
事实上 它们超过150万英里(240万公里)宽
which is further than the distance from the Earth to the sun.
比地球到太阳的距离都要长
This is my coffee, by the way, which doesn't represent anything.
顺便说一下 这是我的咖啡 不代表什么
I'll put it over there. But now and again,
先放到一边 那么现在
because of collisions in the asteroid belt, a stray asteroid
因为小行星带的碰撞 一颗流浪的小行星
will get thrown into the position where they keep rhythmically meeting Jupiter over and over again.
被甩到这里 有节奏地一遍又一遍与木星会面
And because Jupiter is such a massive planet,
由于木星是非常庞大的行星
that means that it gets a kick, it gets a gravitational kick.
意味着 它有了上帝之手 它用引力碰了一下
And that changes the orbit of these asteroids and over time, their orbit
改变了这些小行星的轨道 随着时间推移 它们的轨道
can become, well, elongated or elliptical rather than circular.
可以变成 嗯 椭圆形而非圆形
That means that they can get thrown
这意味着 它们可以飞进
into the inner solar system and cross the orbits
太阳系的内区域 与内行星的
of the inner planets, including the orbit of the Earth.
轨道交叉 包括地球的轨道
And you get a potentially catastrophic collision.
我们就有潜在的灾难性撞击了
Jupiter was once thought to be our protector,
木星曾经被认为是我们的保镖
its enormous gravity swallowing up dangerous asteroids.
其巨大的引力足以吞噬危险的小行星
Yet we now realise its gravitational influence can propel some of those asteroids in our direction.
我们现在意识到 它也可以使小行星飞向地球
But surprisingly, catastrophic impacts with space debris might not be a bad thing,
神奇的是 空间碎片的灾难性碰撞未必是坏事
at least, in Earth's past.
至少 在地球的过去
Impacts from space shaped our planet.
来自太空的撞击塑造了我们的星球
They made our world what it is today.
它们创造了如今这个世界
Take life on Earth, for example.
例如 给地球带来了生命 (外星人的种? -_-b)
Now, it's possible, or probable even,
它可能 甚至很可能
that impacts on a colossal scale changed the climate so much
在很大程度上改变了气候
that huge swathes of life on Earth were wiped out,
使地球大量生命灭绝
creating ecological niches into which other species could evolve -
接着又诞生了其他能进化的物种
us, for example.
例如 我们
It's incredible to think that a planet
难以置信 它作为一颗行星
half a billion kilometres away could dictate the fate of our world.
在50亿公里之外 掌握着我们世界的命运
Jupiter's immense gravity bridges the depths of space
木星巨大的引力纵深于太空
and even though its power could one day devastate Earth,
尽管有一天它会摧毁地球
that same gravitational field breathes life into other corners of the solar system.
同样的引力场 在太阳系的角落 有了生命
For better or worse,
无论好坏
Jupiter's powerful gravitational field has had a direct influence on our planet.
木星强大的引力场直接影响了我们的星球
We're part of a much wider ecosystem that extends to the very edges of the solar system,
我们只是一个扩展到太阳系边缘 更广泛的生态系统的一部分
and that ecosystem is bound together by the force of gravity,
由引力束缚到一起的生态系统
and it's gravity that has power to bring worlds to life.
它的引力也给世界带来了生命
Our understanding of the solar system began much closer to home.
我们了解太阳系始于最靠近家的地方
Gazing down at us, it was our moon, with its regularly changing face,
它凝视着我们 这就是我们的月球 其周期变化的脸
that first fired our interest in worlds beyond our own.
第一眼就注意到它
When we could look further out, we discovered the solar system was full
当我们看到更远 发现太阳系充满了
of moons, each invisibly connected to their parent planets by gravity.
月亮 每一个都用无形的力量连接着它们的母行星-引力
Our moon is a cold, geologically dead world, but the powerful gravitational bond
我们的卫星是冷的 无地质活动 但强大的引力约束着
that exists between another moon and its parent planet has done something astonishing.
另一颗卫星和其母星 完成了一些很High的事
It has brought this moon to life,
给这颗卫星带来了生机
making it the most violent place in the solar system.
使之成为太阳系最狂暴的地方
400 years ago, it was Galileo who first looked up at the night sky through a telescope.
400年前 伽利略第一次通过望远镜仰视夜空
Turning his attention to Jupiter, he noticed that this giant planet was not alone.
当他注意到木星 发现这巨大的行星并不孤单
Oh, yeah!
哦 是啊!
Absolutely magnificent.
绝对壮观
You see a disc surrounded by...
你看到周围...
Well, I can see three points of light.
哇 我可以看到三个光点
Galileo, over several nights, saw four points of light.
伽利略 连续几晚的观察 看到了4个光点
And he correctly surmised that those are actually moons, other worlds in orbit around Jupiter.
他推测 这的确是卫星 围绕着木星
Jupiter's four largest moons are named after the four lovers of the Greek god Zeus.
木星的四大卫星以希腊神宙斯的四个情人命名
Furthest out is Callisto.
最远的是Callisto(木卫四)
Then there's huge Ganymede, the largest moon in the solar system.
巨大的Ganymede(木卫三) 太阳系最大的卫星
Next is icy Europa,
接着是冰冷的Europa(木卫二)
and finally, the small, yellow-tinged moon nearest to Jupiter, Io.
最后 小小的黄色星球 最接近木星的卫星 Io(木卫一)
So the legend goes, Zeus tried to protect his lover, Io, by turning her into a cow
传说 宙斯为保护他的情人 Io 将其变成一头牛
to hide her from the jealous gaze of his wife, Hera.
以躲避他妻子赫拉嫉妒的目光
But it didn't work, and Hera sent a gadfly to torment Io.
但没有成功 赫拉派牛虻来折磨Io
And it was prescient in a way to name that satellite Io, the tormented moon.
这名字对于木卫一真有先见之明
Because we've since learned that it is indeed an incredibly tormented world.
因为我们已经了解 它确实是个难以置信的折磨的世界
For 400 years, we expected Io to be as dead as our own moon.
400多年来 我们以为木卫一也是跟月亮一样毫无活力
But in the late 1970s, when the first spacecraft passed by Jupiter,
但在 70年代末 当第一艘飞船经过木星
we finally saw Io up close.
我们终于近距离看到了木卫一
But it didn't make any sense, as here was a moon with no meteorite impact craters.
但令人费解的是 它作为卫星居然没有陨石坑
Now, it's impossible to believe that Io could have escaped
现在 我们是不可能相信木卫一能逃过
the bombardment that we see on our moon and practically every
我们所看到的轰击 我们的月球和几乎每一颗
other body in the solar system, so the only explanation is that that surface is young.
太阳系的星球 所以唯一的解释是 它的地表很年轻
It must have been recently produced, and that in turn means that Io,
那一定是最近的杰作 反过来 意味着木卫一
that tiny moon of Jupiter out there, must be a geologically active world.
一颗小小的木星卫星 必须是个地质活跃的世界
The truth about Io would blow us away.
关于木卫一的真相 让我们大开眼界
We may not have stood on Io, but there are places we can go here on Earth to help unlock its secrets.
我们是不可能站在木卫一了 但地球有一些地方
This is Ethiopia in East Africa.
可以解开它的谜团 东非埃塞俄比亚
We're being flown out by military helicopter to the very hot,
我们的军用直升机 飞行在很热
very inhospitable, Afar region in the north-east of the country.
很荒凉的 该国东北部的阿法尔地区
And this is what I've come to see.
这些就是我要看的
It's one of the rarest geological phenomena on our planet,
这是我们星球上最罕见的地质现象之一
a volcano with a lake of molten lava.
一座拥有熔岩湖的火山
As the sun goes down, the lava lake comes to life.
随着太阳下山 熔岩湖变得活跃
This volcano is called Erta Ale by the local Afar people.
这火山被当地阿法尔人称为Erta Ale
It means "smoking mountain".
意思是"吸烟山"
For many, this place is a vision of hell.
对许多人来说 这个地方就是地狱的场景
Yet it holds the key to understanding Io, a world over half a billion kilometres away.
但它是了解木卫一的关键 一个远离50亿公里的世界
This hot, tortured landscape of lava will be our home for the next three days.
这种高温的 熔岩景观 将是我们未来3天的家
Temperatures here reach 50 Celsius in the shade and we're camping right on top of the volcano.
即使是遮荫处 气温也高达50度 我们的营地正好在火山口上
But we're in good hands, as Io specialist Dr Ashley Davies is part of the team.
但是我们有好帮手 木卫一专家Ashley Davies博士也在团队
It is absolutely spectacular, isn't it?
绝对的奇观 不是吗?
Extraordinarily beautiful. You feel like you're looking into the core of the planet.
格外美丽啊 当你看到地球的核心
It's a window into the interior of the Earth, so magma is rising up
这里是窥视地球内部的窗口 岩浆正在升起
from some kilometres down, circulating through the surface and then sinking back down again.
从下面几公里处 通过表面循环 然后再次下沉
It is very difficult to breathe, it's very acidic and very bitter.
这里很难呼吸 这气体非常酸 非常痛苦
The magma has gases in it,
岩浆中有气体
and as it comes up to the surface, just like when you pour
当它冒出表面 就像当你
out a bottle of Coca-Cola, the gases come out.
倒可口可乐时 冒出气体
So what we have here is sulphur dioxide, hydrogen sulphide,
所以这些都是些二氧化硫 硫化氢
water vapour, carbon dioxide, coming out of the magma
水蒸气 二氧化碳 从岩浆散出
before the magma then cools and sinks down, and that's what we're breathing now, it's incredibly unpleasant.
在岩浆冷却前 然后下沉 这气体呼吸着真奶奶的不舒服
This volcanic phenomenon is a product of immense amounts
这里火山现象是由于巨大数量的
of primordial heat escaping from inside our planet.
从地球内部散出的原始热量造成的
Yet we have seen something similar in the far reaches of the solar system.
然而 类似的情景也在太阳系遥远的地方发生
Io is the same size as our moon and should be a cold, dead world.
木卫一和月球大小相同 应该是寒冷 死的世界
Yet our first glimpses of Io revealed it as seething with heat, alive with volcanic activity.
然而 当第一眼看到木卫一时 发现它有剧烈的火山活动
Just one of the many lava lakes on Io releases more heat than all Earth's volcanoes put together.
只是木卫一众多熔岩湖中的一个 它释放的热量 就比地球上所有火山释放的总量都要多
If we were to stand on the surface of Io now,
如果我们是站在木卫一的表面
what would be the similarities and what would be the differences?
有什么异同呢?
The lake would probably appear very, very similar to this, except for the scale.
那熔岩湖和这个将非常 非常的类似 除了大小
The lava lakes on Io are vastly larger.
木卫一上的熔岩湖极其巨大
The biggest one, we think, is 180km in diameter.
最大的一个 直径180公里左右
180km? So that would stretch way... obviously way beyond the horizon on Earth!
180公里? 那将延伸到...明显超过地球上的地平线!
Yeah, it's almost beyond description,
是的 难以用言语表达
to see something that size and it's just this huge pool of molten lava.
熔岩多得无法想象
Io is the most volcanic place in the solar system,
木卫一的火山是太阳系里最猛烈的
endlessly pumping out heat into the cold vacuum of space.
无休止地抽取热量 散发到宇宙真空
But what's really interesting is that it's so small that it shouldn't be volcanic at all.
有趣的是 它体积那么小 理论上火山不应该有
It was one of the greatest surprises of planetary science
这对行星科学真是天大的惊喜
when these massive volcanoes were discovered on Io.
当发现木卫一数目众多的火山时
Mighty planets like Mars - has big volcanoes.
火星 也有大火山
They're not erupting anymore, they haven't erupted for a long time.
它们不再爆发 它们已经沉寂很久了
Venus, lots of volcanoes there, but they haven't been erupting in a long time, probably.
金星火山也有很多 但可能也很久没喷发过了
And here we have Io, which is just insanely volcanic.
但木卫一 目前正是高潮
It's just pumping out vast amounts of energy in a zone, in a part of
它拥有大量的能源 在太阳系
the solar system where it was thought that everything was dead.
一个认为是毫无活力的地方
Everything we now know about Io comes from looking at it from a distance,
我们对木卫一的了解 都是从远处观察
but measuring the heat pumping out of this lava lake
但测量这个熔岩湖涌出的热量
will give us a better idea of the true scale of the heat loss on Io.
有助于我们计算真正的 木卫一的热损失
Far from being a benign, bubbling cauldron,
老虎不发威 以为是病猫
this volcano has the power to kick off at a moment's notice.
这座火山随时都会证明它的力量
I can just see pieces of molten rock rising up just below my chin,
我才看到熔化的岩石碎片飞到我下巴下方
and with it a cloud of heat, absolutely overpowering heat.
和一片热云 绝对压倒性的热量
There must be a hell... a hell of an eruption going on.
真是个鬼地方...一个喷发的地狱
Seeing active volcanism like this on such a small moon like Io
像木卫一这么小的卫星 却有如此活跃的火山活动
changed our view of the workings of the solar system.
改变了我们对太阳系运作的看法
A world like Io, having such a powerful internal heat source, cries out for an explanation.
它如此强大的内部热源 急需一个合理解释
You see, Io is far too small a world to have retained any internal heat
你看 木卫一这么小个球 不该有
to have the same heat source that powers the Earth's volcanoes.
像地球火山的内部热源的
So something else must be driving that powerful volcanism on Io.
所以肯定是其他什么东西赋予了木卫一力量
New images sent back from recent space probes confirm that Io is a surprising and bizarre world.
最新的图像表明 木卫一实在太过诡异
Being so far from the sun, Io's surface is mostly very cold.
它离太阳很远 表面非常寒冷
It is covered in frozen sulphur, which gives it its yellow colour.
它被冰冻的硫磺覆盖着 因此看上去是黄色的
Yet Io is pockmarked by cauldrons of molten lava.
但木卫一生满了火山"麻子"
You know, I think it is remarkable, and fortunate in a sense,
从某种意义上来说 我们也有幸
that you can come to a place like this on our planet and just
能到达这样一个地方
get the tiniest sense of what it must be like
来体会站在木卫一上
to stand on the edge of one of those magnificent lava lakes on Io.
火山熔岩壮丽的湖泊边的感觉
When we first saw hot volcanic action on Io,
当我们第一次看到木卫一的火山运动
it was quite a surprise for most planetary scientists.
行星科学家们非常惊奇
But by considering simple laws of physics, it didn't surprise everyone.
但考虑到简单的物理规律 没有人感到惊讶
Just weeks before Voyager arrived at Jupiter, three scientists made a prediction,
在旅行者抵达木星的几个星期前 三位科学家作出了预测
and it was one of those predictions that, when you see it, is almost obvious.
现在这些预测看起来是很明显的
It was using physics that had been known for hundreds of years, but nobody had thought of it.
只是运用知道了好几百年的物理知识 但之前谁也没想到过
They predicted that Io should have an intense internal heat source because of its unique position
他们预测 木卫一应该有剧烈的内部热源 由于它在太阳系
in the solar system, very close to a giant planet and surrounded by other large moons.
独特的位置 非常靠近巨大的行星 四周又有其他大型卫星环绕
Io sits about the same distance from Jupiter as our own moon does from Earth,
木卫一与木星的距离大概就是月地距离
but don't forget that orbiting outside Io are its sister moons, Europa and Ganymede.
但不要忘记 木卫一外还有木卫二和木卫三
Io is under the influence not just of the massive gravitational pull
木卫一不仅受到木星巨大的拉力
of Jupiter, but also the additional pull of its neighbouring moons.
同时还受邻近卫星的吸引 (Io魅力无限)
It's this gravitational tug of war that conspires to breathe life into Io.
正是这种引力拔河比赛 导致木卫一今天这样子
Now, Io has a very interesting relationship with Europa and Ganymede,
木卫一与木卫二 木卫三的关系很有趣
because for every four orbits that Io makes around the planet,
木卫一每绕4圈
Europa goes around almost exactly twice
木卫二就绕了几乎整整两圈
and Ganymede goes around just once.
木卫三只绕了一圈
Periodically, they line up together, bang, bang, bang, and Io gets
周期性的三点一线 砰 砰 砰 木卫一获得了
a powerful gravitational kick on a very regular basis.
额外的强大引力 在其基础上
And that has the effect of moving Io out of the nice circular orbit
使得木卫一完美的圆形轨道变成了
into an elliptical or an eccentric orbit.
椭圆形或偏心轨道
Io comes close to Jupiter and then far away from Jupiter, and then close to Jupiter again.
木卫一与木星时远时近 当靠近木星时
And because Jupiter's gravity is so big, that has the effect of stretching and squashing Io.
由于木星强大的引力 木卫一受到拉伸和挤压
Now, imagine it was a squash ball. If you stretch and squash and stretch and squash,
设想它是一个壁球 如果你又捏又搓
then it gets hot by friction, and the same thing happens to this moon.
摩擦就生热 木卫一同理可证
The power of the gravitational interaction between Jupiter and Io is extraordinary.
木卫一与木星之间的引力互动非同反响
It contorts the shape of this tiny moon, moving rock as if it were nothing more than water.
它改变了木卫一的 就像水一样改变了它的外形
Now, this crater is about, what, 30 metres from the base
现在 这个火山口大概是30米高
that you can see down there up to the edge of the rim.
从底部到顶端
Now, Io, when it orbits around Jupiter every 1.8 days,
现在 木卫一 它绕着木星的每1.8天
flexes by something like 100 metres.
就能伸缩到100米
That's three times the height of that crater.
3倍于该火山口的高度
Remember, Io's surface is pretty much like this,
记住 木卫一的表面几乎都是这样
solid rock, so imagine how much energy that takes,
固体岩石 想象下需要多少能源
and all that energy comes from Jupiter's gravitational field,
而所有能量都来自木星巨大的引力
and that is the energy that powers the volcanoes.
这就是火山能量的源头
Io is a world beyond our imagination.
木卫一的世界超乎我们的想象
Its unique gravitational connections
其独特的引力关系
provide a seemingly inexhaustible supply of heat.
提供了看似取之不尽的热量
As well as its huge lava lakes, the heat also powers
其巨大的熔岩湖的热量促使
the largest volcanic eruptions in the solar system.
太阳系最大的火山爆发
Molten rock and gas blasts out from the frigid surface.
熔岩和气浪从寒冷的地面爆炸
The gas expands, shattering lava into a giant fountain of fine particles.
气体膨胀 形成巨大的熔岩喷泉
With weak gravity and a sparse atmosphere,
微弱的重力和稀疏的大气层
Io's volcanic plumes can reach 500 km above the moon's surface.
木卫一的火山喷发可以达到地表500公里以上
This incredible phenomenon, volcanism, comes from the simplest of laws of physics,
这个难以置信的火山活动 只是物理定律最简单的体现
the law that says that heat contained in a planet
法则指出 星球包含的热
must eventually find a way to escape into the coldness of space.
最终需要找到一种方式来宣泄
But what a spectacular way for the laws of physics to play out.
多么壮观的物理定律啊
In the most unexpected of places,
在最意想不到的地方
in the coldest reaches of the solar system,
在太阳系最冷的地方
the laws of physics created a fiery world of wonder,
物理定律创造了一个炽热世界的奇迹
and Io is not alone.
木卫一并不孤单
Many of the hundreds of moons in the solar system
太阳系很多的卫星
are not dead, barren and uninteresting worlds,
并非了无生气
but active, often violent and always beautiful worlds of wonder.
而是活跃的 往往是暴力美的奇观世界
Io is fascinating.
木卫一是迷人的
It doesn't derive its energy from an internal heart source in the same way that the Earth does.
它的内部能量不是起源其本身
It extracts energy from its orbit around its giant parent planet,
而是来自其母行星 木星
Jupiter, and for all those reasons, Io is a wonder of the solar system.
所有的这些原因 使木卫一成为太阳系的奇迹
Our exploration of the planets and moons orbiting our star
我们对行星及其卫星的探索
has given us valuable insights into the nature of our own world.
给了我们宝贵的见解去了解我们自身世界的性质
Our view of the Earth's place in space has been turned on its head.
我们认为 地球已经向太空迈出了第一步
Out there are many truly violent and hostile worlds,
那里有更多真正暴力和陌生的世界
but they're driven by the same laws that shape and control our own world.
但它们以同样的法则形成和控制我们自身的世界
And so, I suppose,
所以 我想
it's in many ways a miracle that we exist at all.
我们真是一个奇迹的存在
Our solar system is like a cosmic laboratory.
太阳系就像宇宙的实验室
Until we went there, we had no idea of what the laws of nature could produce.
没到过 我们都不知道什么自然法则可以奏效
I think one of the most important lessons that our exploration
我认为我们探索太阳系 得到的最重要的经验
of the solar system has taught us is that the laws of nature
就是大自然的规律
can create vastly different worlds with the tiniest of changes.
可以创造出截然不同的世界 即使是最小的变化
We now see how the life and death of planets and moons
我们现在看到的行星和卫星 生存或者死亡
is governed by interconnections which span the solar system,
取决于太阳系的相互关系
and we wouldn't be here if it wasn't for those connections.
没有这些联系 我们也不会在这里