恒星既大且热, 无处不在 Stars, they're big, they're hot, and they are everywhere.
恒星主宰宇宙 Stars rule the universe.
我们的命运跟恒星的紧密相连 Our destiny is linked to the destiny of stars.
诞生于狂暴, 于猛烈爆炸徐徐消亡 Born in violence, dying in epic explosions.
它们令宇宙满布星尘, 生命的构块 they fill the universe with stardust, the building blocks of life.
人体每个原子 Every atom in your body
都来自恒星的狂暴核心 was produced inside the fiery core of a star.
恒星使宇宙畅顺运作 Stars are what make our universe work.
万物皆始于此 All life begins here.
解读宇宙 How the Universe Works
第1季第4集：恒星 Stars
夜空繁星闪闪 The night sky is packed with stars.
在郊区的明净夜空 On a clear night in the country,
幸运的话 能看到3000颗星星 if you're lucky, you could see maybe 3,000 stars,
但原来那只是浩瀚冰山的小小一角 but that's just the tip of a vast cosmic iceberg.
单在我们银河系就有逾1000亿颗星 In our galaxy alone, there are over 100 billion stars,
事实上, 在能观察到的宇宙里 and in fact there are over 100 billion galaxies
就有逾1000亿个银河系 in the observable universe.
恒星的数量远较地球的沙粒多 There are more stars than there are specks of sand on Earth,
每颗恒星都威力强大 Every star is powerful,
创造出组成宇宙万物的基本物质 creating the basic matter for everything in the universe,
包括我们 including us.
大多恒星远离地球, 我们所知不多 Most are so far away, we know little about them.
但有一颗恒星很接近我们 But there is one star that's really close,
我们对恒星的认识就从这邻居而来 and virtually everything we know about stars we've learned from that neighbour.
每天照耀、温暖我们的阳光 The sunlight from our sun that bathes us and warms us every day
其实只是星光 is nothing but starlight,
因太阳跟同类一样, 都只是恒星 because our sun is nothing but a star, like all the rest
从地球看去, 太阳是极耀眼的光球 Seen from Earth, our sun is a blinding ball of light,
但撇开耀眼强光 but take away the glare
宇宙里其一极具威力的物体 and one of the most powerful objects in the universe
就出现在我们的后院 appears in our own backyard.
这是一个过热气体球 It's a ball of superheated gas
照亮我们的太阳系已46亿年 that's been lighting our solar system for 4.6 billion years
并主宰地球万物 and dominates all life on Earth,
太阳离地球9300万英里 The sun is 93 million miles away
非常遥远 and that means in actuality it's immense.
太阳能容纳100万个地球 You could fit a million Earths inside the sun.
太阳直径接近100万英里 It's nearly a million miles in diameter,
但跟巨型恒星相比, 太阳很渺小 yet our sun is tiny compared to the really big stars out there.
船底座伊塔星比太阳大逾500万倍 Eta Carinae, over five million times larger than our sun.
参宿四则较船底座伊塔星大300倍 Betelgeuse, 300 times larger than Eta Carinae.
若那是我们的太阳 If it was our sun,
就会去到木星那么远 it would reach as far out as Jupiter.
还有极庞大的大犬座VY And then there's this monster, VY Can is Major is,
至今发现最大的恒星 the largest star ever discovered,
比我们的太阳大10亿倍 a billion times bigger than our sun.
恒星以不同颜色燃烧 Stars burn in different colours,
红色、黄色、蓝色 from red, to yellow, to blue.
有些独自存在 Some live alone,
有的成双成对, 围绕对方运行 others in pairs orbiting each other,
并结合成为巨型银河系 and coming together in huge galaxies,
由数以十亿计恒星形成的城市 entire cities made up of billions of stars.
每颗恒星都独一无二 Each star is a one of a kind,
但全部以相同方式展开生命 but they all start life in the same way,
开始时是尘和气体组成的云: 星云 as clouds of dust and gas called nebulas.
直径达数十亿英里 Many billions of miles across,
它们漂流于太空, 形成夺目的形状 they drift through space forming spectacular shapes.
火焰星云 The Flame Nebula.
马头星云 The Horsehead Nebula.
猎户座星云 The Orion Nebula.
每个星云都是恒星哺育室 Each nebula is a star nursery,
数以百万计新恒星就在那里诞生 where millions of new stars are being born.
但诞生过程十分隐密 But this birth is hidden from view.
星云中一些更戏剧性的部分 Some of the more dramatic parts of a nebula
并不是你看到的漂亮发光气体 are not the beautiful glowing gas that you see,
而是黑漆漆的部分 but the dark parts.
黑暗部分… The dark parts have areas...
有稠密的气体和尘 of dense gas and dust,
那就是恒星形成过程中的 and that's where the real action is happening
风起云涌之处 in terms of star formation.
尘云极厚, 普通望远镜无法看透 The dust clouds are so thick, regular telescopes can't see inside.
没甚么比恒星对我们更重要 There's nothing more important to us than stars,
但一直以来, 恒星形成过程是个谜 but for a long time, the way they formed was a complete mystery.
我们无法观察得到 We couldn't observe them.
试想像 Imagine that,
我们无法看到恒星诞生之初的情况 we could not see the first moments of a star at all.
直到2004年 Until 2004,
太空总署发射斯皮策空间望远镜 when NASA launched the Spitzer Space Telescope.
发射 And liftoff,
找寻我们宇宙进化的奥秘 seeking hidden secrets in the evolution of our universe.
斯皮策空间望远镜是个红外线望远镜 Spitzer is an infrared telescope.
只看到热力 It only sees heat
热力穿透星云厚厚的云尘 Heat passes through the thick dust of the nebulas,
让斯皮策看到在里面形成的新恒星 allowing Spitzer to see new stars coming to life inside.
这些照片捕捉到恒星初诞生的时刻 These remarkable pictures capture the earliest moments in a star's life,
一团团氢气开始变热 as pockets of hydrogen gas begin to heat up.
所有气体和尘都发光 Any little bit of gas and dust is glowing.
本来漆黑一片的地区变得明亮 Areas that were entirely dark now became bright
我们能看到恒星形成的最初阶段 We can actually see the very earliest parts of star formation.
制造恒星只需要氢气、重力和时间 All you need to make a star is hydrogen, gravity and time.
重力把尘和气体拉入一个巨型旋涡 Gravity pulls the dust and gas into a giant, swirling vortex.
重力把物质拉在一起 Gravity brings matter together,
把物质拉在一起 and when you bring matter together
然后塞进细小空间里 and you squeeze things into smaller spaces,
它们必会加热 they necessarily heat up.
这是简单的化学原理 It's a simple law of chemistry:
压缩东西就会迫使温度上升 you compress something, you drive the temperature up.
经过几十万年 Over hundreds of thousands of years,
星云越来越厚, 形成巨型旋转盘 the cloud gets thicker and forms a giant spinning disc
比我们整个太阳系还要大 bigger than our entire solar system.
中心的重力把气体… At its centre, gravity crushes the gas
挤压成超稠密、超热的球体 into a super-dense, super-hot ball
压力积聚, 直至气体从中心喷出来 Pressure builds until huge jets of gas burst out from the centre.
恒星形成的过程就是这么狂暴 That really shows you how violent a process star formation is.
这些喷射流的直径达许多光年 These jets are many light years across.
有东西令物质迅速加速 Something is literally accelerating material very fast
飞越想象不到的距离 across unimaginable distances.
重力令压力持续 Gravity keeps the pressure on,
吸入气体和尘粒, 使它们相撞 sucking in gas and dust particles that smash into each other,
产生更多热力 generating more and more heat
其后50万年 Over the next half a million years,
年轻恒星变得更小、更明亮及更热 the young star gets smaller, brighter and hotter.
它的核心温度高达1500万度 tempreture at its core, reach 15 million degrees.
就只有在如此高温 Only at that mind-boggling temperature
气体原子才能开始熔合 can atoms of gas begin to fuse together,
释放大量能量 releasing massive amounts of energy.
就是这样, 一颗恒星诞生了 And just like that, a star is born.
它会发亮几百万、几十亿… It will shine for millions, even billions,
以至几万亿年 or perhaps even trillions of years.
恒星产生大量热和光, 达数十亿年 Stars produce massive amounts of heat and light over billions of years.
但那需要极大量燃料 But that takes fuel, and lots of it
20世纪初以前, 没人知道燃料是啥 Until the early 20th century, no one had any idea what this fuel was.
上世纪初, 物理学面对最大的问题 The greatest problem facing physics at the turn of the last century
是: 恒星的能量源自甚么? was what drives the energy of stars.
其实你只需要往外面看看 All you had to do was look outside
就会明白人类的知识存在一个漏洞 and realise there was a huge gaping hole in our understanding.
为解开恒星的秘密 To solve the secret of the stars,
我们需要一个新引掣 we needed a new engine,
需要极厉害的能量来源 we needed a fabulous source of energy
足以驱动恒星几十亿年 that could drive a star for billions of years at a time.
结果由一位天才发现了: 爱因斯坦 And it took a genius to discover it, Albert Einstein.
其理论证实恒星能开发原子里能量 His theories proved that stars could tap into the energy inside atoms.
恒星的秘密就是爱因斯坦的方程式 The secret of the stars is Einstein's equation:
E=mc2 E=mc2
从某层面看, 组成人体的物质 In some sense, matter, which makes up our body.
是聚能 is concentrated energy, condensed energy,
聚能凝聚为组成我们宇宙的原子 energy that has condensed into the atoms that make up our universe.
爱因斯坦显示令原子相撞 Einstein showed that it's possible to release this energy
就有可能释放这股能量 by smashing atoms together.
它称为核聚变 It's called fusion,
也就是驱动恒星的力量 the same force that powers stars.
极细小亚原子粒子的物理特性 It's astonishing to realise that the physics of the very small subatomic particle physics
决定恒星的结构和性质 determines the structure and nature of stars.
从爱因斯坦的理论 From Einstein's theories,
我们学会怎样释放原子内的能量 we learned how to release the energy inside an atom.
科学界正设法模拟恒星的能量来源 Now science is trying to simulate a star's energy source
以便在实验室控制核聚变的强度 to control the power of fusion in a lab.
在英国, 牛津附近的这个实验室 Inside this laboratory near Oxford, England,
有一部8万磅重的机器 there's an 80,000-pound machine.
每天, 安迪寇克和组员 Every day, Andy Kirk and his team
都在地球上把它变成一颗恒星 transform it into a star, on Earth.
这部机器叫托卡马克装置 This machine is called a tokamak.
其实就是一个巨型磁瓶 It's effectively a large magnetic bottle,
一个盛载极热等离子体的笼 a cage to hold a very hot plasma.
我们能重塑恒星内的情况 We're able to recreate the conditions within a star.
在托卡马克装置内 Inside the tokamak,
氢原子很自然地互相排斥 hydrogen atoms naturally repel each other.
为令氢原子相撞 To smash hydrogen atoms together,
托卡马克装置把氢原子 the tokamak heats them
加热至逾3亿度 to more than 300 million degrees.
在极高温下 At these temperatures,
充满能量的氢原子以极速移动 the energised hydrogen atoms are moving so fast
无可避免地互相碰撞 they can't avoid smashing into each other.
加热原子, 热力就是动力 If you heat it up, heat is motion,
热粒子的动力足以压过排斥力 and the motion of hot particles will be enough to overcome the repulsive force.
所有人员请准备离开托卡马克装置 All personnel should prepare to leave the tokamak machine area.
当一切无误 When everything goes right,
就能得到宇宙间最棒的发电厂 the result is the single best power plant in the universe:
核聚变 nuclear fusion.
以每秒1000英里的高速移动 Travelling at a thousand miles a second,
氢原子互相碰撞并熔合 the hydrogen atoms smash into each other and fuse
形成一种新元素: 氦 creating a new element: helium,
和小量纯能量 and a small amount of pure energy.
氢较氦稍重 The hydrogen gas weighs slightly more than the helium.
燃烧过程导致失去质量 You lost mass in the process of burning.
失去的质量变成能量 That mass that you lost, the missing mass, turns into energy.
托卡马克装置只能维持核聚… The tokamak can only maintain fusion
极短时间 for a fraction of a second.
但真正恒星的核聚变持续几十亿年 But inside a real star, fusion continues for billions of years.
原因极简单: 大小 The reason is simple: size.
驱动恒星的引掣是重力 The engine which drives a star is gravity.
因此恒星很巨大, 是庞然巨物 That's why stars are big. Stars are huge.
需要极大重力才能压缩恒星 You need that amount of gravity in order to compress the star
以制造足以引发核聚变的热力 to create fantastic amounts of heat, sufficient to ignite nuclear fusion.
那就是恒星的秘密, 恒星发亮之因 That is the secret of the stars, that's why stars shine.
恒星核心的核聚变 Fusion at the core of a star
每秒产生10亿个核弹的爆炸力 generates the explosive force of a billion nuclear bombs every second.
恒星是巨型氢气弹 A star is a gigantic hydrogen bomb,
那为甚么它不会炸成碎片? so why doesn't it simply blow apart?
因为重力挤压着恒星的外层 It's because gravity is compressing the outer layers of the star.
重力和核聚变在这场激战中角力 Gravity and fusion lock horns in an epic battle.
这种紧绷状态持续 We have this constant tension between gravity,
重力想把恒星压碎成为碎片 which wants to crush a star to smithereens,
而核聚变释放的能量 and also the energy released by the fusion process,
却想炸散恒星 which wants to blow the star apart.
那股张力互相抗衡, 制造出恒星 And that tension, that balancing act, creates a star.
恒星一生都面对这种力量斗争 This power struggle plays out over the entire life of a star,
两股庞大的自然力量处于僵持局面 two awesome forces of nature in a dynamic stand'--off.
激战期间, 恒星爆发光和热 As that battle rages, the star blasts out light and heat,
但还有更具破坏力的东西 but also something far more destructive.
每束星光都踏上史诗式的旅程 Each beam of starlight makes an epic journey.
光以时速6亿7千万英里速度飞驰 Light travels at 670 million miles an hour.
光束能在1秒间环绕地球7次 A beam of light could travel around the Earth seven times in one second.
宇宙间没其它东西移动得更快 Nothing in the universe moves faster.
但大部分恒星都距离甚远 Yet most stars are so far away,
它们的光要几百、几千、几百万… their light takes hundreds, thousands, millions,
以至几十亿年才能到达地球 even billions of years to reach us.
因此当哈勃太空望远镜 So when the Hubble Space Telescope
望向宇宙偏远的角落时 looks into the far corners of our universe,
看到的是飞驰了几十亿年的光 it sees light that's been travelling for billions of years.
今天看到来自船底座伊塔星的光 The light we see today from Eta Carinae left that star
是远祖8000年前开始农耕时射来的 when our ancestors first farmed the land 8,000 years ago.
参宿四的光在500年前… Light from Betelgeuse has been travelling since Columbus discovered America,
哥伦布发现美洲时已发射出来 500 years ago.
太阳的光也需要8分钟才传到地球 Even light from our own sun takes eight minutes to reach us.
其实早在展开太空之旅前 But even before light starts its journey through space,
光已飞驰了几千年 it's already been travelling for thousands of years.
当太阳在核心把氢熔入氦之中 When the sir fuses hydrogen into helium in its core,
就创造出光子 it creates a photon of light,
光的粒子 a particle of light
新光线要走很远才到达恒星表面 That new ray of light has a long way to go just to reach the star's surface.
由于要穿越恒星 There's a whole star in its way,
所以, 光子诞生后, 走不了多远 and so when the photon is created, it doesn't get very far before,
就撞向其它原子、光子、中子等等 it immediately slams into another atom, another proton, another neutron, something.
被吸收, 再给射向另一个方向 It gets absorbed and then shot off in another direction.
因此光子很任意的在太阳内移动 And so it's sort of randomly moving around inside of the sun
很辛苦地逃出来 and it has to work its way out.
对光子来说 For the photons,
要撞上气体原子几十亿次 it's a wild ride smashing into atoms of gas billions of times
才能千辛万苦的逃离恒星内部 as they struggle to escape from inside the star.
整个过程有趣之处 What's funny about this whole process
是光子要花千千万万年 is that it takes the photon thousands and thousands of years
才能从太阳核心去到表面 to get from the core of the sin to the surface,
但一旦到达太阳表面 and yet once it hits the surface,
从那里到地球就只需要8分钟 it's only an eight-minute trip from there to here.
光子提供光和热 Photons are the source of light and heat,
但亦带来另一种更具破坏力的东西 but they also cause something far more destructive:
太阳风 the solar wind.
到达表面时, 光子会加热太阳外层 As they reach the surface, photons heat up the outer layers of the sun,
使之围绕恒星飞驰 sending it hurtling around the star,
形成强烈的湍流和强劲冲击波 creating extreme turbulence and intense shockwaves.
狂暴得我们也听得到 It's so violent, we can actually hear it.
由太阳和日球观测站人造卫星录得 Picked up by the orbiting SOHO satellite,
这是太阳的声音 this is the sound of the sun.
高速飞驰的气体亦产生强大磁场 The speeding gases also generate powerful magnetic fields.
恒星旋转时, 磁场相撞, 冲破表面 As the star rotates, the fields clash and burst through the surface.
巨大磁环迸发进入太空 Giant, magnetic loops erupt into space.
有些大得能让地球穿过去 Some are so large, the Earth could pass right through them,
周围还有几千英里空位 with thousands of miles to spare.
它们很壮观, 杀伤力极大 They are spectacular and they are deadly,
把大量电粒子射到太空深处 blasting a stream of electrical particles deep into space.
这就是太阳风 This is the solar wind.
它能破坏宇宙飞船和人造卫星 It can damage spaceships and satellites,
甚至危害航天员的生命 even put astronauts' Iives in jeopardy.
为了了解磁环怎样触发太阳风 To discover how the magnetic loops trigger the solar wind,
加州理工学院一组科学家 a team of scientists at Caltech
在地球重塑恒星表面 recreate the surface of a star, right here on Earth.
实在令人很兴奋 It's very exciting to be able...
在实验室里 to create in a laboratory
制造跟太阳表面相同的物理现象 the same sort of physics that are on the solar surface.
我们无法前去, 无法派探测器去 We can't go there, we can't even send probes there,
但我们能试着研究那里的情况 but we can try to study what's happening there.
无空气舱模拟太空的真空状态 An airless chamber simulates the vacuum of space.
庞大的电流 An enormous electric current
制造出一对人造磁环 produces a pair of man-made magnetic loops.
我们在实验室制造的等离子环 The main difference between the plasma loops we make in the lab
跟太阳表面那些的主要分别是大小 and the ones on the surface of the sun is just their size.
我们在实验室制造的, 约这么大 The ones we make in lab are, you know, about this big,
太阳表面的, 是地球大小的许多倍 and the ones on the surface of the sun can be many times the size of the Earth.
实验显示当磁环在实验室内相撞 Their experiment reveals that when magnetic loops clash in the lab,
就触发大量能量迸发 they trigger a massive burst of energy.
当巨型磁环在恒星表面相撞 When giant loops collide on the surface of a star.
释放的能量令温度飙升 the energy released sends temperatures soaring,
从1万度急升至1000万度 from 10,000 to 10 million degrees.
那股极大热力触发太阳风 That extreme heat triggers the solar wind,
令数百万吨计的粒子涌进太空 sending millions of tonnes of particles streaming out into space.
恒星越大, 太阳风的杀伤力就越大 The bigger the star, the more deadly the wind.
若地球以相同距离 If we were orbiting a star like Eta Carinae
围绕船底座伊塔星之类的恒星运转 at the same distance,
地球准会变成炼狱 it would be hell on Earth, quite literally.
射向地球的能量 The amount of energy blasting down on the Earth
能剥去大气层, 烧沸海洋, 熔掉表面 would strip away our atmosphere, boil our oceans, melt the surface.
了解恒星的运作或能助我们自保 Understanding how stars work could help us protect ourselves
方法是预测它们最大的破坏力 by predicting their most destructive forces.
但当恒星消亡, 我们就无法自保 But there's nothing we can do to protect ourselves when a star dies.
进入最后阶段, 恒星消灭周遭一切 In its final moments, it annihilates everything around it
从诞生伊始 From the moment of its birth
每颗星星 every star
注定就会消亡 destined to die.
燃料会耗尽 Its fuel will run out
然后, 重力将战胜核聚变 Then, gravity will win the battle with fusion,
触发连串摧毁恒星的事件 triggering a chain of events that will destroy the star.
我们的太阳亦不例外 Our sir is no exception.
每一秒 Every second,
其核心燃烧6亿吨氢燃料 it burns through 600 million tonnes of the hydrogen fuel in its core.
以这速度计算, 氢约70亿年就耗尽 At that rate, the hydrogen will run out in about seven billion years.
随着氢渐少, 核聚变的速度亦减慢 As the hydrogen gets used up, it slows down the fusion at the star's core.
这就让重力占上风 This gives gravity the edge.
随着核聚变往外推的力度减轻 With less fusion pushing outward,
重力挤压恒星向内压缩 gravity crushes the star in on itself.
但核聚变反击, 加热恒星外层 But fusion fights back heating the star's outer layers.
给气体加热, 气体就会膨胀 When you heat up a gas, it expands,
因此太阳将会变大 and so the sin will actually expand up.
太阳直径不再是现在的100万英里 Instead of being a million miles across like it is now,
它不断膨胀, 至直径约达1亿英里 it will swell up until it's about a hundred million miles across.
我们的太阳将变成红巨星 Our sun will become a red giant.
试想像公元70亿年时的日出 Imagine a sunrise 7 billion A.D.
升起的, 不再是迷人的小巧黄圆盘 It's not just a little yellow disc coming up all cheerful and nice.
看到的, 或是一个发胀的火红圆盘 What you would see is a huge, swollen, bloated, red disc
慢慢从地平线爬上来 slowly reaching up over the horizon
太阳完全升起时 and when the sun is fully up in the sky,
向地球射出高温热力 it's blasting down heat on the Earth.
那就像把头伸进高温烛炉里 It would be like sticking your head in an oven set to broil.
地球气温将高达几千度 Temperatures here on the Earth will reach thousands of degrees.
海水将会沸腾, 群山将会熔掉 The oceans will boil, the mountains will melt,
我们将面临世界末日 and we'll have the last nice day on the planet Earth.
然后, 发胀的恒星将吞没地球 Then, the bloated star will engulf the Earth.
但这个红巨星正步向自毁 But the giant red star is self-destructing.
其核心越来越不稳定, 很危险 Its core becomes dangerously unstable.
当再没有氢气可作燃料 With no hydrogen left to fuel it,
恒星开始燃烧氦, 并使之聚合成碳 the star begins burning helium and fusing it into carbon.
这时, 恒星从内到外地逐步自毁 The star is now destroying itself from the inside out.
从核心迸发狂暴的能量到表面 blasting violent surges of energy from its core to its surface.
这些能量波炸去恒星的外层 These energy waves blow away the star's outer layers.
慢慢地 Slowly
崩溃 it disintegrates.
恒星 The star
消亡 is dead.
只剩下一个极热的稠密核心 All that remains is an intensely hot, dense core.
红巨星已变成白矮星 The red giant has become a white dwarf.
当恒星到达白矮星阶段 By the time a star reaches the white dwarf stage,
核聚变过程已停顿 the fusion process has stopped.
引掣终于停下来 The engine has finally come to rest
太阳灭亡时 Our sun will end its life as a white dwarf
将变成不比地球大的白矮星 no larger than the Earth,
但密度就较地球高100万倍 but a million times denser.
白矮星是奇妙物体, 密度极高 A white dwarf is a pretty amazing object; it's incredibly dense.
若能把方糖般大的白矮星 if you could take a sugar cit>e sized chunk of white dwarf
放在地球表面 and put it on the surface of the Earth,
它因密度极高, 会直接掉到地底 it would be so dense it would fall right through the ground
在白矮星的核心 At the heart of a white dwarf,
天文学家认为藏有巨大的纯碳晶体 astronomers believe there's a giant crystal of pure carbon,
一颗直径达几千英里的宇宙大钻石 a cosmic diamond thousands of miles across.
想到太阳将沦为一团又黑又冷的煤渣就有点悲伤 The idea that the sun will become this sort of cool dark lump of cinder material is kind of sad.
但那将是… But that really will be...
无数万亿克拉的钻石 sort of a trillion, trillion, trillion-carat diamond.
想一想, 天上的钻石! Think of that, a diamond in the sky.
但恒星能创造出较巨钻更珍贵之物 But stars can create something much more precious than a massive diamond.
当比我们太阳大的恒星灭亡时 When stars much bigger than our sun die,
过程就更狂暴 their death is much more violent.
但垂死时, 它们创造出生命所需的东西 But in dying, they create the building blocks of life.
巨大的恒星高速旋转, 明亮地燃烧 Giant stars live fast, burn bright,
剧烈的结束 and die hard.
但它们的消亡带来生机 But from their destruction comes life.
巨型恒星的消亡创造出宇宙的要素 The death of massive stars creates the building blocks of the universe,
生命的种子 the seeds of life itself.
距离地球不足600光年之处 Less than 600 light-years from Earth,
巨型的恒星参宿四接近死亡 the monster star, Betelgeuse, is near death.
以太空年计算 Well, in space years.
它较我们太阳年轻 It's younger than our sun, millions,
只有几百万岁, 不是几十亿岁 not billions, of years old.
但其核心的核聚变就剧烈得多 But the fusion at its core is far more intense.
参宿四跟太阳截然不同 Betelgeuse is a different beast from the sun entirely.
它是个火红超巨星 It's a red super-giant.
原因是… And the reason is because...
参宿四巨大得多 Betelgeuse is more massive.
它的质量是太阳的20倍 It has 20 times the mass of the sun,
意味其核心的活动 and that means what's going on in its core
跟太阳的很不同 is very different than what's going on in the sun's.
巨型恒星产生的压力和温度 Massive stars generate pressures and temperatures
是宇宙里最厉害的 greater than anywhere else in the universe.
参宿四的重力极大 The gravity of Betelgeuse is so powerful
能令愈来愈大的原子相撞 it can smash together bigger and bigger atoms.
巨型恒星的核心就像一间工厂 The core of a massive star is a kind of factory,
制造愈来愈重的元素 manufacturing heavier and heavier elements,
亦因而导致恒星灭亡 which is what also leads to the star's destruction.
一旦产生铁元素, 恒星就会完蛋 Once it makes the element iron, the star is doomed.
在科幻小说的世界 In the world of science fiction,
有许多消灭恒星的机器的想法可能是这样 there are many ideas about what a star-killer machine might be like.
想不到的是, 元凶是平平无奇的铁 Strangely enough, it's as run-of-the-mill as something as iron.
对于恒星, 铁是宇宙间最危险元素 简直就是毒药 To a star, iron is the most dangerous element in the universe.It's poison.
铁吸收能量 Iron absorbs energy.
巨型恒星一旦创造铁 From the moment a massive star creates iron,
就注定命不久矣 it has only seconds to live.
恒星设法把能量注入铁球 The star is trying to dump energy into that iron ball
尝试使之熔合, 但不果 and trying to make it fuse, but it can't.
铁球抢去恒星的能量 And so that ball is robbing the star of energy,
而那些正是维持恒星生命的能量 and it's that energy that is supporting the star itself.
因此, 核心一旦开始制造铁 So as soon as that iron starts to be created in the core,
恒星就是判了自己死刑 the star has written its own death sentence.
设法压破恒星的重力 The battle between gravity, trying to crush the star,
和设法炸散恒星的核聚变之战争 and fusion, trying to blow it apart,
终于结束 is over.
有了铁, 核聚变就到了死胡同 With iron, fusion hits a dead end.
重力总能获胜 Gravity always wins.
铁核心崩塌 The iron core collapses.
恒星外层向核心猛烈撞击 The outer layers of the star slam down into it
产生大规模爆炸 and a huge explosion is generated.
这是宇宙间最狂暴的事件, 超新星 its the single most violent event in the universe, a supernova.
短短几秒间 In just a few seconds,
超新星产生的能量远较我们太阳多 supernovas create more energy than our sun ever will.
开始制造铁之后的几秒内 Within a couple of seconds after beginning to make iron,
恒星爆炸, 成为超新星 star explodes in a supernova.
下次拿着铁煎锅时要好好想一下了 So think about that when you're holding one of your iron frying pans.
铁能在几秒间消灭一颗恒星 The iron killed a star in just a few seconds.
是非常危险的东西 Dangerous stuff.
各地的望远镜在天际搜索超新星 Telescopes around the world scan the skies for supernovas.
1987年, 附近银河系出现一道强光 In 1987, a brilliant light appeared in a nearby galaxy,
在17万光年之外 170,000 light years away.
这些照片纪录一颗巨型恒星消亡后 These pictures record the events following the death of a massive star,
直径几万亿英里的火球飞向太空 as a fireball trillions of miles wide hurtles out into space.
但没有恒星开始裂开 But there's no record of the actual moment of death,
确实消亡时刻的纪录 when the star first ripped itself apart.
要了解巨型恒星爆炸时的内部情况 The only way to know what happens inside a massive star when it explodes
唯一方法就是自制超新星 is to make our own supernova.
这些恒星爆炸时的奇妙之处 What's amazing when these stars explode
就是它们几乎内外翻转 is that they almost turn inside out.
在纽约, 罗彻斯特这间实验室里 Here in this lab in Rochester, New York,
科学家正用巨型激光制造超新星 scientists are making a supernova with a giant laser.
望远镜看不到垂死恒星的内部 Telescopes can't see inside the dying star.
有了这部激光仪器 With this laser,
就能侦测到恒星爆炸时的过程 we can detect the processes that occur as the star explodes.
使用这些工具是极刺激的事 Working with these tools is the most exciting thing I can imagine doing.
这巨型机器扩大一道激光束的力量 This massive machine amplifies the power of a single laser beam,
扩大许多许多倍 a thousand million million times.
能量足以供给30个… That's enough power to supply 30 cities
像底特律般大的城市使用 the size of Detroit.
所有能量给导往一个针头般大范围 And all that energy will be directed toward an area the size of a pinhead
看看这个充当恒星核心的细小目标 Look at this tiny target as a star's core.
激光模拟宇宙间最猛烈的爆炸 The laser simulates the most violent explosion in the universe.
发射激光时, 这里绝对不安全 This would not be a safe place to be when the laser was fired.
若人体给全部这些激光束击中 If a human were struck by all these laser beams,
能在他们身上钻穿一个洞 it would drill a hole right through them.
离开受影响的范围 Now going to closed access in the laser bay.
锁门 Bay doors locked.
完成最后准备 Final preparations are complete.
5, 4, 3, 2, 1 Five, four, three, two, one.
目标遭激光汽化 The target is vaporised by the laser.
爆炸只维持了0.00001秒 The explosion lasts just a hundred thousandth of a second,
但高速摄影机拍到冲击波向外扩散 but a high-speed camera captures the Shockwave expanding outwards.
部分内部物质射出来 Some of the inner material comes out
跟外部物质对调位置 and trades places with the outer material,
内外翻转就是恒星爆炸时的现象 and that turning inside out is just what happens in a stellar explosion.
恒星核心深处的物质 Material from deep inside a star's core
随着冲击波射进太空 surfs the Shockwave out into space.
在爆炸极热且混乱的情况中 In the extreme heat and turmoil of the explosion.
打造出较重的元素 heavier elements are forged.
包括金、银和铂 Among them, gold, silver and platinum,
因为没多少时间让元素形成 and because there's so little time for the elements to form,
所以它们是宇宙间最罕见珍贵的 they're the rarest and most valuable in the universe.
银、金等元素在恒星爆炸期间… Silver, gold, everything else, are created by the explosion of the star,
由释放的庞大能量制造而成 by the immense energy released,
它们就是这样形成的 and that's how they come to us.
但即使在宇宙间最猛烈的爆炸后 But even after the universe's most violent explosion,
仍会留下一些东西 there's something left behind.
科学家以前认为在超新星爆炸后 We scientists used to believe that after a supernova explosion,
恒星会炸成碎片, 甚么也没留下 a star would literally blow itself to bits and there would be nothing left
这想法是错的 Well, we were wrong.
有一具残骸 There's a corpse,
超新星爆炸的残骸 a corpse of a supernova explosion,
科学界所知极奇异的物质: 中子星 some of the most exotic matter known to science, called a neutron star:
实心的核子物质 solid nucleonic matter,
宇宙间物质的最奇妙状态 the most fantastic state of matter in the universe.
超稠密的核心变成中子星 The super-dense core is now a neutron star.
直径约20英里, 难以置信的重 It's around 20 miles across and unbelievably heavy.
密度极高 It's incredibly dense.
1立方厘米 Just a cubic centimetre,
方糖般大的中子星物质 just a size of a sugar cube of neutron star material
等于美国所有汽车结合起来那么重 would weigh as much as all the cars in the United States of America combined
垂死的恒星不仅留下中子星残骸 The dying star doesn't just leave the corpse of a neutron star,
还把新元素射到太空 it blasts the new elements far out into space.
这些云含有宇宙的构块 These clouds contain the building blocks of the universe.
我们所知和热爱的, 都由星尘建造 Everything we know and love is built from this stardust
只有超新星有足够能量… Only a supernova has enough energy to fuse these elements
熔合这些对生命如此重要的元素 which are so essential for life.
没有超新星, 就没有生命 Without supernovae, there's no life,
没有你, 没有我 there's no you and there's no me.
巨型恒星消亡时 When massive stars die,
把星尘散布于宇宙 they seed the universe with stardust.
充满各种元素 例如氢 Full of elements like hydrogen
碳 carbon
氧 oxygen
硅 silicon
铁 iron.
这些原料可以制造新恒星 The raw materials to build new stars,
太阳系、行星, 当然还有我们 solar systems, planets and, of course, us.
我们身边的一切都源自恒星的核心 Everything we see around us once blasted out from the core of a star.
你或疑惑甚么是星尘 You may wonder what stardust is.
其实, 你也是星尘 Well, you're stardust,
因为你体内每个原子 because every atom in your body
都是在恒星狂暴核心内制造的 was produced inside the fiery core of a star
你左手的原子 The atoms in your left hand
跟你右手的原子或来自不同恒星 may come from a different star from the atoms in your right hand,
但你名副其实是「恒星的孩子」 but you are literally a star child.
消亡已久的恒星 Long-dead stars
提供的星尘创造了我们的太阳系… provided the stardust to create our solar system,
行星及星体上的一切 the planets and everything on them.
所以, 其实你由碳组成, 由氧组成 So you're made of carbon, you're made of oxygen,
血液里还有铁 there's iron in your blood.
全部都是在恒星核心内制造的 All of those things had to be generated inside the core of a star.
没有其它方法能得到 There's no other way to get them.
思考恒星时, 不妨环顾四周 So when you think about star stuff, look around you.
组成你的一切元素 Everything that you're made of,
组成你身边万物的一切元素 everything the world around you is made of,
都来自许久前爆炸的恒星的核心 had to come from the belly of a star that blew up a long time ago.
就连我们太阳的原子亦循环再用 Even the atoms in our own sun are recycled.
它们已是第三或第四代 They're third or fourth generation,
是许久前垂死恒星射进太空的碎片 leftover debris shot into space by dying stars a long time ago.
我们的太阳就像我们的继母 Our sun is our stepmother.
我们的生母死于超新星爆炸 Our true mother died in a supernova explosion
产生组成我们身体的各种元素 to give birth to the elements which made up our body.
但为何一众诗人、作曲家 But how come the poets and the songwriters,
不写诗篇歌颂我们的生母? how come they don't write poems to our true mother?
可能是因为他们不理解物理 It's perhaps they don't understand physics
不了解恒星演化的定律 and the laws of stellar evolution.
我们活在恒星时代 We live in an age of stars,
但这时代将会终结 but it will come to an end.
宇宙间的氢有限 There's only so much hydrogen in the universe.
几万亿年后就会耗尽 Trillions of years from now, it will all be used up.
当氢耗尽, 就不会再有新恒星 And when there's no hydrogen left, there will be no new stars.
我们活在宇宙历史上一个很短时期 We live in a very brief period in the history of the universe,
一个仍有恒星照耀天际的时期 when we still have stars illuminating the sky,
恒星创造生命, 但它并不恒久 stars creating life as we know it, but it's not gonna last forever.
恒星早晚都会开始逐渐消逝 Sooner or later, the stars will begin to blink out
首先, 巨型恒星将会烧尽 First, the massive stars will burn out.
然后是中等恒星, 例如我们的太阳 Then, mid-sized stars like our sun,
只留下最小的 leaving only the smallest
几万亿年后, 它们亦将消逝 Trillions of years later, they too, will fade away.
慢慢地, 无可阻挡地 Slowly, inexorably,
宇宙将变得较寒冷黑暗 the universe will get colder and darker
直到最后一颗恒星烧尽 until the last star burns out
到时宇宙便再次变得黑漆漆 and the universe becomes dark once again.
届时, 恒星时代将会结束 The age of stars will be over.
老实说, 宇宙的未来看似黯淡 Honestly, the future of the universe looks kind of grim,
但你能往好的方面去想 but you can take something positive out of that
这是活着的最佳时刻 This is the best time to be alive.
这是生命能繁衍, 恒星能形成之时 This is the time where life can flourish, stars can form.
我们正处于宇宙的黄金时代 We are in the golden age of the universe right now.
可以说, 这是宇宙的生命勃发季节 We live in a season for life in the universe, if you will,
能维持几十亿年 that lasts for a few billion years.
因此, 我很珍惜欣赏万物的现况 And that makes me, at least, appreciate the way things are right now,
因为以前不是这样的 because they weren't always that way
亦不会永远是这样的 and they won't always be.
我们活在恒星发亮照耀夜空的时期 We live in the stage where stars glow and illuminate the night sky,
恒星创造生命的时期 when stars create life as we know it
我们活在宇宙最棒的阶段 We live in the best of all stages of the universe.
暂时而言, 恒星将继续塑造宇宙 For now, stars will continue to shape our universe.
带来建立新世界的构块 Generating the building blocks of new worlds,
创造新恒星, 并以光明填满黑暗 creating new stars, and filling the darkness with light.
翻译/摘订时间轴/校对：啥时候摇中