我们为何在此 Why are we here?
我们又来自何方 Where do we come from?
这些问题源远流长 These are the most enduring of questions
而人类天性就爱探索答案 and it's an essential part of human nature to want to find the answers.
追根溯源 And we can trace our ancestry back
时间定格在几十万年前 人类文明出现之刻 hundreds of thousands of years to the dawn of humankind,
实际上 我们的故事将追述至更早的年代 but in reality, our story extends far further back in time.
从宇宙起源说起 Our story starts with the beginning of the universe.
宇宙起源于一百三十七亿年前 It began 13.7 billion years ago.
而今 宇宙中已形成逾千亿星系 And today, it's filled with over a hundred billion galaxies,
每个星系包含数千亿恒星 each containing hundreds of billions of stars.
在这个系列里 我想向大家讲述这故事 In this series, I want to tell that story, because ultimately,
因为说到底 我们也是宇宙的一部分 we're part of the universe,
宇宙即我 我即宇宙 so its story is our story.
若不是有样东西将我们 It's a story that we wouldn't be able to tell,
与浩瀚宇宙紧密地联系在一起 were it not for the one thing
我们便无从讲起这个故事 that connects us vividly to our vast cosmos.
它就是光 Light.
壮丽炫目的宇宙奇迹借由光展现出来 Light reveals the wonders of the universe in all their glory-
犹如千颗太阳般耀眼的恒星 stars that shine with the light of a thousand suns,
巨大的旋涡星系 and vast swirling galaxies.
从没有人类记忆的年代伊始 But light is also a messenger
光就扮演起信使的角色 from a long-forgotten era,
那些来自远方的光 and contained in the light from these faraway places
为我们娓娓道来宇宙起源和演化的故事 is the story of our universe's origin and evolution.
通过光 我们得以 Through light we can stare back
放眼整部宇宙史 across the entire history of the universe
寻根溯源 and discover how it all began,
最终理解光是如何赋予我们生命的 and ultimately see how light breathed life into us.
宇宙的奇迹
信使
这里是埃及卡纳克神庙 This is Karnak Temple in Egypt,
由古代法老建造 built by the ancient pharaohs.
这座宏伟繁复的建筑是向阿蒙神致敬 This vast complex was erected to honour Amun Ra,
阿蒙神即太阳神 是众神之神 god of all gods, god of the sun.
此敬畏之情在一年中 This worship reaches its peak
某短暂的瞬间达到顶峰 during one fleeting moment in the solar calendar,
其持续时间很短 也就一分多钟 an event so brief it lasts for little more than a minute.
建造此庙宇是为了应合 This temple is built to align with
一年一度的天文现象 an astronomical event that happens just once a year-
冬至日的日出 the sunrise at the winter solstice.
"至日"在拉丁文中有"太阳静止"之意 "Solstice" is Latin for "Sun stands still".
因为随着地球绕太阳公转 四季更替 Because as the Earth orbits around the sun and the year passes,
太阳在东方地平线的起点会不断移动 the point at which the sun rises above the eastern horizon moves,
所以在埃及的夏季 太阳从那个方向升起 so here in Egypt in summer, the sun rises over in that direction,
夏过秋来 秋去冬临 and then as summer turns to autumn, turns to winter,
日出点随之移动 而今天 the sunrise point drifts along, until today
正好是12月21日 冬至日早上的六点半 on December 21st, at 6:30 am in mid-winter,
太阳会从庙宇的石柱间升起 the sun rises exactly between the pillars of this temple.
神庙建成的3000多年间 每年的此时此刻 Just once a year, for over 3,000 years,
太阳都将从这两根石柱之间升起 the sun has risen between the two pillars,
将万千光辉洒进神庙 and casts its light into the temple.
这就是来自我们恒星的光线 There it is, the light from our star
像瀑布一样倾泻在这座宏伟的建筑上 cascading down this magnificent structure.
一旦真正感受到此地的历史底蕴 I mean, you can literally feel the history of this place,
便很容易忘记它已有三千五百年历史 so it's easy to forget that this is 3,500 years old,
公元前一千五百年 so in 1500 BC,
地球上最具权势的男人 the most powerful man on the planet,
古埃及法老 the Pharaoh of Egypt,
会于每年的12月21日亲临此地 would have stood here on December 21st every year,
就为了迎接和感受 just to greet and experience
来自阿蒙神的光芒 the light from Amun Ra.
现在我们将详细地了解 This moment that the Egyptians worshipped instinctively
埃及人真心敬畏的这一时刻 we now understand in exquisite detail.
太阳系中的地球绕日公转 As the Earth journeys through the Solar System,
使其充分得到太阳的照耀 it's bathed in the light of the star that sits at its centre.
这些光由太阳表面发出 This light has travelled some 150 million kilometres
经过了一亿五千万公里的长途跋涉 from the surface of the Sun.
在冬至的时候 And at the winter solstice,
光芒洒进了卡纳克神庙 that light pours into the temple at Karnak.
老实说 Well, this building is honestly
这是我见过的最宏伟的建筑 the most magnificent structure I've ever seen.
现在看来 那时的人类根本达不到这样的规模 Now, it's not built on the scale of men.
这完全是一座神之府邸 It's built on the scale of gods, of one god,
太阳之神 阿蒙神的府邸 Amun Ra, the god of the sun.
当太阳沉入地平线 夜幕降临的时候 As the Sun sinks below the horizon and night falls,
宇宙中的无数恒星渐渐进入我们的视野 the whole universe of suns fades into view.
我们不再为太阳建神庙 We no longer build temples to our Sun,
取而代之 我们建造机器 we build machines
它们使我们能够更深地了解宇宙 that allow us to peer deeper into space than ever before,
到达银河中遥远的恒星 甚至更远 to far distant suns out there in the galaxy, and beyond.
在这样的一个夜晚 On a night like this,
肉眼能见的恒星大约有2500颗 there are about 2,500 stars visible to the naked eye,
但是当我们开始建造望远镜而不是神庙时 But when we started building telescopes instead of temples,
数十亿颗恒星映入我们眼帘 we discovered that there are billions more.
我们在夜空中见到的每颗星星 Every star we see in the night sky
都是茫茫银河系中的一颗恒星 is a sun that sits within our own galaxy, the Milky Way.
随着我们逐渐远离 太阳也渐渐暗淡 As we step away, our Sun gradually fades
成为茫茫星海中一个 to become just one dot in a sea of stars.
我们距离美丽的 We now know that we're about halfway out from
银河系中心还有一半的路程 the centre of this beautiful cosmic structure,
即使这些世界与我们有数百万公里之隔 but even though these worlds are many millions of kilometres away,
通过它们发出的光 依旧可以深入了解它们 we know them intimately by their light.
这些光波是纵横于宇宙间的信使 These waves of light are messengers from across the cosmos,
借由它们 我们发现了银河系的奇观 and through them, we've discovered the wonders of our galaxy.
这是礁湖星云 This is the Lagoon Nebula.
从远处看 这团灰尘和气体组成的云状物 From a distance, this cloud of dust and gas
美丽而又平静 appears beautiful and serene.
但这里是个新星的熔炉 But this is a furnace where new stars are forged.
礁湖星云距地球有五千光年之遥 The Lagoon Nebula sits about 5,000 light years from Earth,
肉眼仍能看到的原因 but it can still be seen with the naked eye,
是因为它有一百光年的跨度 because it's 100 light years across,
其中心年轻的高温新星 and brightly lit by the hot,
使得它熠熠生辉 young, new star that sits at its centre,
这颗巨星叫做赫歇尔36 a giant called Herschel 36.
这颗新生恒星的质量是太阳的二十多倍 This newly born star is over 20 times more massive than our sun,
而且燃烧得更猛烈 and burns much hotter,
这使得它表面发出的光呈蓝色 which makes the light that pours from its surface blue.
我们的银河系里还有更大的恒星 And there are even bigger stars in our galaxy.
距离地球七千五百光年处 7,500 light years from Earth
有一颗恒星使得赫歇尔36也相形见绌 is a star that dwarfs even Herschel 36.
它叫做海山二星 Its name is Eta Carinae.
这颗巨无霸星体比太阳重一百多倍 This monster star is over 100 times more massive than our Sun,
亮度更是约为太阳的四百万倍 and burns about four million times brighter,
这使它成为银河系中最明亮的恒星之一 making it one of the most luminous stars in the Milky Way.
一束束光是我们洞察 All we know about these incredible worlds
这些奇妙世界的眼睛 has been brought to us on wave after wave of light.
我们的星系本身就是一首光之交响曲 Our galaxy is a symphony in light.
银河系拥有两千亿颗恒星 The Milky Way is home to 200 billion stars,
但它与宇宙相比也只能是小巫见大巫 but our galaxy is just the beginning.
对与它其中每一颗恒星 For each of these stars,
宇宙中都有数十亿颗与之对应 there are a billion more in the universe beyond.
穿过广袤宇宙 Across the unimaginable reaches of space,
光使我们可以涉足最远的星系 light has allowed us to journey to the most distant galaxies,
目睹恒星的生与死 to see the births and deaths of stars.
不管我们跟随光走了多远 No matter how far we follow the light,
不管我们穿过了多少亿英里 no matter how many billions of miles we cross,
光本身的性质 the nature of light itself
使我们能踏上更丰富的旅程 allows us to go on a much richer journey.
因为无论往上看 往外看 Because to look up, and to look out,
无疑都是在回顾过去 is to look back in time,
那些古老的光束 those ancient beams of light
是遥远过去的信使 are messengers from the distant past,
它们带来了一个故事 and they carry with them a story,
宇宙起源的故事 the story of the origin of the universe.
为了品读这个故事 In order to read this story,
为了明白光如何能把我们带回过去 to see how light can transport us to the past,
首先 我们必须理解它的一条基本性质 we must first understand one of its fundamental properties-
它的速度 its speed.
宇宙中万物都有速度限制 Everything in our universe has a speed limit,
即使是无形的声波和光波 even intangible phenomena like waves of sound and light.
这些速度限制是真正的物理障碍 These speed limits are very real physical barriers,
它们对我们理解宇宙 and they have profound consequences
造成了深远的影响 for our understanding of the universe.
今天 我将尝试打破其中的一个障碍 Today, I'm going to try and break one of those barriers.
这是一架猎人战斗机 This is a Hawker Hunter.
于二十世纪五十年代制造 It was built in the 1950s.
当时打破声障 When breaking the sound barrier
是人类技术能力的极限 was at the very limit of our technical abilities.
声障是个非常有趣的课题 A sound barrier's an incredibly evocative term, you know,
它在航空史上有着近乎传奇般的地位 it has an almost legendary status in the history of aviation,
但是关于它并没有什么基本原则可言 but there's nothing fundamental about it -
用一些极聪明的工程设计 it's something that you can
便可以克服声障 overcome with some extremely clever engineering,
在早期 这还需要很大的勇气 and in the early days, quite a lot of courage.
通常认为 The reason we don't usually think
声音并没有速度限制 about sound as having some kind of speed limit, a limit in speed,
因为与我们在日常生活中习惯的事物相比 is because it is incredibly fast
声音的速度非常之快 compared to the things we're used to in everyday life.
但是今天 我们要尝试打破它 But today, we're going to try and break it.
我将坐上这台不可思议的机器 I'm going to try and break it,
尝试打破它 sat in this marvellous machine.
在地球上 根据海拔高度 声速 On Earth, the speed of sound, depending on altitude
大约是每小时1200公里 也就是1马赫 is around 1,200 kilometres per hour, known as Mach 1.
这架喷气式飞机在普通飞行时速度并不会这么快 This jet isn't designed to fly that fast in normal flight,
但是有种方法可以让它超过声速 but there is a way to make it travel faster than sound,
为此 我们必须飞得很高 and for that, we need to fly high.
真漂亮
我们正以0.85马赫速度飞行（1020公里/每小时）
高度是4.88公里
我们正在飞速爬升
爬升了10.36公里
接近12.19公里
飞机越飞越快 As the plane flies faster,
它开始追上自己的声音 it begins to catch up with its own sound.
声波的速度只是不足以快到甩开飞机 The sound waves simply can't get out of the way fast enough,
所以开始在飞机前面堆积起来 so they begin to pile up at the front of the jet.
但是为了超过声波 But to outrun our sound waves,
我们得努力使这架飞机达到它的绝对极限 we need to push this jet to its absolute limit.
好了 开始急剧下降
无论如何都要下降
翻身也是个好办法
数秒之内 飞机便冲破了声障 In just seconds, the jet smashes through the sound barrier.
在地面上听起来就是一次声爆 This can be heard from the ground as a sonic boom.
我们做到了
干净利落地超过了音速
我们做到了
不得不承认我刚才挺紧张的
真是不可思议
简直不费吹灰之力 It was a doddle, actually.
在12.80公里的高空 Well, you know, having said that, it was inverted full throttle
倒挂金钩 "小菜一碟"可不是这么定义的 at 42,000 feet, but it's a different definition of "Doddle".
这架宏伟的机械大作 So this magnificent piece of engineering
马力十足 只要稍作努力 is fast enough, if you just push it a little bit,
它就能超过自身声音 to outrun its own sound,
所以突破声障不再遥不可及 so the sound barrier is negotiable.
你可以轻易通过 You can smash your way through it.
但光速 也就是光障 But the speed of light, the light barrier,
情况就截然不同了 that's a very different story.
我们能够确切测量声音的速度 Sound has a definite speed that we can measure,
但千百年来 世上的智者们 but for thousands of years, the world's greatest minds
认为光完全是另一回事 thought that light was different,
它的传播是瞬时性的 that it travelled instantaneously from object to eye.
直到大约350年前 Then, around 350 years ago,
凭借一人的聪明才智结合天体有规律的运行 the truth about light was revealed through a combination
光传播的真谛才得以被揭示 of one man's genius and the clockwork orbits of the heavens.
自从伽利略发现了木星的卫星 Ever since Galileo discovered that Jupiter had moons,
天文学家就意识到可以把木星及其卫星 astronomers realised that you could use Jupiter and its moons
当做天空中一轮精准的时钟 as a very precise clock in the sky.
假设这是太阳系 太阳在这 地球在这 So here's the Solar System, there's the Sun, there's the Earth,
而那是木星 这是木星最内环的卫星IO here's Jupiter, and here is Jupiter's innermost moon, IO.
众所周知 IO围绕木星 It was known that IO takes precisely
公转一圈的时间正好是42.5小时 42.5 hours to orbit around Jupiter,
所以 从地球上看来 so if, from the Earth,
如果IO在周二的午夜 you see IO emerge from behind Jupiter at say,
绕过木星进入视野 midnight on a Tuesday,
那么它应该在周四下午六点三十 then you know that it should re-emerge again
再次出现在天际 at 6:30 on Thursday afternoon.
精确 Beautiful.
有位天文学家致力于建立IO环绕木星 Now one of the men charged with making precise tables
公转的准确时间表 of exactly when IO should be seen to emerge from behind Jupiter
他是丹麦的奥尔·罗默 was the Danish astronomer Ole Romer,
但他发现了一丝蹊跷 but he noticed something surprising.
在一年中 See, depending on the time of year,
IO的出现时间 IO emerged later than expected,
总是与预期有或早或晚的偏差 or earlier than expected.
睿智的罗默 Now, Romer's genius was to realise
意识到 that had nothing to do
这与IO环绕木星运行的轨道没有任何关系 at all with the orbit of IO around Jupiter.
产生差距的原因是地球的公转 It was to do with the orbit of the Earth around the Sun.
罗默注意到 See, what Romer noticed was that
如果地球处于 when the Earth was in a position
靠近木星的公转位置上 in its orbit so that it was close to Jupiter,
IO出现的时间就比预期的早 then IO emerged earlier than it was expected to.
随着四季更替 地球公转到 Then, as the year passed and Earth moved around the Sun
远离木星的位置时 and got further away from Jupiter,
IO出现的时间就比预期的晚 Roma noticed that IO then emerged later than it was expected to.
罗默这才发现 光从木星传至地球 Roma realised that it takes time for light to travel from Jupiter
需要花费一定时间 所以当地球远离木星时 to the Earth, so when the Earth is far away from Jupiter,
传播距离大大增长 it takes longer for the light to travel, and therefore
因此IO出现的时间比预期的要晚 you see IO emerge from behind Jupiter later than you'd expect.
然而 当距离较短时 Then, when the distance is small,
光传至地球 it takes less time for the
所用的时间就短 light to travel and you see IO emerge earlier
IO出现的时间就会早于预期 than you might expect.
罗默发现 So Romer had discovered
光的传播不是瞬时性的 that light doesn't travel instantaneously.
它的速度也是有限的 It moves through space with a finite speed.
拜他卓越的洞察力所赐 This remarkable insight
我们开始了对光速的测量 led to a measurement of the speed of light.
现在我们精确地知道 We now know that light travels
光每秒传播299792458米 at precisely 299,792,458 metres per second.
这意味着在我打个响指的瞬间 That means in the time that it takes for me to click my fingers,
光已经绕地球七周 light has travelled around the Earth seven times,
它在一年中的传播距离 or that it travels ten million,
是十万亿公里 million kilometres in one year,
这通常被用作衡量宇宙的尺度 and that's the yardstick that we use to measure the universe,
因为一光年也就约等于 as ten million, because
十万亿公里 million kilometres is approximately one light year.
光速是宇宙的极限速度 The speed of light is the speed limit of the universe
正是它将时间和空间编织成一个整体 built into the very fabric of space and time itself.
但因为光的传播速度有限 But because light travels at a finite speed, a light year
所以光年不只是距离尺度 isn't just a measure of distance,
还是一个时间尺度 it's also a measure of time.
天体的距离越远 The further away an object is,
我们所见之景就越久远 the further back in time we see it.
地球上光传播的距离相对较短 The distances that light travels on Earth are relatively short,
所以它射入人眼的时间几乎难以察觉 so the time it takes light to travel to our eye is imperceptible.
但当我们放眼太空 But when we look out to space,
跨越天文距离 over astronomical distances,
瞭望遥远的恒星 行星和星系 to the stars, planets and galaxies beyond,
有限的光速就会产生深远的影响 then light's finite speed has profound consequences.
这里是位于东非的坦桑尼亚 This is Tanzania in eastern Africa,
孕育人类的摇篮 the cradle of humankind.
二百五十万年前 就在此地 It's here that some of our
我们最早的祖先开始直立行走 earliest ancestors walked 2.5 million years ago.
从古至今 And our evolutionary journey
人类进化的旅程 from the distant past to the present day
与星光的传播一路同行 ran in parallel with the journey of the light from the stars.
太阳距离我们一亿五千万公里 The sun is 150 million kilometres away.
就宇宙的标准而言 这算很接近了 Now, that's very close by cosmic standards,
但光速仅为每小时三十万公里 but light travels at only 300,000 kilometres per second,
也就是说 我们现在看到的太阳是过去的太阳 so that means that we're seeing the sun as it was in the past,
确切地说应该是八分钟前的太阳 actually eight minutes in the past.
如果我们着眼于比太阳更遥远的星球 But when we look beyond our sun to far more distant stars,
我们的跨度甚至 we reach further back in
远远超过了整个人类的进化史 time across the whole of human evolution.
我们看得越深远 And the deeper into space we look,
穿越的时间就越久 the further back in time we see.
待到太阳落山 夜幕降临 As the sun dips below the horizon and night falls,
宇宙渐渐显露眼前 the universe just fades into view,
首先 你会看到耀眼的行星 and at first, you see the bright planets.
我能看到金星 就在那里 I can see Venus over there,
接着 繁星陆续出现 and then the stars appear one by one,
成千上万的星星在夜空中眨着眼睛 thousands of them shining in the sky.
随着夜色越来越浓 银河系现身天际 And then, as it gets darker and darker, the Milky Way appears,
放眼望向银河系的中心 a vast swathe of billions
你将看到不计其数的恒星 and billions of suns as you look out
构成了银河系的中心 towards the centre of our Milky Way galaxy.
但在我看来 But I think, for me,
夜空中肉眼可见的 the most magical thing you can see in the sky
最梦幻的星辰 with the naked eye is just below
莫过于仙后座 the constellation of Cassiopeia,
它的属星排列成W形 the W of stars in the sky.
就在那 There.
确实非常迷人吧 Look at that. Actually, I've got to say that's amazing.
那团模糊的光晕不是一片云 See, that misty patch of light is not a cloud in the sky,
甚至不是我们星系的气体或者灰尘 it's not even gas and dust in our galaxy,
它是另一个星系 that is another galaxy.
叫作仙女座星系 It's the Andromeda galaxy,
它几乎与银河系一样庞大 which is roughly the same size as our own,
是上千亿颗恒星的大本营 an island of hundreds of billions of stars,
位于那个方向上 25 million million million
二百五十万兆公里外的太空 kilometres in that direction.
与银河系相同 Like the Milky Way,
仙女座星系也是个旋涡状星系 Andromeda is a spiral galaxy, two ringed arms
环状的玉臂包围着耀眼的中心 circling a light-filled centre.
仙女座星系的内核里 The core of Andromeda is packed with
满是古老的红星 millions of old red stars.
几乎再没有新星在此诞生 Very few new stars are born here.
相反 在它的漩涡状的玉臂上 In contrast, its spiral arms shine
闪烁着炽热蓝色新星群的光芒 with the light from clusters of hot young blue stars.
这座星光之城发出的耀眼光芒 The light that pours from this stellar city
昭示了人类进化史上的一个重要时刻 connects us to a remarkable time in the story of human evolution.
我刚用相机捕捉到的 The light that I've just captured
这个光点二百五十万年前踏上了旅程 in my camera began its journey 2.5 million years ago.
那时地球上还没有人类 At that time, on Earth, there were no humans.
远古的祖先能人 Homo habilis, our distant ancestors,
正在非洲广袤的平原上漫步 were roaming the plains of Africa,
就是在那些光线 and as those light rays travelled
穿行于无垠宇宙的同时 through the vastness of space,
人类不断进化 our species evolved, and thousands
一代又一代的生老病死 and thousands and thousands of generations of humans lived
周而复始 and died, and then 2.5 million years
旅途开始的二百五十万年后 after their journey began,
这些远道而来的信使 these messengers from the depths of space
穿越漫长的时间 and from way back in our past,
映入现在我们的眼帘 arrived here on Earth,
而我刚刚捕获到它并拍下了照片 and I just captured them and took that picture.
光的速度限制 Light's finite speed opens
让我们得以了解仙女座星系的过去 a window onto the past and shows us Andromeda
看看它在二百五十万年前 as it looked when our early
人类祖先行走去地球时是哪般模样 ancestors walked the Earth 2.5 million years ago.
当我们的观察范围 But by peering further
不再受肉眼限制 than the naked eye will allow, we can journey
我们可以回溯到史前的时间 to a time way before human history,
这是如此之早 以至于我们能纵观 so far back, that we can read
整个宇宙的历史 the entire history of the universe.
在过去二十年里 借助强大的天文望远镜 In the last 20 years, powerful space telescopes have carried us
我们得以涉足前所未有的深空 ever deeper into space,
这使我们成为名副其实的时间旅行者 and we have become virtual time travellers.
这是半人马座A This is Centaurus A,
离我们最近的星系之一 one of our nearest neighbouring galaxies,
只有一千万光年之遥 only ten million light years away.
这意味着这些红色恒星 That means that the light began its journey
以及这些或白或蓝的新星发出的光芒 from these old red, and young white and blue stars,
一千万年前便踏上了旅程 only ten million years ago.
再走得稍微远些 And stepping out a little further,
大约一千四百万光年处 just 14 million light years,
有一个美丽的棒旋星系 there's this beautiful barred spiral galaxy,
同样你可以看到 and again you can see just
许许多多的蓝色新星 lanes and lanes of bright young blue stars,
这些蓝色光芒花了一千四百万年 and this blue light has taken 14 million years to journey
穿过宇宙 映入我的眼帘 across the universe to my eye.
这是NGC520 This is NGC 520,
它是一次宇宙碰撞的产物 and it's the product of a cosmic collision,
但它与我们的距离是一亿光年 but this galaxy is 100 million light years away.
也就是说 That means that the light
当恐龙统治地球之时 began its journey from this galaxy to my eye
这些星光就开始了旅行 when the dinosaurs roamed the Earth.
通过捕捉这些模糊的光 I think it's a beautiful thought
来重塑如此壮观的景象 that by capturing this faint light
想想真是令人愉悦 and rebuilding these spectacular images,
我们与那些遥远星系息息相关 we are in a very real sense connected to these galaxies,
无论它们是如何与我们天各一方 no matter how far away they are across the universe,
那些经过数十亿年旅行到达地球的光线 connected by the light
终究会把我们联系在一起 that's journeyed billions of years to reach us.
但这些辽阔壮观的星系 But these spectacular galaxies
并非我们这场追溯之旅的尽头 are not the end of our journey into the past.
在2004年 我们观测到了更久远的过去 In 2004, we peered further back in time than ever before,
并且捕捉到了来自 and captured the light from
宇宙最远处星系的光线 the most distant galaxies in the universe.
这个影像叫做哈勃超深空 The image is called the Hubble Ultra Deep Field.
这是由哈勃太空望远镜 It's a picture taken by the Hubble Space Telescope
历时十一天 over a period of eleven days
聚焦猎户星座下方那最小的一片天空 and it focused its camera on the tiniest piece of sky
而拍到的一张照片 just below the constellation of Orion.
现在 如果你伸出拇指 Now, it's a piece of sky that you'd cover if you took your thumb,
然后向外平移20倍的距离 held in front of your face
这片天空就能被它遮住 and then moved it 20 times further away.
但是哈勃捕捉到了 But the Hubble captured the faintest
来自最遥远宇宙最微弱的光线 lights from the most distant regions of the universe,
然后拍下了这张照片 and it took this photograph.
图像上所有光点都并非恒星 Now, almost every point of light in that image is not a star,
而是几千亿恒星组成的一个星系 but a galaxy of over a hundred billion stars.
这幅图像上最遥远的星系 The most distant galaxies in
与我们有130多亿光年之隔 that image are over 13 billion light years away.
也就是说来自那些星系的微弱光线 That means that the faint light
在130亿年前 from those galaxies began its journey
便踏上了奔向地球的旅程 to Earth 13 billion years ago.
那可是地球寿命的三倍还多 That's over three times the age of the Earth.
哈勃望远镜使得我们几乎能够 Hubble allows us to peer back
追溯到时间的起点 almost to the beginning of time itself,
在这里 在深空里 and out here, in deep space,
它揭示了宇宙起源的线索 it reveals a clue to how our universe began.
当太空望远镜的目光穿透宇宙时 When the space telescope stared across the cosmos,
五颜六色的星系尽收眼底 it saw galaxies glow in all different colours.
但当达到观测宇宙可视范围内边际时 But when it peered to the very edge of the visible universe,
它捕捉到了这些图像 it captured these images...
看到每个星系都发着红光 ..And saw that every galaxy glowed red.
这些来自遥远世界的红光 Written in the red light from these distant worlds
记载着宇宙起源和演化的故事 is the story of our universe's origin and evolution.
为了揭开谜团 我们必须探索一下 To reveal it, we must explore
光最为美妙的特性之一 one of the most beautiful qualities of light.
几个世纪以来 人们 For centuries, people
一直认为光只是世界的明灯 thought that light just illuminated our world,
让我们看见万物 除此之外别无它用 allowed us to see, and nothing more than that.
但我们后来才知道每一光束中 But we've since learnt that there is a vast amount
都包含着大量的信息和详情 of information and detail contained within every beam of light.
而这信息的载体就是颜色 And that information is written in colour.
为了说明颜色是如何 To reveal how colour can
揭示我们宇宙巨作的秘密 unlock the secrets of our universe's creation,
我来到了地球上 I've come to one of the
最为壮观的自然奇观地之一 most spectacular natural wonders on Earth.
这里是赞比亚的维多利亚瀑布 This is Victoria Falls in Zambia.
这个瀑布纵伸近两千米 This waterfall stretches for almost two kilometres,
使它成为了世界上最大的"水帘" making it the largest curtain of falling water in the world.
但我不是来赞叹这宏伟的自然奇观的 But I'm not here to marvel at the scale of this wonder-
我来这里是要看这水面上 I've come to see a much more delicate feature that appears
一个更为美妙的现象 above the water.
这些壮丽的彩虹 These magnificent rainbows
永久的定格在维多利亚瀑布的上空 are a permanent feature in the skies above Victoria Falls.
彩虹是一种美丽的现象 Now, rainbows are a beautiful phenomenon,
但我认为当你明白它们的形成过程后 but I think that they're even more beautiful
你会觉得它更加美丽 when you understand how they're made,
因为它们直观展现了 because they are a visual representation of the fact
光所包含的七种颜色 正是彩虹的七种颜色 that light is made up of... well, all the colours of the rainbow.
太阳光在射入水滴时会发生弯曲 Rays of light from the Sun bend as they enter the water droplets,
光束随后在水滴另一面被反射回来 the light beams then reflect off the back of the droplets,
当它们离开水滴时再次弯曲 and are bent for a second time, as they leave.
这样的弯曲和反射将光线分散 This bending and reflecting splits the light
隐藏在白色阳光内的颜色就呈现出来了 and the colours hidden inside the white sunlight are revealed.
但颜色告诉我们的远不止如此 But colour can tell us much more,
因为对于红化星系的了解 because understanding the reddening of the galaxies
使我们对宇宙本质的有了更深入的见解 has given us a profound insight into the nature of the universe.
看上去不同的色光 What we see as different colours
其实上是波长不同的光线 are actually different wavelengths of light.
所以蓝光的波长相对较短 So blue light has a relatively short wavelength,
其次是绿光 黄光 and then you go through green and yellow,
最后是光谱末端上的红光 all the way to the red end of the spectrum,
红光的波长很长 which has a very large wavelength.
星光是由无数不同波长的光组成的 Starlight is made up of countless different wavelengths,
包含有彩虹中的色光 all the colours of the rainbow.
当光从遥远的恒星或星系发射出来 When light is emitted by a distant star or galaxy, its wavelength
它的波长并不一定保持不变 doesn't have to stay fixed,
它可以被压缩也可以被拉伸 it can be squashed or stretched,
当光被拉伸 它的波长就会变长 and when light's stretched, its wavelength increases and it moves
并向光谱的红端靠近 to the red end of the spectrum.
所以对于最遥远的星系 So the interpretation of the fact that
呈现红色的解释就是 the most distant galaxies appear red is that
当光线自远方传向我们的同时 the space in between them and us has stretched
彼此之间的空间拉伸了 during the time it's taken the light to journey over that vast distance.
这就意味着整个宇宙正在不断膨胀 That means that our entire universe is expanding.
现在 想一下这个膨胀的宇宙暗示了什么 Now, just think about what an expanding universe implies,
因为如果星系在迅速地彼此远离 because if the galaxies are all rushing away from each other,
那就是说如果时间倒退 that means that if you rewind time,
那么过去它们 then they must have been
一定靠得更近 而事实上 closer together in the past, and actually,
如果让时间不停倒退 那么你会发现 if you just keep rewinding, then you find that at some point
在过去某时间点 宇宙中所有可见星系 in the past, all the galaxies we can see in the sky
其实是互相重叠的 were quite literally on top of each other.
整个宇宙被压缩成了一点 The universe was squashed down to a point.
这意味着宇宙或许是有开端的 That implies that the universe may have had a beginning,
这就是宇宙大爆炸理论 and that is the Big Bang Theory.
这可能就是许多人 Well, that's probably many
脑海中大爆炸的图片 people's picture of the Big Bang, you know,
物质被迅速的抛向四周 this vast explosion that flung matter out into the void,
但那是完全错误的 but that's completely wrong.
我们现在的理解是 As we understand it at the moment,
所有空间在那一瞬间诞生 all of space was created at that moment.
所以大爆炸并不是只发生在那里 So the Big Bang didn't just happen somewhere out over there in the universe,
它同时发生于任何地方 it happened everywhere at the same time.
它发生在这里 It happened here.
所以这一片空间就在发生大爆炸 So this space here was at the Big Bang.
所以当我们抬头眺望遥远的星系时 So when we look at the distant
我们发现它们正迅速远离我们 galaxies and we see that they're flying away from us,
这不是因为它们在时间初开的时候 that's not because they were flung
被剧烈的爆炸甩了出去 out in some massive explosion at the beginning of time.
而是因为宇宙空间本身在扩张 It's because space itself is stretching,
这种扩张从大爆炸就开始了 and it's been stretching since the Big Bang.
我们今天看到的宇宙是各个星系交织而成的网络 The universe we see today is a network of galaxies
它们的跨度有近1000亿光年 spanning almost a hundred billion light years.
但值得关注的是 这惊人结构的蓝图 But remarkably, the blueprint for this astonishing structure
早已记录于宇宙中第一道光线中 is written into the very first light released into the universe.
更值得关注的是 Even more remarkably,
时至今日 我们仍能拜读这幅蓝图 it's a blueprint that we can read today.
这第一束光已经在视野中消失 但它依然存在 This first light is no longer visible, but it's there.
你只需要知道如何寻找它 You just need to know how to look for it.
这片流砂海是纳米布沙漠 This sea of shifting sand is the Namib Desert,
世界上最古老的沙漠 the oldest desert in the world,
当风扬起丘顶的沙粒 and, as the wind blows the sand off the top of the dunes,
这片地貌就会不断发生改变 this landscape is constantly changing.
太阳塑造了这片世界 This world has been sculpted by the Sun.
它驱使风为沙丘塑形 It drives the winds that shape the dunes,
而它的光也将这里染成了深橘色 and its light paints this place a deep orange.
但即便太阳完全消失 But even when the Sun disappears completely
这片沙漠也会继续书写 this desert is still awash
光和色的篇章 只是我们看不到而已 with light and colour, we just can't see it.
可见波长的光 Visible wavelengths of light
只是宇宙所有光中很小的一部分 are just a tiny fraction of all the light in the universe.
在可见光光谱之外 Beyond the visible spectrum,
我们的世界被不可见光照耀着 our world is illuminated by invisible light.
这些沙粒整天被阳光炙烤 This sand has been under the full glare
我可以感觉到热量从里面散发出来 of the sun all day and I can feel the heat radiating off it.
热量只不过是光的一种形式 Well, heat is nothing more than a form of light,
尽管我们通常不这样称呼 although we don't normally call it light.
它事实上是红外线 It's actually infrared light,
它和可见光的唯一区别就是波长 and the only difference between infrared and visible light is the wavelength.
红外线的波长比可见光长 Infrared has a longer wavelength than visible light.
红外线并非故事的尽头 Infrared isn't the end of the story.
还有比它波长更长的光 There are even longer wavelengths of light.
在人类历史上 Throughout most of human history we've
我们对这些陌生的光并不了解 been blind to these more unfamiliar forms of light,
但要检测到它们 不需要价值不菲的卫星 but to detect them you don't need a billion-pound satellite
或是建在山中的望远镜 or a telescope built into the side of a mountain,
你只需要 you just need
这个 一台收音机 因为... one of these, a radio, because...
当我们在调收音机时 When we tune a radio,
我们是在收听光的一种形式 无线电波 we're tuning in to a form of light, radio waves.
但是检测并认识它们 But detecting them and understanding them
对于理解宇宙的起源至关重要 provides the key to understanding the origin of the universe.
而当你微调一下就只能听见静电噪音 And when you detune the radio a bit you can just hear static,
但约有1%的静电噪音 but about 1% of that static
在物理学家听来是优美的音乐 is music to the ears of a physicist,
因为那是大爆炸中被拉伸的光 because that is stretched light from the Big Bang.
所以这个声音就是 So that sound is the sound of the
宇宙起源时释放的第一束光奏响的乐章 first light released at the beginning of the universe.
将他安全带回来 Carry him home safely to me...
我们看不见远古的光是因为 随着宇宙膨胀 The reason we can't see this ancient light is because, as the universe expanded,
光波被拉长 the light waves were stretched
从而变为无线电波和微波 and transformed into radio waves and microwaves.
这第一束光被叫做 This first light is called
宇宙微波背景 简称CMB the Cosmic Microwave Background, or CMB.
CMB充斥着宇宙的每个角落 The CMB fills every part of the universe.
每一秒钟 来自时间起点的光线 Every second, light from the beginning of time is
都在如暴雨般无休止地落在地球表面 raining down on the surface of the Earth in a ceaseless torrent.
要是我能看到的话 If my eyes could only see it,
天空将因这原始的光线而灿烂闪耀 then the sky would be ablaze with this primordial light,
无论白昼黑夜 both day and night.
在130多亿年的时间里 These waves have been
这些波一刻不停的驶向我们 travelling towards us for over 13 billion years.
它们是信使 They are messengers,
带来宇宙起源的信息 carrying information about the origin of our universe.
2001年 一枚名为WMAP的卫星 In 2001, a satellite called W Map took a
全称 Wilkinson Microwave Anisotropy Probe
拍摄了一张天空的全景微波图 photograph of our entire sky
以捕捉那束古老的光线 to capture this ancient light.
这张图像显示了大爆炸后 The image reveals that the blueprint of
整个宇宙诞生 the entire universe was created moments
瞬间的结构蓝图 after the Big Bang.
这是科学史上一幅最为重要的 Well, this is one of the most important
天空全景图 images of the sky ever taken in the history of science.
也许它并不如涡旋星系或是星云那样美丽 It doesn't have the beauty of a spiral galaxy or a nebula
但对于科学家 尤其是宇宙学家而言 but to a scientist, to a cosmologist,
它就是最美丽的图片 it is the most beautiful picture ever taken,
因为这张图片包含了 because it contains a vast amount of
大量宇宙诞生伊始的信息 information about the very earliest history of our universe.
第一次宇宙微波背景的探测结果 When the CMB was first detected, it appeared
说明宇宙是各向同性的 that the universe was exactly the same in all directions.
可是WMAP卫星却向我们揭示了 But W Map shows us that the early universe
宇宙并非如此整齐划一 was far from uniform.
有些区域密度更大 Some areas were denser than others,
正是这些波纹 and it's these ripples
为宇宙中的星系结构奠下基础 that seeded all the structure in the cosmos.
对于宇宙微波背景中 The explanation for those
这些波纹的解释非常惊人 ripples in the CMB is absolutely mind blowing,
人们认为它们发端于 because it's thought that they originated
宇宙诞生之时 in the first billion-billion-billion-
几千亿分之一秒内 billionths of a second after the universe began,
那时在可观范围内的宇宙 when the whole observable universe
尚比一粒沙子更为渺小 was billions of times smaller than a grain of sand
而一丁点小小的起伏 and little fluctuations called quantum
称为量子起伏（量子涨落） fluctuations made little bits of
使得宇宙的一部分密度更大了 the universe a bit denser.
随着宇宙不断膨胀 Those dense regions then got
这些稠密的区域密度也继续增长 denser and denser as the universe continued to expand
为第一颗恒星 第一个星系 and they seeded the formation of the
播下发芽生长的种子 first stars and the first galaxies in the universe.
最原始的宇宙是物质与辐射的海洋 The early universe was a hot,
它十分炽热 几乎整齐一致 almost uniform, sea of matter and radiation.
随着宇宙的膨胀 As the universe expanded,
原先只是轻微密集的区域变得极度稠密 the slightly denser regions became increasingly dense.
原子簇集在一起形成了最原始的结构体 Atoms clumped together to form the first structures.
时光荏苒 这些结构体 Over time these structures grew so
发育得异常庞大 massive that they collapsed
并因为自身重力开始塌缩 under their own gravity.
氢原子融合在一起 释放出巨大的能量 Hydrogen fused, releasing enormous amounts of energy.
宇宙大爆炸的两亿年后 200 million years after the Big Bang,
第一颗恒星横空出世 the first stars in the cosmos burst into life.
黑暗被无情的撕碎 Darkness was banished
从此宇宙开始沐浴光明 and the cosmos began to fill with light.
一颗颗行星闪亮登场 Planets formed and fell into orbit around
围绕着恒星运转 the stars and these young
而这些年轻的太阳系则围绕着星系运行 solar systems orbited the galaxies.
而这一切存在的原由 And the only reason why any of this
都是因为宇宙在诞生之初 exists is because of those tiny density fluctuations
尚如沙粒大小时 that appeared when the observable
就包含的微小的量子起伏 universe was smaller than a grain of sand.
没有它们 就没有行星恒星 Without them there would be no planets
更没有星系一说了 or stars and no galaxies.
我们的宇宙将在各个方向丝毫不差 Our universe would look the same in every direction.
亿万年过去了 For billions of years,
无数恒星交替诞生或消亡 generations of stars lived and died.
于是 大爆炸后的第九十亿年 And then, nine billion years after it all began,
在英仙臂的猎户臂处 in an unremarkable piece of space in the
一片不起眼的空间 Orion spur of the Persius arm of
也就是我们的银河系 a galaxy called the Milky Way,
一颗恒星诞生了 那就是太阳 a star was born that we call the Sun,
她照亮了我们萌芽中的太阳系 that illuminated our embryonic Solar System with light.
使我们沐浴在和煦温暖的 So the light from the star
光芒之中的恒星之光 也在宇宙诞生 that bathes the Earth has its ultimate origin
那一瞬间的微小波纹中 in the tiny ripples that appeared
拥有自己最初的归宿 in the first moments of our universe's life.
通过捕捉天空中的光芒 By capturing the light from the skies,
我们可以发掘出 we've been able to tell the
宇宙的起源与演化 story of the universe's origins and evolution,
这么伟大的一件事 and it's worth reflecting on
绝对值得回味 what a remarkable thing that is.
像我一样的沧海一粟 You know, little beings like me
匆匆行走与一块岩石表面 scurrying around on the surface of a rock
而这块岩石不过是某个星系边缘的一处角落 on the edge of one of the galaxies
尽管如此 我却能够 have been able to understand
一窥宇宙起源与演化的奥秘 the very origin and evolution of the universe.
但是这个故事中还有另一个转折点 But there's one more twist to this story,
因为这种利用光线 because that ability to use light,
捕捉它 透过它来了解世界的能力 to capture it, and use it to understand our world,
对于地球上 may have played a key role
复杂生物的出现可能至关重要 in the emergence of complex life on Earth.
这里是优鹤国家公园 This is the Yoho National Park
坐落于加拿大落基山脉 in the Rocky Mountains of Canada,
它是北美洲最为壮观的 one of the most spectacular mountain ranges
山脉之一 in North America.
一百年前 在布尔吉斯页岩上 100 years ago, a fossil
人们发现了一片化石场 field was discovered here at the Burgess Shale
那里可能揭示了光线 that may reveal how light
是如何打造地球生命的 shaped life on Earth.
这是世界上最重要的 Well, this is one of the
化石发现地之一 most important fossil sites in the world,
事实上它也是 but actually it's one of the
最为重要的科学研究场所之一 most important scientific sites of any kind,
不仅仅是因为封存在这些岩石中的 and it's not just because of the number
动物数量奇大 and diversity of animals
种类繁多 you find fossilised in these rocks,
更因为它们着实历史悠久 it's because of their age.
这些化石已经有五亿年的历史了 These fossils are over 500 million years old.
地球上几乎没有比它们更早的 There is virtually no record
复杂生物记录了 of complex life on Earth before this time.
似乎是一刹那间 It's as if, at one instant
在寒武纪时代的某一瞬间 in this time we call the Cambrian Era,
一种复杂的多细胞生命 complex multi-cellular life
突然完好无损地出现在星球上 suddenly emerged almost intact on the planet.
这一事件被称为进化大爆炸 It's called the Evolutionary Big Bang.
这是在化石层里找到的 This is one of the beautiful
一种非常美丽的动物 animals you find up here in the fossil beds.
它叫三叶虫 是一种很复杂的生物体 It's called a trilobite. It's a very complex organism.
有外骨骼 有肢臂关节 It's got an external skeleton, it's got jointed limbs,
但是 最为引人注目的 but, perhaps most remarkably,
恐怕就是这些复眼了 these, because these are compound eyes.
它们已经发育得非常精密 They were very sophisticated
它是最早出现的一类掠食者 and this was one of the first predators
可以探测到物体形状 捕捉到移动状态 to be able to detect shapes and see movement
还可以成功捕食猎物 and it could successfully chase its prey.
这些生物是第一批 These creatures were among the first
利用起宇宙光芒的生命 to harness the light that filled the universe.
在它们出现之前 日升日落 Before they emerged, the rise and fall of the Sun
满天星辰 无人关注无人问津 and the stars in the night sky simply went unnoticed.
现在有一种理论推测 Now, there is a speculative theory
正是眼睛的出现 that the emergence of the eye
引发了寒武纪大爆炸 actually triggered the Cambrian Explosion,
即进化大爆炸 this evolutionary Big Bang,
因为一旦有一种物种有了眼睛 because, once one species got eyes,
其它物种也会被迫进化出眼睛 then other species had also to develop eyes
或是作为猎食者捕食它们 to either chase them as predators
亦或作为猎物躲避追逐 or evade them as prey,
于是就引发了进化上的军备竞赛 and that led to an evolutionary arms race.
更多的复杂生物得以进化成形 More and more complex life forms developed.
所以 眼睛的进化 So the evolution of the eye
很有可能在地球复杂生命的诞生过程中 may have played a fundamental role
起到至关重要的作用 in the emergence of complex life on Earth...
也有可能引发了人类这一物种的进化 ..and could have led to the evolution of our species.
看到这个小东西了吗 尽管毫不起眼 See, this little thing, although it looks unimpressive,
却可能是目前为止我们 may be the most important
进化史上发现的最为重要的动物 animal that we've ever discovered in our history.
它叫皮卡虫 是一种小型蠕虫状的生物 It's called a Pikaia and it's a little wormlike creature
不过它的发现可是一个重要纪元 but it's thought that this is a core date,
而且与我们处于同一生物分支 and that is the branch of life that we're in,
因此它可能是我们已知的最早的祖先 so it could that this is our earliest known ancestor.
更为吸引人的是 人们认为它 What's also fascinating is it's also thought that this
可能具有感光能力 may have been able to detect light,
它可能拥有原始的 it may have had primitive cells
光敏细胞 that were sensitive to light,
使得它至少从某种意义上说可以看到光 and allowed it in a very loose sense to see.
如果这是真的 But if that's true then
那么这个小家伙可能就是我们的直系祖先 this little guy may be our direct ancestor
而这些小小的细胞 and those little cells may be
可能在千百万年的进化中 the things that evolved,
逐渐发育完善 over hundreds of millions of years,
并最终存在于我们眼中 into our eyes.
没有皮卡虫 我们可能永远无法 Without Pikaia we may never have evolved
进化出这样挖掘事实发现奥秘的能力 and developed the ability to see how this story unfolded.
了解宇宙的过程就像一部侦探小说 Understanding the universe is like a detective story
细碎的证据通过 and the evidence has been carried
穿越无垠的宇宙的光线传递给我们 to us across vast expanses of space by light.
我们已经可以捕捉到 We've even been able to
时间起点的那束最原始的光线 capture the light from the beginning of time
我们也已瞥见自身起源的萌芽与开端 and we've glimpsed in it the seeds of our own origins.
随我而来 你会身处 Come with me, and you'll be
一个充满幻想的世界 in a world of pure imagination
轻瞥一眼 你会坠入 Take a look and you'll see
一弯自我的狂想之中 into your imagination...
我们更看到了我们祖先 And we've seen things
可能无法相信的事实 our ancestors wouldn't believe.
恒星在遥远的国度浴火重生 Stars being born in distant realms.
异星世界伴随着重力塌缩重建 Alien worlds created by gravity.
而波澜壮阔的星系则在时间中凝固成永恒 And spectacular galaxies frozen in time.
可是我们不仅仅是这些事件的见证者 But we're not mere witnesses to these events...
因为宇宙的故事 就是我们的故事 ..Because the story of the universe is our story.
我们了解了星尘 We've learned how the dust
如何创造了我们彼此 of the stars makes each and every one of us,
一个简单的宇宙化学体系 how a simple universal chemistry set
如何描绘出了我们今天所看到的一切 makes everything we see.
我们探索深度时间 We've explored how the secrets
如何打造宇宙尽头的奥秘 of deep time shape the destiny of the universe
更为生命存在的 and marvelled at the brief
那短暂一瞬而叹为观止 flickering moment in which life can exist,
我们还看到了星尘如何 and we've seen how stardust falls
建造出宇宙中最宏伟的结构体 to build the grandest structures in the universe.
我们知道这一切 We know all this because of
都是因为光束为我们传递来了信息 messages carried on beams of light.
这是一件多么神奇的事情 And isn't it a wonderful thing
那些早在五亿年前 that these biological light detectors
寒武纪时期就出现的 that first emerged half a
探测光线的生物结构 billion years ago in the Cambrian Explosion
最终进化成了现在的人类 have evolved into those most human of things,
我们所拥有的 绿色 蓝色 our green, blue and brown
棕色的双眸 使我们可以凝望夜空 eyes that are able to gaze up into the night sky,
俘获那些遥远的恒星所散发的光芒 capture the light from distant
读懂这个宇宙的故事 stars and read the story of the universe.
随我而来 你会看见 Come with me, and you'll be
一个充满幻想的世界 in a world of pure imagination
轻瞥一眼 你会坠入 Take a look and you'll see
一弯自我的狂想之中 into your imagination
在我的乌托邦中徜徉... Travelling in a world of my creation...