星际里的世界千奇百怪… Across the galaxy lie exotic worlds...
有些全都是水 some made entirely of water,
还有喷涌着毒气的 others stewing with poisonous gas.
何种生物能茁壮成长于斯地呢？ What kinds of creatures thrive in these places?
他们会类似于地球上的生命么… Would they resemble beings on Earth...
…抑或生命会呈现新的意想不到的形式么？ ...or could life take on new and unexpected forms?
外星人是何模样呢？ What do aliens look like?
科学频道 - 穿越虫洞 2x10 Science.Channel - Through the Wormhole 2x10
空间 时间 生命本身 Space,time,life itself.
宇宙的秘密，尽在穿越虫洞 The secrets of the cosmos lie Through the Wormhole.
外星人是何模样呢？ What Do Aliens Look Like?
它们就在那里 They're out there.
我们能够看到它们 We can see them.
人类史上首次 For the first time in human history,
我们知道了宇宙遍布行星 we know the Universe is filled with planets
其怪异超过了我们的想象 - stranger than we could ever have imagined --
行星有可能定居有外星生命 planets that might be home to extraterrestrial life.
但是这些生物会是何种模样呢？ But what will these creatures look like?
我们都是我们环境的产物 We're all products of our environment.
如果生我养我的星球 充满二氧化碳气体 lf l was born on a planet with carbon dio xide air
重力比我们地球弱三倍 and gravity three times weaker than the Earth's,
我的模样有可能是…这样 l might look like...this.
在一颗行星 重力是地球的五倍 On a planet with five times more gravity than Earth,
恒星持续不断以太阳风轰击它 and a star that constantly blasted it with solar storms,
我可能看上去是这样 l might look like this.
我们无法知道外星人的真面目 We can't know the face of an alien
除非我们亲眼所见 until we're staring at it.
不过如搜寻嫌疑犯的侦探一样 But like detectives on the hunt for an unknown suspect,
生物学家和行星科学家 biologists and planetary scientists
正着手拼凑谜团 are beginning to piece the puzzle together.
有些线索在外头 Some of the clues are out there,
但其中很多就在这里 but a lot of them are right here.
每天放学回家 To get home from school every day,
我都得穿过一座阴森老宅 l had to cut through the yard of a scary,old house.
我从未见到有人进出过 l never saw anyone come in or out of it,
但有人或什么住在里头 but someone or something lived there.
我只能想象谁或者什么有可能在那里 l could only imagine who or what it might be.
哈佛大学古生物学家安德鲁.诺尔 Harvard paleontologist Andrew Knoll
毕生都在研究 has spent his life
超乎我们想象的生物 studying creatures beyond our wildest imaginations.
你步入这样的博物馆 One of the things you learn when you go
所获悉的一件事情 through a museum like this is
那就是 很难想象 He is that not only is it hard to imagine
生命有可能存在于另一个星球 what life might be on another planet,
然而，更难想象的是 其中有些生命 but it's hard to imagine some of the life
已经存在于这个星球上了 that has existed on this planet.
有谁想得到有过恐龙这样的东西 Who would guess that there were things like dinosaurs
居然没有骨骼？ in the absence of their bones?
在过去8年里 For the past eight years,
安德鲁担当了航天局的火星漫游者任务的 Andrew has served as mission biologist
生物学家 on NASA's Mars Rovers.
此角色唯有他能胜任 lt's a role he's uniquely suited for
因为他具有广泛的地球生命的专业知识 because of his expertise in the vast array of life on Earth,
他能够从其岩石中 and his ability to read the history of a planet
读出行星的历史 from its rocks.
我们往往认为地球 There's a tendency for us to think about the Earth
就是我们今天看到的周围的这些东西 in terms of the things we see around us today.
但是地质记录所告诉我们的一件事 But the one thing that the geologic record tells us
是一直存在着一系列的地球 is that there have been a series of earths,
我们所看到的身边的地球 - and that the Earth that we see around us --
所有的植物 动物 all the plants and the animals
大气层的成分 - and the composition of the atmosphere --
都已经是最终成员了 are really an end-member,
这个最终状态经过了漫长地变迁 the end state of a long series of transitions
历经了40多亿年 that have happened over 4 billion years.
比如 这块石头 For example,this rock,
它形成于35亿年前 which formed about 3.5 billion years ago,
全是铁矿物 is full of iron minerals,
这表示铁必须得通过海水来运送 which means that iron had to be able to be transported
它唯有在缺氧的海水里 through seawater,and it can only do that
才能做到这一点 in seawater that contains no o xygen.
发现此类石头遍布全球 The discovery of rocks like this all over Earth
表明它存在的 shows that for nearly the first 4 billion years
近40亿年里 of its existence,
我们的大气层几乎没有氧气 our atmosphere had almost no o xygen.
就是说地球对我们一直是有毒的 That Earth would have been to xic to us.
现在 还有些事情有点出乎意料 Now,there are other things that are sort of unexpected
就在我们往深里看地球的历史时 when we actually look at deep-earth history.
这块石头实际上是冰川沉积物 This rock was actually deposited by glacial ice
已经超过6.35亿年了 about 635 million years ago.
此类石头确实形成在 There are rocks like this
此时的整个地球上 that formed literally all over the world at this time,
它向我们表明冰川曾到达了 and it shows us that there was glacial ice
赤道的海平面 at sea level at the equator.
事实上 大部分地球 - ln fact,much of the Earth --
没准是整个地球 - 都覆盖着冰 perhaps most of the Earth -- was covered with ice,
有时也称为雪球地球 sometimes called a snowball Earth.
这各种地球 - These various earths --
炎热的 寒冷的 或多或少的氧气 - hotter,colder,with more or less o xygen --
基本上就是异域世界 were essentially alien worlds.
因此 对于安德鲁来说 探索外星人 So,for Andrew,the best place to discover
会是何种模样的最佳点就在我们自己的化石记录中 what aliens might look like is in our own fossil records.
这些是三叶虫 These are trilobites.
现在 你看这个 Now,when you look at this,
你会看到很熟悉的东西 you'll see things that are familiar.
有接缝的分段身子 There is a jointed,segmented body.
有接缝的分段肢体 There are jointed,segmented legs.
你可能会说 And you might say,
“啊 看上去像是虾或是昆虫” 一点没错 "Well,that looks like a shrimp or an insect," and that's right.
生物学家 Biologists
称这些地球史上的生命形式的重复性为 call these repeated similarities of life-forms
“会聚” over Earth's history "convergence."
一个行之有效的形状 One shape that works well
会一而再 再而三地重复 gets repeated over and over again.
这种巨大的海洋生物看上去像是鲸鱼 This giant sea creature looks like a whale,
但它实际上是已经绝种的蜥蜴 but it is actually an extinct lizard.
在过去2.5亿年间一再重复 Repeatedly over the last 250 million years,
陆地上的脊椎动物再次侵入海洋 vertebrate animals on land have re-invaded the oceans.
每次它们如此做时 And every time they've done so,
都会产生出这样巨大的海洋怪物 they've given rise to these giant sea monsters.
长头龙 Kronosaurus.
7000万年前 海洋里有过蜥蜴 70 million years ago,there were lizards in the sea.
它们同样是大型的 They were equally large.
在我们有生之年里 存在有鲸鱼 ln our own lifetimes,there's whales.
如果过去的地球 lf Earth in the past
一直就如围绕其它恒星的行星那么异样 has been as alien as planets orbiting other stars,
那么外星人就是你在电影里所见到的 - then aliens you've seen in movies --
蜥蜴有两只眼睛 两条胳膊 两条腿 - lizards with two eyes,two arms,and two legs --
大差不离 might be pretty close to the mark.
我必须承认 l must admit,
我看过大量的50年代以来的老的怪物电影 l watch a lot of old monster movies from the 1950s
专门从物理学角度去看 specifically looking at the physics
说道 不不不 不是那回事 and saying,"No,no,no. That's not gonna work,"
或者说 噢 那很出色 or "Ooh,that's really good."
芝加哥大学的教授迈克尔.拉巴贝拉 University of Chicago Professor Michael Labarbera
是一位生物力学专家 is an expert in biomechanics.
他试图预测 He's trying to predict
外星人是如何行走 飞翔和游水的 how aliens will walk,fly,and swim
通过搜寻动物运动的基本规律 by searching for the basic rule of how animals move.
你可以称其为 You could call it
运动的最小公分母 the lowest common denominator of locomotion.
鲎这样的东西 Things like horseshoe crabs
爬上海滩产卵 were crawling out on the beach and laying their eggs
此时翼龙则在天上飞翔 when pterodactyls were flying in the sky.
我们与这些动物所分享的特征之一 One of the features that we share with these animals
就是杠杆式的骨架 is a lever-type skeleton.
我手上有杠杆 l have levers in my hands.
就是它让我做如此动作 That's what allows me to do that.
我有杠杆在我的肘部 肩部 l have levers in my elbows,in my shoulders.
基本想法是 The basic idea is
利用具有较高机械优势的杠杆 to use a lever that has a high mechanical advantage,
把大量肌肉力量提供给 that delivers a lot of the muscle force
杠杆的外端 to the output side of the lever.
成功的布局 Successful designs
如将四肢与坚硬骨骼连接起来 like jointed limbs and hard skeletons
一次又一次表现在化石记录中 show up again and again in the fossil record.
我们今天看到它们就在我们身边 We see them all around us today,
迈克尔期盼在别的世界里也能看到它们 and Michael expects to see them on other worlds,too.
并不在乎骨骼是不是 And it doesn't matter whether the skeleton
我们骨骼那样的羟磷灰石所构成 is made out of hydro xyapatite like our bones,
还是这种动物的甲壳素所构成 made out of chitin like this animal,
或者是碳纳米管构成 or carbon nanotubes.
一旦规则容易到了足以让 When a principle is easy enough
自然选择成为了偶尔发现 for natural selection to stumble across,
那么就会一而再 再而三地演化 then it will evolve over and over again.
在这个星球上 独立演化 On this planet,it has evolved independently
在不同时期至少有了六次 at least half a dozen different times.
有充分理由相信 And there's every reason to believe
它们普遍适用于 they will be just as common
任何星球的任何生态系统 in any other ecosystem on any other planet.
连接肢体的躯干动作如杠杆 A torso with jointed limbs acting as levers.
这是对外星人的很恰当的基本解剖 lt's a good basic anatomy of an alien,
但我们能否更进一步想象它们真实的形态呢？ but can we get closer to imagining their true form?
在19世纪 ln the 19th century,
查尔斯.达尔文保留了一系列的笔记 Charles Darwin kept a series of notebooks
记载了动物的形状是如何进化成 chronicling how the shapes of animals had evolved
去适应它们所处的环境 to adapt to the environments they lived in.
其它星球上的生命之书会是啥样子的呢？ What would a book of life on other planets look like?
解剖适应可能在异域环境中的发展 What mind-bending,anatomical adaptations
究竟有何匪夷所思之处呢？ might develop in alien surroundings?
环境塑造生物依赖它们的生态 The environment shapes creatures depending on their ecology.
大气的密度 Density of the atmosphere,
不管你是否有覆盖全球的海洋 whether or not you have a world-covering ocean,
都将在历史上形成巨大的差异 is gonna make a big difference in the history
从而 构成了生物体的形状 and,thus,in the shape of the organisms.
这就是为什么 Which is why
要了解外星人的模样 to know what aliens look like,
我们就必须更多地了解它们生存的星球 we must learn more about the planets they live on.
一直到最近 Until very recently,
我们都没有其它行星存在的证据 we had no proof other planets existed,
更别说它们的地貌及大气层 let alone any idea what their landscapes or atmospheres
会是何种模样 might be like.
然而现在 作为人类史上首次 But now,for the first time in human history,
我们能够看到远在我们太阳系以外的世界了 we can see worlds far outside our solar system.
现在我们知道了E.T.（外星人）可能居住的地方 And now that we know where E.T.s could live,
我们越发接近揭露它们隐匿的面孔了 we're getting closer to revealing their hidden faces.
我们若想知道外星人的模样 lf we want to know what aliens look like,
我们首先得知道它们居住之地的一些情况 we first have to know something about the places they live.
直到最近 这是不可能的 Until recently,this was impossible.
我们的望远镜只能观看恒星 Our telescopes could only see stars,
看不到其周围的行星 not the planets that orbit them.
如今 外星人猎手已有了专门的研究飞船 Today,alien hunters have a dedicated research ship
漂浮在距离地球2000万英里的地方 floating 20 million miles from Earth,
它发现的新世界数以千计 and it's discovering new worlds by the thousand.
3…2… 3...2...
点火 Engines start.
起飞 Zero.
德尔塔Ⅱ载着开普勒升空了 And liftoff of the Delta ll rocket with Kepler.
2009年 ln 2009,
航天局发射了其最新型太空望远镜 - NASA launched its latest space telescope --
开普勒 Kepler.
其目的不是为了拍照 lt's designed not to take pictures,
而是侦测遥远恒星亮度上 but to detect the tiniest changes
细微的变化 in the brightness of distant stars.
其目标是银河系我们所在的旋臂上的一片区域 lts target area is a patch of our arm of the Milky Way
从我们这里一直延伸出去有3000光年远 stretching out 3,000 light-years away from us.
哈佛大学教授迪米塔.萨瑟罗夫 Harvard professor Dimitar Sasselov
是开普勒首席科学家之一 is one of Kepler's lead scientists.
用开普勒望远镜 The beauty of how the Kepler telescope
探索小如地球的行星的方法 discovers planets as small as the earth is the method,
我们称其为凌日法 which we call the transit method.
这很容易理解 lt's very easy to understand.
就是 行星在其轨道上 So,the planet is passing on its orbit
在恒星的面前经过 in front of the star.
它的阴影造成星光有一点点昏暗 lts shadow causes that light to dip just a little bit,
这样一来我们就知道有行星的存在了 and that's how we know there is a planet there.
到开普勒完成其使命时 By the time Kepler is done with its mission,
迪米塔预计它将会发现 Dimitar expects it will have found
约100颗地球大小的行星 around 100 planets the size of Earth.
然而它所寻找的大量的行星 But the vast majority of the planets it is finding
几乎与我们的世界毫无共同之处 have almost nothing in common with our world.
开普勒已经有了一八宝箱的怪异行星 Kepler already has a treasure chest
如果你愿意的话 - of weird planets,if you will --
非常有趣的 各种各样的行星 very interesting,diverse planets.
我们有开普勒 - 10号星 它坚如钢铁 So,we have Kepler-10,which is as hard as iron.
接着我们有两三颗行星 Then we have two or three planets
在六颗行星组成的开普勒 - 11星系里 in the Kepler-11 system of six.
其中的一两颗是水行星 One or two of them are water planets --
一片汪洋 endless ocean.
接下来我们的行星 Then we have planets
几乎是浓密的大充气球或发泡塑料 almost the density of a beach ball or styrofoam.
或许最有趣的开普勒发现 Perhaps the most intriguing of Kepler's discoveries
是约300倍的超大尺寸版本的地球 - are around 300 super-sized versions of Earth --
岩石构成的行星 但要重上5倍 planets made of rock,but up to five times as heavy.
要说有人能想象其景色 lf anyone can imagine the landscapes
外星人会在那里慢跑 游泳 骑行 where aliens might jog,swim,or glide,
那就是戴安娜.瓦伦西亚 it's Diana Valencia.
业余三项全能运动员 Part-time triathlete,
她是首批剖析这些超级地球的 she's one of the first geologists
地质学家之一 to break ground on these super earths.
我没有锤子 l do not have a hammer.
我不破碎石头 l do not break up rocks.
我所做的是建立数学模型 What l do is l do numerical models
来了解地球的运作 to understand how the Earth works
并用它来了解 and use that to understand
更大或更小的行星是如何运作的 how bigger earths and similar planets work,as well.
为了了解 To understand
超级地球是否能够存在生命 whether the super earths could harbor life,
戴安娜瞄准推动岩石行星的 Diana is zeroing in on the basic geological engine
基本地质引擎 - that powers rocky planets --
板块构造 plate tectonics.
行星坚硬外壳运动的 The movement of a planet's hard outer crust
推手是其底下 is driven by a hot and viscous layer
高温粘稠的半融化岩石 of semi-molten rock below it
其活动宛如一罐冒泡的蜂蜜 moving much like a jar of bubbling honey.
这个实验向我们表现了大致的情况 This experiment here shows us in broad lines what happens.
地幔是一种非常粘稠的液体 The mantle is a very viscous fluid,
两种液体对温度都很敏感 and both fluids are very sensitive to temperature.
我们打开这个来加热模拟地球的引擎 So,as we turn this heat up to simulate Earth's engine,
你就会看到在其表面以下的活动 you will start seeing motion underneath the surface.
现在你看到了翻滚 Now you see the overturn.
现在你看到物体 Now you start seeing things
往各个方向活动 that are moving all sorts of directions.
不只是向上运动 lt's not just moving up.
随着温度的提升 As heat rises,
它在地幔中形成了对流体 it forms convective cells in the mantle,
这引发了表面板块的移动 which cause the plates on the surface to shift.
这些移动触发了火山喷发和地震 - These shifts trigger volcanic eruptions and earthquakes --
与我们生死攸关的事件 events we associate more with death than life.
但这只是短暂的情形 But that's just the short-term view.
从戴安娜的地质学角度 From Diana's geological perspective,
此种从我们星球内部到大气层的物质循环 this cycling of material from the inside of our planet
对生命的进化一直是至关重要的 to the atmosphere has been vital to the evolution of life.
多亏了这个过程 Thanks to this process,
地球的表面温度 the surface temperature of the Earth
没有摇摆得很厉害 has not swung very much,
液态水一直围绕着它 and it has been around that of liquid water
长达数十亿年 for over billions of years.
超级地球更大 Super earths are bigger
所以内部更热 and therefore hotter on the inside.
你开大热量后 And when you turn up the heat,
板块构造就加大了马力 plate tectonics kicks into a higher gear.
那或许就意味着更多的火山喷发 更多的地震 That may mean more volcanoes and more earthquakes.
但同时 星球有了更加稳定的温度 But also,a planet with a much more stable temperature.
在超级地球上 On super earths,
因为对流要快得多 because convection would be much faster,
这种循环可能影响也快得多 - this cycle could respond much quicker --
或许是数量级的加快 perhaps an order of magnitude quicker.
于是我们就可以推测 And then we can speculate
那已经具有了复杂生命进化的可能 that that has enabled the evolution of complex life.
来想想超级地球 Think about how a super earth
将会如何应对抹去了 would have dealt with the impact
恐龙的陨星的撞击的 of the meteorite that wiped out the dinosaurs.
在地球上 这个事件引发了全球性严冬 On Earth,this event triggered an extended global winter
招致了那些冷血巨无霸的灭亡 that spelled the demise of those cold-blooded giants.
然而在更大的星球上 But on a bigger planet,
能够更好地控制其温度 better able to control its temperature,
恐龙或许能幸免于难 dinosaurs might survive
有机会进化出更大的大脑 and have the chance to evolve bigger brains.
但是 生活在巨大版本的地球上 However,there is one major downside
有一个严重的缺陷 to living on a giant version of Earth.
我们地球的核心是一个旋转的液态金属球 The core of our world is a spinning ball of liquid metal
产生出强大的磁场 generating a powerful magnetic field.
该磁场偏转了从太阳发出的危险辐射流 That field deflects a torrent of dangerous radiation from the Sun
构成了一个对这里的所有生命的保护盾 and forms a protective cocoon for all life here.
戴安娜的模型预测 Diana's models predict
超级地球或许就没有这样的力场 that super earths may not have these force fields.
极有可能 lt's very possible
这些行星并没有熔核 that these planets do not have a molten core,
因为其内部压力太大 because their interiors are under so much pressure.
因此 你如果作为生物 So,if you are a creature in a planet
在一颗没有磁场的行星上 that doesn't have a geomagnetic field,
就会一直遭受高能粒子的轰击 you are being bombarded by high-energy particles,
它们会与你的细胞发生作用 and those are interacting with your cells,
引发突变 大概这样 causing mutations,probably.
因此 你就得更加机灵 作为一个有机体 So,you have to be clever,as an organism,
去适应这样的环境 to adapt to those conditions.
何种外星人能够存活在 What kind of alien could survive
浸泡在辐射里的超级地球上呢？ on a radiation-soaked super earth?
它将需要有一个保护壳 lt would need a protective shell,
或许搀和了铅之类的重金属 perhaps laced with heavy metals like lead.
它将会有强大的肢体和锋利的爪子 lt would have powerful limbs and sharp claws
使其在强烈的辐射爆发期间 to let it burrow under the ground
钻入底下 during heavy radiation bursts.
最为重要的是 它将需要 Most important,it would need
有效的基因修复机制 effective genetic repair mechanisms
来修复对其细胞不可避免的辐射伤害 to fix the inevitable radiation damage to its cells.
纯属幻想？ 或许不是 Pure fantasy? Maybe not.
类似的生命形式 Similar life-forms,
虽然小许多 叫做水熊虫 albeit much smaller,called water bears,
存活在地球上滚烫的高辐射地区 survive in boiling-hot,
岩质超级地球的居民 radiation-blasted regions on Earth.
有可能看上去 lnhabitants of rocky super earths
惊人的类似 might look surprisingly familiar.
然而来想象一下一个没有岩石的世界里 But imagine a world where there is no rock,
生物生活在海洋里 and where creatures living in the ocean
以及飞翔在天空中 also fly through the sky.
地球上 On Earth,
进化产生了生命的千变万化 - evolution has produced countless variations on life --
动物潜行水中 animals that glide through the water
翱翔天空 and soar through the sky.
芸芸众生或滑 或爬 或走 或跑 Beings that slither,crawl,walk,and run.
如果其它星球上的生命 lf life on other worlds
遵循我们这里的生命进化模式 follows the evolutionary pattern of life here,
会有其它什么令人费解的特色出现呢？ what other mind-bending features might arise?
好 你有了一颗行星 有了大气层 Okay. So,you got the planet,you've got the atmosphere.
夸张的 Exaggerated.
对 Yeah.
在剑桥市麻省理工学院 At M.l.T. in Cambridge,
天体物理学家萨拉.西格和生物化学家威廉.贝恩斯 astrophysicist Sara Seager and biochemist William Bains
开始想象 are beginning to imagine
这些遥远的星球会是何种模样 what these distant worlds will be like.
大气会出自某处 The atmosphere's gonna come from somewhere,
这样你就有了火山不断产生出大气 so you're gonna have volcanoes producing atmosphere.
他们试图预测行星的大小与成分将如何 They're trying to predict how a planet's size and composition
塑造其生物圈的 will shape its biosphere.
在发现日外行星之前 Before the discovery of ex oplanets,
人们以为所有的行星系 people thought that all planetary systems
都与我们太阳系相像 would be like our solar system.
从那时起 And since that time,
日外行星与日外行星系的发现 discoveries of ex oplanets and ex oplanetary systems
让我们一次又一次的惊讶 have surprised us over and over and over again.
那么 有啥变化呢？ 通通变了 So,what has changed? Everything has changed.
大多数科幻小说假设 Most science fiction assumes
外星人会四处奔走 that aliens are gonna be walking around,
它们要呼吸空气 they're gonna be breathing air.
你知道的 它们登上飞船 You know,they landed a starship,
它们与船长共餐 and they shared dinner with the captain.
你看某些行星环境 You look at some of the planetary environments
外面的 out there,
那是不会发生的 and that is not gonna happen.
那将会是截然不同的 lt's gonna be very different.
最近 萨拉和威廉 Recently,Sara and William
一直在研究GJ 1214b have been studying GJ 1214B,
一颗40光年外的行星 a planet about 40 light-years away
是地球大小的两倍还多 that's more than twice the size of Earth
显示出有大气层的迹象 and shows signs of having an atmosphere.
他俩正致力于发现 Together they are working to discover
1214b云层下方 what it might be like
会是何种情况 to descend beneath the clouds of 1214B.
现在 这个星球 - Now,this planet --
我们无法完全肯定其成分是什么 we're not totally sure what it's made of,
但它有可能是颗水行星 有水蒸气 but it could be a water planet with a steam atmosphere.
根据该行星的温度 And depending on the temperature of the planet,
其液态水与具有水蒸气之间的 the clean division between liquid water
清晰界限可能并不存在 and air with water vapor in it may not exist.
有何种生命可能会出现在 What sort of life could possibly emerge
一个滚烫的蒸汽世界里呢？ on a boiling-hot,steam world?
这个 在地球上 So,on Earth,
此种具有开水和蒸汽的环境 an environment like this with boiling water and steam
会加害于几乎所有的生命 is inimicable to nearly all life.
但是我们正努力去想象一个外星世界 But we're trying to imagine an alien world
在那里 这就是正常的环境 in which this is the normal environment,
我们现在就能够开始模拟一个星球 and we can now start to model a planet
它一片汪洋 that has a huge ocean covering it
然而却是热得要命 and nevertheless is incredibly hot.
那就让我们去思索 That makes us think about,
海洋里会有生命存在么？ "Could there be life in the ocean?
能有化学作用么？ Can the chemistry work?
"如果能 会是何种样子呢？ And if it can,what would it look like?"
DNA这样的分子不会存活在这样的环境中的 A molecule like DNA wouldn't survive these conditions,
但威廉认为 but William believes
更为耐热的遗传物质 more heat-tolerant genetic material
将有可能进化 would likely evolve.
他开始想象 And he's beginning to imagine
能量有可能填写 what entries might fill the pages of a book of life
GJ1214b的生命之书 for GJ1214B.
这颗行星的大气层主要是水 The atmosphere of this planet would be mostly water.
那就是水蒸气 lt would be steam.
它会非常密集 温度很高 lt would be very dense and be very hot.
因此 你一路往下 So,as you go down through it,
你会看到漂浮的植物 会飞的植物生命 you'll find drifting plants,flying plant life,
有一系列生物食用那些植物生命 and a whole range of organisms that eats that plant life.
生物就像是飞鱼 Organisms would be sort of flying fish
或水鸟 这取决于你怎么看待它了 or swimming birds,depending on how you look at it.
它们能够翱翔 So,they'll be able to actually fly through
或畅游在这个区域里 这里仿佛一片大海 or swim through this zone almost as if it was ocean.
地球的海洋产生出了各种生物 Earth's oceans gave rise to creatures of all sizes,
然而深海之王是巨大的滤食动物 - but the kings of the deep are the giant filter feeders --
鲸鱼 whales.
1214b可能也有它们 1214B could have them,too.
因此 我们在这里想象生物 So,the organism we're imagining here
以非常类似的方式活动 works in a very similar way.
它或许具有非常不同的形状 lt might have a very different shape.
然而 它活动在大海里 But it moves through the ocean
然后能够向上进入这个界面区 and then can move up into this interfacial zone.
它们能够长时间呆在界面区里 They can spend much longer in the interfacial zone
行动至很高的地方 就是说 鲸跃 and move much further up into it than,say,a whale breaching
因为密度较大 because the density is greater.
这个水世界是 This aquatic world is a vision
地球可能一直所喜欢的愿景 of what Earth might have been like
虽然它更大 水更多 if it were larger and wetter.
人类无法生存在此地 但生命能找到生路么？ Humans couldn't survive here,but could life find a way?
我们尚…不知道 We don't know...yet.
科学中有许多重要的东西 There are many important things in science,
其中最为重要的一个是想象力 and one of the most important ones is imagination.
因此 至今让人着迷不已的是 - So,what is so fascinating so far --
在日外行星上 物理和化学规律中 in ex oplanets,anything is possible
一切皆有可能 within the laws of physics and chemistry,
我们想象的任何东西都将存在于某处 and anything we imagine will exist somewhere.
出现了水 于是你就能找到生命 Follow the water. There,you'll find life.
那就是天体生物学家想说的话 That's what the astrobiologists like to say.
然而若是没有水呢？ But what if there is no water?
若是行星笼罩在毒气里 What about planets enveloped in to xic air
生命的基本构件 where the building blocks of life
是不是完全不同于我们这里呢？ are completely different from our own?
它们也能够存活么？ Could they also be alive?
生命是顽强的 Life is tenacious.
地球上的角角落落 Everywhere on Earth,
从最冷的大海深处 from the coldest depths of the sea
到沸腾的火山裂隙 to the boiling fissures of volcanoes,
生命都能找到繁衍之道 living things find a way to thrive.
不过外行星的条件 But the conditions on alien planets
可能更极端 could be even more extreme.
我们发现了火与冰的世界 We're discovering worlds of fire and ice,
永久黑夜的世界 worlds of permanent night,
狂风大作 经久不息的世界 worlds where hurricanes are constant and global.
何种外星人能够生活在这些地狱般的地方呢？ What kind of alien could live in these hellish places?
格利泽581d漂浮在距离地球20光年远的 Gliese 581 D floats 20 light-years away from Earth
天秤座里 in the constellation Libra.
它是我们发现有可能有外星生命的 lt's one of the small group of planets we have spotted
少量行星中的一颗 that might harbor alien life.
其红色母星发出的热量 lts red star burns
只有我们太阳的一半 with only half the heat of our Sun,
但因为该行星旋转得很慢 but because the planet spins very slowly,
其一侧要比另一侧热很多 one side is much hotter than the other.
其岩质地面狂风大作 - And its rocky surface is blasted by constant wind --
是放风筝的好地方 a great place to fly a kite.
生物力学专家迈克尔.拉巴贝拉 Biomechanics expert Michael Labarbera
认为格利泽581d上的稠密大气层 believes the thick atmosphere on Gliese 581 D
将其表面笼罩成一片漆黑 would shroud the surface in darkness,
所以生命得攀升寻找亮光 so life would have to climb up in search of light.
他猜想有风筝状的植物攀爬至乌云上方 He imagines kite-shaped plants that rise above the storm clouds
来得到日常所需的太阳能 to get their daily dose of solar energy.
这些风筝植物必须能够进入 These kite plants have to be able to get up
大气层的较高地方 into the higher regions of the atmosphere
以获得足够的采光 in order to get enough light,
它们这样做是为了 and the way they do that is
利用大气层中的切变 to utilize the shear in the atmosphere.
迈克尔的风筝需要两股力量 Michael's kite requires two forces
停留在高空并保持稳定 - to stay aloft and stable --
有风升起风筝 wind to lift the kite,
有锚使其避免一直往上升 and an anchor to keep it from blowing ever upward.
外星风筝植物的动作差不多是同样的道理 The alien kite plant works much the same way.
所以 我们假设这种特殊的植物 So,what we've posited for this particular plant is
上升的一面在绳索的一头 a lifting surface on one end of the string,
而在绳索的另一头 and at the other end of the string,
有东西具有降落伞的功能 something that functions like a parachute
来产生拽力 that produces a drag force.
因为风随着海拔发生变化 And because the wind changes with altitude,
它们的行动表现出不同的速度 they're moving at different speeds.
于是你有了升力来保持风筝的上升 You then get a lift force that keeps the kite up
它被拽拉在减速伞上 and it pulls on the drag chute,
但它保持着绳索的拉力 but that keeps the tension on the string
整个系统是稳定的 and the whole system is stable.
听起来不大可能？ Sounds unlikely?
迈克尔却并不如此认为 Michael doesn't think so.
多年来对地球生物的研究使他相信 Years of studying organisms on Earth has convinced him
生命会进化成适应各种环境 that life would evolve to suit any environment.
进化会通过很奇怪的途径 Evolution goes through very strange pathways
来达到目的地的 to get to an endpoint.
这个特殊的对象 This particular one,
我们在地球上并没有例子 we don't have an example here on Earth,
但是在假设在地球这里 but on the planet posited here
低于地平面的太阳辐射输入 with low solar input for the ground level
和高风切变的星球上 and a high wind shear,
那它就完全有可能起作用的 it's entirely possible that it could function.
靠近格利泽581d表面 Closer to the surface of Gliese 581D,
曾经明亮的阳光黯淡了下去 the once bright sunlight dims
此时这颗日外行星沉浸在了永恒的朦胧暮色之中 as this ex oplanet enters a permanent,hazy twilight.
大气稠密昏暗 The atmosphere is thick and murky,
然而温度足以维持生命 but warm enough to sustain life.
事实上 迈克尔.拉巴贝拉推测 ln fact,Michael Labarbera speculates
它可能拥有一个欣欣向荣的生态系统 that it could host a thriving ecosystem
有猎手与猎物 of hunters and prey.
有何种猎食者会在此进化呢？ What kind of predator would evolve here?
空中猎手 - 薄薄的翅膀 蝙蝠状 An aerial hunter -- thin-winged and bat-like,
却能够像信天翁那样翱翔数日 but able to soar and glide for days like an albatross.
..蝙蝠-天翁？ ...a bat-atross?
这种动物 Now,this animal,
因为大气层相对浑浊 because the atmosphere is relatively opaque,
就必须要能够以最小的付出来长途跋涉 has to be able to travel long distances at minimal cost
以找到它们的猎物 in order to find their prey.
它就有了长长的翅膀 lt's got long wings.
它就有了相对较窄的翅膀 因为更具有效率 lt's got relatively narrow wings because they're more efficient.
它具有相对其身体较大的展翅面积 lt has a big wing area relative to its body.
在地球上 On Earth,
信天翁利用一种叫做动态滑翔的技术 albatrosses use a technique called dynamic soaring
来旅行数千英里 to travel thousands of miles
而几乎不扇动翅膀 while barely flapping their wings.
在长途滑翔中 Gliding in long loops,
蝙蝠-天翁也会节省能量 the bat-atross would also conserve energy
依靠气流携带它前行 by letting air currents carry it along.
该动物实际上所走的距离要许多倍于 The animal actually covers many times the distance
它转圈时所覆盖的面积 in these loops that it's covering on the ground,
但这无关紧要 but it doesn't matter.
它并没有付出什么 那是免费的 lt doesn't cost it anything. lt's free.
其能量的供应来自环境 lt's energy that's supplied by the environment,
并不是机体 not by the organism.
但现在 在一个终日不见阳光的世界里 But how,in a world of permanent twilight,
这个猎手又是如何发现其猎物的呢？ does this hunter find its prey?
在暗无天日中 ln the absence of light,
就得有一些其它办法来寻找猎物了 there's got to be some other way of locating prey.
一个办法就是竖起耳朵静听 One way is just to sit and listen
等待着你的猎物发出声音 and wait for your prey to make noise.
另一个办法就是你弄出声音 The other way is for you to make noise
听回音 - 就是我们所说的声纳 and listen for echoes -- what we call sonar.
就是你发出声波 So that you send a sound beam out
然后等待反射 and you wait for a reflection.
我可以有很多信息 l can get a lot of information
来自球回弹时的反应 from the response of the ball as it comes back.
所以 我把球掷出与它回来之间的延迟 So,the delay between when l throw and when it returns
告诉我目标有多远 tells me how far away the object is.
如果它回来快于我将它扔出去 lf it comes back faster than l threw it out,
那么目标正迎头而来 then the object is coming towards me.
如果它是往另一个方向去的 lf it's going in the other direction,
那它回来就会慢些 it will come back slower.
如果你在寻找猎物 这是个绝妙的主意 lf you're looking for prey,this is a wonderful idea,
当然 除非你的猎物也能够侦测声音 unless your prey,of course,can detect the sound.
蝙蝠-天翁将是一个有效的杀手 The bat-atross would be an effective killer,
所以它的猎物就需要培育有效的防御 so its prey would need to develop effective defenses.
威廉.贝恩斯想象出一种动物 William Bains imagines an animal
类似于一种硬壳海洋生物 similar to the hard-shelled marine life
它早在数亿年前 that evolved on Earth
就已经在地球上进化了 hundreds of millions of years ago.
鹦鹉螺对猎手来说是天然的猎物 The nautilus is natural prey for the hunters,
它们有三重防御机制 and they'll have three defense mechanisms.
首先 当然了 它们有壳 First is,of course,they have a shell.
其次是如果你用声纳来捕猎 The second is if you're being hunted by sonar,
那么你就要发展出很好的耳朵 你才能听到声纳 then you develop very good ears so you can hear sonar.
一旦你听到声纳的回音 你就会奔向它 When you hear the ping of a sonar,you run for it.
它具有一个射流推进系统 And it has a jet propulsion system
这样就能够在紧急情况下将自己往前射出去 that can squirt itself forward in emergencies.
这些家伙将能够 These guys will be able to
将自己射过大气层 jet themselves through the atmosphere
嗖的一下 速度极快 in short bursts,moving very quickly.
所以 到了紧要关头 So,at the last minute,
它们就喷射到一边 逃脱虎口 they'll jet to one side and escape being eaten.
但是尽管有了这些防御 But even with these defenses,
蝙蝠-天翁仍将是可怕的对手 the bat-atross would be a fearsome opponent,
鹦鹉螺不会一直逃之夭夭的 and the nautilus won't always get away.
它命悬一线 lt's life on the edge.
始终有顶级的猎食者 There always is a top predator.
它是最稀有的动物 lt's the rarest animal,
但它并不是你想狭路相逢的家伙 but it's not the guy you want to meet in a dark alley.
冷酷的环境滋生冷酷的生命形式 Brutal conditions breed brutal life-forms.
在地球这里 经过了数亿年 Here on Earth,over hundreds of millions of years,
数十亿钟生物为竞争求生 billions of different creatures competed for survival,
但最终 突变让一种动物 but eventually,a special mutation enabled one animal
成为了星球上至高无上的猎食者 to become the planet's top predator.
那个突变就是人的大脑 That mutation was the human brain.
在太空中某处 Somewhere out in space,
外星演化也应该将人类打造成 alien evolution should have created beings
至少如我们这样聪慧 at least as smart as we are.
智能外星人究竟是何模样呢？ What do intelligent extraterrestrials look like?
此人认为他知道 This man thinks he knows,
答案可能对地球生命是个坏消息 and the answer could be bad news for life on Earth.
随着每一个新世界被我们发现 With each new world we discover,
我们都更进一步接近发现 we come one step closer to finding evidence
地球以外生命的证据 of life beyond Earth
甚至实现 and perhaps to fulfilling our dreams
我们与外星生命形式沟通之梦 of communicating with alien life-forms.
但一旦那天到来 But if that day ever comes,
我们最好防患于未然 we'd better brace ourselves for a shock,
因为许多科学家认为 because many scientists think
它们有可能根本就不像芸芸众生 they may not look like living beings at all.
过去50年里 For the past 50 years,
搜寻外星智能 （SETI） the search for extra-terrestrial intelligence,SETl,
试图捕捉到任何一丝 has attempted to capture any glimmer of communication
来自外星世界的信息 from alien worlds.
对于赛斯.肖斯坦克 这位SETI资深天文学家来说 For Seth Shostack,SETl's senior astronomer,
它就是搜寻我们遥远的宇宙图像 it's a search for our distant cosmic image,
搜寻具有与我们一样聪慧大脑的物种 for a species with a brain at least as smart as ours.
说到智能生命 When it comes to intelligent life,
我们还没有发现它 we haven't found it.
所以对此是说什么的都有 So,there are people on all sides of the issue.
但是有一件事可以说服你 - But the one thing that can convince you --
我认为可以说服任何人 - 那就是即使你认为 l think can convince anybody -- is that even if you think
可以导致生命的过程 the processes that could lead to life,
导致智能生命的过程 lead to intelligent life,
是不会经常发生的 are not going to occur very often,
不会有许多机会使其发生在宇宙间 there's so many chances for it to happen in the cosmos,
如果我们是唯一具有智能生命的世界 it would be miraculous
那将是一个奇迹 if we were the only world with intelligent beings.
人类不是地球上最大 Humans aren't the largest
或最快 or the fastest
或最敏捷的动物 or the most agile animals on Earth,
但我们是最聪慧的 but we are the smartest.
我们的大脑置我们于顶部 Our brains have put us on top.
但是 依然有很多改进的余地 There is,however,plenty of room for improvement.
有一个不可避免的趋势 就是认为 There's an unavoidable tendency to think
我们好像就是万物之灵 that we're kind of the crown of creation.
正是这样 This is it.
你知道 40亿年的进化 You know,4 billion years of evolution
从生命之处到我们 from the beginnings of life to us.
你知道 我觉得你要是去问恐龙 You know,l think if you asked the dinosaurs
同样的问题 - the same question --
你是否认为你就是万物之灵呢？ "Do you think you're the crown of creation?"
我打赌它们会说 没错 l bet they would have said "Yes,"
如果它们能够开口的话 if they could have talked.
正是这样 这就是进化的终点 "This is it. This is the end of evolution."
啊 它们大错特错了 Well,they were wrong.
我们认为我们是进化的终点 And it would be wrong for us to think
同样错了 显而易见 we're the end of evolution,too,obviously.
那么 进化下一步会将我们带往何处呢？ So,where will evolution take us next?
哪里有可能已经出现了外星文明了呢？ And where is it likely to have taken alien civilizations?
赛斯认为我们需要看一下电脑来寻求答案 Seth thinks we need to look at our computers for the answer.
从上世纪70年代起 Since the 1970s,
当时软盘是铁定的标准 when floppy disks were the gold standard,
这个速度在处理指令的电脑上 this speed at which computers process instructions
已经提高了10万多倍 has increased more than 100,000 times.
如今 花上1000美元 你能够买到的电脑 Today,for $1,000,you can buy a computer
可以这么说 其思维能力 - that has,if you will,the thinking capability --
至少是一只蜥蜴的计算能力了 or at least the computational capability of a lizard.
并非那么有趣 Not so interesting.
但是到了2020年或2025年 1000美元能卖给你的笔记本 But by 2020 or 2025,$1,000 will buy you a laptop
将会具有与人脑相同的计算能力 that has the same computational power as a human brain.
人工大脑的智商 The lQs of artificial brains
从0发展到200 are going from zero to 200
只走过了历史的瞬间 in the historic blink of an eye.
类似的轨迹在一颗星球上是如何表现 How would a similar trajectory play out
在我们面前只有500年呢？ on a planet that is a mere 500 years ahead of us?
关于人工智能的有趣之处 The interesting thing about artificial intelligence,
当然就是它的进化步伐 of course,is its pace of evolution.
我是说 我们恪守达尔文的进化论 l mean,we're stuck with Darwinian evolution,
但机器却不会 but the machines wouldn't be.
这意味着如果你要开发思维机器 What it means is that if you develop a thinking machine,
它将会自我提升得非常非常快 it's going to improve itself very,very quickly.
1948年 数学家约翰.冯.诺依曼 ln 1948,mathematician John Von Neumann
料定机器会非常聪慧 imagined a machine so intelligent
它能够复制自我 it could make copies of itself.
每个副本都会对原先的模型进行改进 Each copy would improve on the previous model,
就好比大自然在不断改进其设计 much as nature continually improves on its designs.
但是这种机器的进化将会发生得 But this machine's evolution would take place much faster
比生物进化快许多 than biological evolution.
如今 冯.诺依曼机器以原生态存在着 Today,Von Neumann machines exist in crude form.
在比我们这里发达的星球上 On a planet more advanced than our own,
它们是否可能会是最智慧的生命形式 could they be the most intelligent life-form,
占统治地位的生命形式么？ the dominant life-form?
我们的首次接触是否会是 Will our first contact be
超级智能机器间的竞赛呢？ with a race of super-intelligent machines?
你只会听到来自 You're only gonna hear from a species
至少聪慧如我们的物种的声音 that's at least as clever as we are.
那么 有可能它们在50到100年里处于 So,what are the odds that they're within 50 or 100 years
我们的发展水平么？ of our level of development?
相当渺茫 Pretty slim.
它们有可能在上万 数百万 They're likely to be thousands,millions,
甚至更多年领先于我们 maybe even more years ahead of us.
所以 你若是思量片刻 So,if you think about that for a moment,
你就会承认如果我们发现了信号 you recognize that if we do find a signal,
运气太好了 the odds are pretty good
那信号是来自人工智能 that that signal's coming from artificial intelligence,
而不是那些柔弱的 丑不拉几的长着大眼睛的小家伙 not some soft,squishy,little gray guy with big eyeballs.
在一些遥远的行星上 On some distant planet,
生命之书可能已不再包括任何生命形式了 the book of life may no longer contain any biological forms.
如果机械生命已足够强大 And if mechanical life has enough power,
那么就已不再限制它能够变得有多大和多复杂了 there's no limit to how large or complex it can become.
或许它们已自我改组了 Or maybe they've reorganized themselves
以至于它们能够在许多物种成员中 so that they can share the thinking load
分享思想负担了 amongst many members of the species,
好比是计算机的分布处理 like distributed processing with computers.
我的意思是 外星人为什么要满足于 l mean,why should the aliens be content
局限在刚好能够装进 to be stuck with a kind of intelligence
它们头脑的那种智能呢？ that can fit inside their heads?
外星进化 Alien evolution
可以产生出充满生机的机器星球 could produce a living machine planet
脉动着数十亿个外星人头脑 throbbing with the combined intelligence
所组合起来的智慧 of billions of alien minds.
如果如此发达的生命存在 那我们怎么会认出它呢？ lf such advanced life exists,how would we spot it?
我们究竟该咋办呢？ And should we even want to?
外星人会当朋友欢迎我们么 Will aliens welcome us as friends
还是视我们为威胁呢？ or view us as threats?
抑或视地球为征服之地呢？ Or perhaps see Earth as a world to conquer?
我们搞不清楚外星人的模样 We wonder what aliens look like,
但我们对它们的模样又是什么呢？ but what do we look like to them?
这个女人已经将她自己放进了它们的头脑 This woman has put herself inside their heads,
她认为她已经有了答案 and she believes she has the answer.
人类只要仰望夜空 As long as humans have looked up at the night sky,
就想知道外面是否有什么或有谁 we have wondered whether something or someone out there
在回看 is looking back.
我们想知道外星人是何模样 We want to know what aliens look like.
我们又是何模样对外星人的呢？ What do we look like to aliens?
如果有智能生命在那里 lf there is intelligent life out there,
地球是否貌似值得一游的地方呢？ does the Earth look like a place worth visiting?
2008年5月29日 May 29,2008.
太空3100万英里处 31 million miles out in space,
一个科技发达种族的眼睛 the eyes of a technologically advanced race
扫描我们的星球寻找生命的签名 scan our planet for the signatures of life.
不是外星人 但这仍然是非同寻常的 Not aliens,but this was still a close encounter
近距离接触 of an extraordinary kind.
它是航天局的太空探测器 EPOXI lt was the NASA space probe Epo xi.
发送回彗星的特写 Sent out to get closeups of comets,
EPOXI短暂将镜头对准了它的母星 Epo xi briefly turned its lens back to its mother planet.
第一遭 And for the first time,
我们看地球就如外星人可能看我们那样 we saw the Earth as aliens might see us.
天体物理学家萨拉.西格是EPOXI小组的一员 Astrophysicist Sara Seager was part of the Epo xi team.
萨拉平时研究日外行星 Sara normally studies ex oplanets,
搜寻外星大气层 looking for clues
和生态系统的线索 about alien atmospheres and ecosystems.
EPOXI探测器给了她机会去发现 The Epo xi probe gave her the chance to find out
地球给外星天文学家可能的模样 what Earth might look like to an alien astronomer.
如果你假装你对地球一无所知 lf you pretend you know nothing about Earth,
那你将如何去认识地球呢？ what could you learn about Earth?
外星人可能会分辨出地球的自转速度 An alien would be able to pick out Earth's rotation rate.
它们可能会注意 They would be able to notice
我们具有极有差异的反射面 - that we have surfaces of very different reflectivity --
那是云层 陆地及海洋 that's cloud,land,and ocean.
它们还能看到我们有天气 And they could also see that we have weather.
它们会看到的变化 They would see variability
与地球自转速度无关 that isn't related to the rotation rate of Earth.
EPOXI所做的第二件事是观察地球的光谱 - The second thing Epo xi did was look at a spectrum of Earth --
那就是 取白光 that is,take the white light
将其劈成各种颜色 and split it up into the different colors
来检视是否有什么颜色不见了 and to check and see if any of those colors were missing.
我们称其为光谱 We call that a spectrum.
地球颜色的频谱 The spectrum of Earth's colors
就像是一面旗帜 are like a flag
宣布了我们星球上存在有生命 announcing the presence of life on our planet.
大海之蓝 云层之白 The blue of the oceans,the white of the clouds,
大地之绿 the green of the land
全都是生机勃勃的生态系统的标记 are all markers of an active ecosystem.
如果一个外星人从远处眺望我们 lf an alien is looking back at us from far away,
外星人会看到 the aliens would see
我们大气层里有氧 that we have o xygen in the atmosphere.
事实上 我们的大气层里有20%的氧气量 ln fact,our atmosphere has 20% o xygen by volume.
迷人之处就在于 没有生命 What's so fascinating is that,without life,
我们的地球基本上就要少100亿倍的氧 our Earth would have basically 10 billion times less o xygen.
这样一来 氧气就基本上在地球上不存在了 So,o xygen would be essentially non-existent on Earth.
地球上的氧来源于生命 And o xygen on Earth is created by life,
所以那些外星人就会知道如此大量的氧 so those aliens would know that o xygen in such large quantities
不应该存在于我们的大气层里 should not be in our atmosphere
除非源源不断来源于什么东西 unless it is being continually produced by something.
我们从地球物理学知道没有什么 And nothing that we know of in geophysics
能够产生出如此多的氧气 can produce so much o xygen.
那就是为什么我们将其归属于生命 And that's why we attribute it to life.
外星人可能看到我们的星球支持生命 Aliens might see that our planet supports life,
但它们或许没有看到 but they might not see
地球是科技先进的 that Earth is technologically advanced.
它们得仔细观观察 They would have to look carefully
进行检测 诸如大气污染 to detect things like atmospheric pollution
或我们城市的热特征 or the heat signatures of our cities.
读取我们星球以及 Reading the colors of our world
宇宙间数以百万计的类似的其它星球的颜色 and the millions of others like it out in the Universe
对先进的外星文明来说易如反掌 would be easy for an advanced alien civilization.
不幸的是 这对我们来说还不是很容易 Unfortunately,it is not yet easy for us.
找出日外行星 Spotting ex oplanets
推动了目前科技的限制 pushes the limits of current technology.
如果我们想看到颜色 我们就需要一套新的手段 lf we want to see colors,we need a new set of tools.
天体物理学家迪米塔.萨瑟罗夫 Astrophysicist Dimitar Sasselov
想做点那方面的事情 wants to do something about that.
这些是小圆行星 These are little round planets.
我要投下几颗来表示凌日行星 l'm gonna just drop a few on to show transiting planets.
我猜有两颗凌日 l guess there's two transiting.
迪米塔的太太希拉画的深太空场景 Dimitar's wife,Sheila,paints scenes of deep space
灵感来自他对开普勒行星探测器的研究 inspired by his research on the Kepler planet-finding probe.
这就是我们想用开普勒去探索的东西 This is the kind of thing we want to discover with Kepler.
有凌日行星 有一个卫星围绕着它 A transiting planet,and there is a moon around it.
那就太好了 That would be great.
这就是 So,there it is.
那就是载有生命的行星 - 就在这里 That's the planet with life on it -- right here.
我们有个大问题 We have a big problem.
这个挑战涉及到我们无法分开测量 This challenge relates to our inability to measure
恒星与行星的颜色 the colors of the star or the planets separately
到极高的精度 to very high precision.
面临的是10到100倍的挑战 And the challenge is about the factor of 10 to 100
超越了当前科技水平 beyond what current technology works.
我们最大的障碍 The biggest barrier we have
是观察其它行星颜色时 to seeing the colors of other planets
每个摄影师都会遇到的情况 - is something every photographer has run into --
相机抖动 camera shake.
如果你要拍摄黑暗中的图像 lf you take a picture in the dark,
你就需要有尽可能多的光 you need as much light as possible,
这就意味着你无法挪动相机 which means you can't move the camera
即你会获得模糊的图像 or you'll get a blurry image.
类地行星非常小 极其遥远 Earth-like planets are so small and so far away
它们的图像只够得上数码相机单个像素的 that their images only fill one thousandth of a single pixel
千分之一 of a digital camera.
如果那个像素稍有移动 lf that pixel moves even slightly,
相机抖动将会破坏相片 the camera shake will ruin the picture.
但是你又如何能够保持一个像素完全静止 But how can you possibly keep one pixel perfectly still
数日乃至数年 over the days and years it takes
来跟踪遥远太空里的对象呢？ to track an object in distant space?
迪米塔的解决方案是太空激光梳滤波器（Astro-comb） Dimitar's solution is the astro-comb.
它利用激光维持望远镜的相机传感器 lt uses lasers to keep a telescope's camera sensor
在几十年间的精确校准 precisely calibrated over a period of decades.
你这里所看到的astro-comb The astro-comb that you see here
是个技术突破 is the technological breakthrough
用来弥补那个不足 which was needed to bridge that gap.
一旦我们看到了其它星球的真正本色 When we see the true colors of other worlds,
我们就将会知道在整个宇宙间生命在哪里 we will know where and how life is distributed
又是如何分布的 across the Universe.
我们寻求外星生命的下一个阶段就即将开始 And the next phase of our quest for alien life will begin.
它将把我们带向何方？ Where will it take us?
何种刺激的新世界将被我们发现呢？ What exciting,new worlds will we see?
何种新的意想不到的生物会居住在上面呢？ What new and unexpected creatures might live on them?
生物学家认为那里的生命可能看上去类似地球上的 Biologists think that life out there might look earth-like,
但它看上去不会是人类 but it won't look human.
外面有如此多的行星 生命有如此多的机会 With so many planets out there,so many chances at life,
我们可能有类人的亲属在遥远的地球上 we could have human-like relatives on a far-away earth.
类似我们这样的生物 Creatures like us,
或许如我们这样急于了解 perhaps as anxious as we are to know
它们在宇宙间是否是孤独的 if they are alone in the Universe.
随着我们手段的改进 我们发现它们的机会也增大了 As our tools improve,so do our odds of finding them.
显然我们已经进入了 lt is clear that we're in a new age
探索与发现的新纪元 of exploration and discovery.
500年来 lt hasn't been for 500 years
人类一直试图寻找 that people have tried to discover planets
围绕其它恒星的行星 around other stars.
现在我们发现了它们 Now we have them.
我们还有更多的探索 好事还在后头呢 We have much more to explore,and the best is yet to come.
1000年后 1,000 years from now,
人们回顾我们这代人时会问 when people look back at our generation and ask,
最大的成就是什么？ "What are the biggest accomplishments?"
我觉得这些人开展星际旅行 l like to think of these people making interstellar journeys
回头一想 and looking back and thinking
我们就是开始这一切的人 we were the ones who started it all.
外星人究竟是何模样？ What do aliens look like?
我们想象力的极限在哪里？ What are the limits of our imagination?
外星人真正面目 The true face of an alien
可能会无视我们的科学猜测 will probably defy our scientific speculations.
但我们的努力不会白费 But our efforts won't be wasted,
即使我们所得到的所有细节都是错误的 even if we do get all the details wrong.
我们关于外星生命的永恒好奇 Our eternal intrigue about alien life
我们对它的持久恐惧 and our persistent fear of it
全都出自同一个源头 - both rise from the same source --
寻求了解 the quest to understand our place
我们在宇宙的生命大家族里所处的位置 in the family of life-forms that populate the cosmos.
知道了那个 Know that,
我们就会知道人类的命运 and we'll know the destiny of humankind.