人固有一死吗 Must we die?
宇宙中是否会有永恒的生命 Are there beings in the cosmos who live forever...
在时间的长河中 afloat on an endless journey
无尽地漂流 down the river of time?
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翻译 令狐伟
翻译 小小SU
时间轴 新之助
后期 吉吉
校对/总监 OBAFGKM
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宇宙
时空之旅
我们的祖先通过日月星辰的变化 Our ancestors marked the passage of time
来标记时间的轮转 by the Moon and Stars.
直到5000年前 But it was the people who once lived here,
居住在这里的人 around 5,000 years ago,
首次以小时和分钟为单位 who first starting chopping up time
将时间分割为一段一段的小块 into smaller bite-sized portions of hours and minutes.
他们称这里为乌鲁克 They call this place Uruk.
我们叫它伊拉克 We call it Iraq.
这块土地是美索不达米亚的一部分 It's a part of Mesopotamia,
位于底格里斯河和幼发拉底河之间 the land between the Tigris and the Euphrates rivers.
城市的概念由此而起 The city was invented here.
这是人类在和时间无休止的抗争中 And one of humanity's greatest victories was won
诸多伟大成就之一 in the ceaseless battle against time.
我们在这里学会了书写文字 It was here that we learned how to write.
死亡再也不能让我们沉默 Death could no longer silence us.
写作给了我们力量 And writing gave us the power
令我们可以穿越时光 to reach across the millennia
和数千年后的人交谈 and speak inside the heads of the living.
在历史的长河中 No one has ever spoken
没人可以比这位阿卡德的公主 across a longer stretch of time's river
跨越更长的时间 than this Akkadian princess,
她就是史上第一位帝王的女儿 daughter of the first emperor in history,
月亮女祭司 恩黑杜安娜 and priestess of the Moon-- Enheduanna.
她不仅会写诗 For not only did she write poetry,
还做了一些 but Enheduanna did something
前无古人的事情 no one before her had ever done--
她为自己的作品署了名 she signed her name to her work.
她是第一个 She's the first person for whom
让后人知晓她的名字 we can say we know who she was,
以及梦想的人 and what she dreamed.
她梦想着穿过奇迹之门 She dreamt of stepping through the Gate of Wonder.
以下这段是她的心声 Here's a thought Enheduanna sent
穿越了4000年入你耳中 across more than 4,000 years to you.
取自于她的一篇作品 It's from her work entitled
名为 《最勇敢之女士》 Lady of the Largest Heart.
伊南娜 金星守护者 Innana, the planet Venus,
爱之女神 goddess of love,
您的丰功伟业 will have a great destiny
将名扬寰宇 throughout the entire universe.
名扬寰宇 ...throughout the entire universe.
乌鲁克还是《英雄的旅程》 And Uruk is also the place where the epic tale of
这部史诗巨作的诞生地 "The Hero's Journey" was first written down.
在蜘蛛侠 天行者卢克 Before Batman, Luke Skywalker,
奥德修斯之前 在所有英雄之前 Odysseus-- before them all--
有个叫吉尔伽美什的人 there was a man named Gilgamesh
他离开家乡去寻求征服时间的方法 who left home on a quest to vanquish time.
吉尔伽美什不懈地寻找永生的方法 Gilgamesh was searching for immortality.
他四处游历 He looked everywhere,
获取智慧 gained complete wisdom,
破解谜团 uncovered what was hidden.
他带回了灭世洪水前的故事 He brought back a tale of times before the Great Flood.
他建造了乌鲁克城墙 He built the Wall of Uruk,
再无君王可以匹及 which no future king will ever match.
纵观吉尔伽美什的一生 Read the story of that man Gilgamesh,
这位出生在乌鲁克的英雄 a hero born of Uruk,
他历经百般磨练 who went through all kinds of sufferings.
穿越汪洋 Who crossed the ocean,
跨过大海 直到日出之地 the broad seas, as far as the sunrise;
他走遍天涯海角 who inspected the edges of the world,
只为寻求永生 searching for eternal life.
在途中 On his travels,
吉尔伽美什遇到一位智者 Gilgamesh encountered a wise man
乌塔那匹兹姆 named Utnapishtim,
他告诉吉尔伽美什一场洪水将曾经毁灭世界 who told him the story of a flood that destroyed the world,
但一位天神指引了乌塔那匹兹姆 and how one of the gods instructed Utnapishtim
建造出方舟来拯救家人和动物 to build an ark to rescue his family and the animals.
关于洪水浩劫的最初记载 The earliest surviving account of the flood legend
出现于美索不达米亚 was written down in Mesopotamia,
一千年后这个故事被转述 a thousand years before it was retold
即《旧约》里的诺亚方舟 as the story of Noah in the Old Testament.
所以 吉尔伽美什算得上 So, you could say Gilgamesh
达成了他追求永生的夙愿 fulfilled his quest for immortality.
我们依旧阅读讲述吉尔伽美什的史诗 We still read the Epic of Gilgamesh,
在每位读者心中 他都得以重生 and with every reader he lives again.
之后又出现了一代又一代的超级英雄 And all those heroes and superheroes who have come since
追随着首位英雄的足迹 follow in the footsteps of the first hero's journey--
这也是一种永生的体现 another kind of immortality;
英雄的故事在各个文明中前后传承 a story sent from one civilization to another
跨越千年而不息 across thousands of years.
但生命本身的故事 But life itself sends its own stories
却可以跨越数十亿年 across billions of years.
我们每个人的体内都携带着一条信息 It's a message that every one of us carries inside,
它通过一种所有地球生命可以读懂的语言 inscribed in all the cells of our bodies,
存在于我们体内的每一个细胞 in a language that all life on Earth can read.
基因序列的字母表 The genetic code is written in an alphabet
仅包含四个字母 consisting of only four letters.
每个字母都是一个由原子构成的分子 Each letter is a molecule made of atoms;
每个单词都只有三个字母 each word is three letters long.
每个生命都是一件杰作 Every living thing is a masterpiece,
由自然写就 通过进化完善 written by nature and edited by evolution;
是一本如何维持和复制 the instructions for running and reproducing
复杂生命的说明书 the intricate machinery of life.
生命的基本信息 The essential message of life
被复制和再复制了三十亿年 has been copied and recopied for more than 3 billion years.
但这信息是如何产生的 But where did that message come from?
无人知晓 Nobody knows.
也许它源于一个像这样被光照射的小水坑 Perhaps it began in a shallow, sunlit pool, just like this.
出于某种原因 富碳分子 Somehow, carbon-rich molecules
开始通过耗能来进行最原始的自我复制 began using energy to make crude copies of themselves.
一部分分子复制能力很强 Some varieties were better at making copies,
后代也就更多 and left more offspring.
竞相复制的分子自身结构愈发复杂 The competing molecules became more elaborate.
生命自身已然处于进化之中 Evolution and life itself was underway.
或许生命是在 Or life could've started
深海海床的火山口处 in the searing heat of a volcanic vent
悄然而生的 on the deep sea floor.
亦或是在宇宙中漂流数载 Or is it possible that life came to Earth
来到地球的 as a hitchhiker?
我来给你讲一个 Let me tell you a story
关于异星来客的故事 about a traveler from another world.
那喀拉是一个位于埃及亚历山大港附近的村庄 The peace of the Egyptian village of Nakhla, near Alexandria,
1911年6月的一个清晨 was abruptly shattered
这里的平静被突然打破 on a June morning in 1911.
陨石上的信息 Written in this meteorite
显然来自于另一个星球 was a message from another planet.
但此后的70年里 But 70 years would pass
却无人可以解读它 before anyone could read it.
直到1976年 In 1976,
两艘美国宇航局的 NASA landed two
维京号宇宙飞船在火星成功着陆 Viking spacecraft on Mars.
卡尔·萨根带领我们 Carl Sagan took us there
完成了人类首次宇宙旅行 on our original journey through the cosmos.
我们发现火星上空气的密度 We found that the Martian air
低于地球的百分之一 was less than one percent as dense as ours,
而且基本由二氧化碳组成 and made mostly of carbon dioxide.
只有少量的氮气 There were smaller amounts of nitrogen,
氩气 水蒸气和氧气 argon, water vapor and oxygen.
几年后 A few years later,
当科学家开始分析 when scientists thought to analyze the gasses
那喀拉陨石
那喀拉陨石内部的气体 trapped inside the Nakhla meteorite,
和类似陨石的气体组成时 and other members of its class,
火星大气
他们发现了惊人的相似性 they found a striking similarity--
绝大多数陨石 the vast majority of meteorites
都是其他行星的碎片 are fragments of asteroids.
但坠落在那喀拉的陨石 But the kind that hit Nakhla, on Earth,
却只能来自一个星球 could only have come from one place...
火星 Mars.
欢迎来到火星 Welcome to Mars.
十亿多年前 这里的一处火山爆发 Over a billion years ago, a volcano erupted here
熔岩冷却后形成了坚硬的岩石 and its lava cooled into solid rock.
数亿年过后 Hundreds of millions of years later,
这片区域被洪水冲刷 this area was flooded with water.
洪水过后很久 And long after that flood,
一块直布罗陀巨岩般大小的小行星 an asteroid the size of the Rock of Gibraltar
撞到了火星表面 crashed into the Martian surface,
炸出来一个巨大的火山坑 blasting out a huge crater.
很多碎片被抛回太空 Much of the debris was ejected back out into space,
围绕太阳旋转 where it orbited the Sun until
直到来自母星球火星的引力扰动 a gravitational tug from its home planet, Mars,
将其中的一块巨岩 diverted one of the boulders
偏转到能和地球碰撞的轨道 into a collision course with Earth.
它的到来令小小的那喀拉为之震惊 Its arrival shook up the little village of Nakhla.
如果把太阳系比作一个交通系统 Meteorites of the type that hit Nakhla
那撞击那喀拉的陨石就好比系统里的交通工具 are the vehicles of a natural interplanetary transit system
在各个行星之间运送岩石 that sends rocks between the planets.
这样的陨石好似一艘微生物的救生船 Such a meteorite can safely shelter microscopic cargo--
承载了生命的种子 the seeds of life--
如同一艘行星际方舟 an interplanetary ark.
许多岩石是多孔的 带有很多藏身之所 Most rocks are porous, full of tiny nooks and crannies,
让生命有搭便车的机会 where life can stow away.
我们知道一些细菌可以在 We know that some microbes can survive
恶劣的宇宙环境下存活 the hostile environment of space.
以这些细菌为例 Take these guys, for instance.
它们在国际空间站的外表面 These microbes spent a year and a half
生活了一年半之久 riding on the outside of the International Space Station,
暴露在宇宙的极端温度 真空 exposed to the extreme temperatures, vacuum,
以及太空辐射之中 and radiation of space.
当它们被带回地球时 And some of them were still alive and kicking
其中一些依旧生命力旺盛 when they were brought back to Earth.
更令人惊讶的是这些细菌 Even more astonishing are these creatures,
竟然在八百万年死寂般的沉睡后苏醒 awakened from a deathlike sleep of eight million years.
它们在南极大陆冰封了数百万年 They were frozen in the Antarctic ice millions of years
那时我们人类还不存在 before our species even existed.
而它们却仍然活着 And they're still alive.
如果生命可以抵御宇宙的严酷 If life can withstand the hardships of space
忍耐数百万年 and endure for millennia,
那它一定可以搭乘天然的星际旅行系统 then it could ride the natural interplanetary transit system
在各个行星间穿梭 from world to world.
可以大胆猜测我们的微生物祖先 It's a good bet that our microbial ancestors
在宇宙中漂流了很久 spent some time in space.
为什么这么说呢 Why do we think so?
地球的年龄是四十五亿年 The Earth is four-and-a-half- billion-years old.
在它的前半生里 For the first half of its lifetime,
巨大的小行星每隔几百万年 large asteroids were bombarding the planet
就要光临一次 every few million years.
最为强烈的几次撞击将海洋汽化 The most violent impacts vaporized the oceans
甚至融化了地表的岩石 and even melted the surface rock.
每次这样的撞击 Each such collision
都会让地球上的细菌 would have completely sterilized the planet
灭绝几千年 for thousands of years.
但我们通过分析化石得知 But we know from fossils in the rocks
在地球的形成期内 that bacteria were evolving on Earth
细菌也在进行着进化 during this formative period.
那它们是如何在这样的条件下得以存活呢 So how could life have survived such a lethal series of blows?
只要当体积较大的小行星撞击地球时 Whenever one of those big asteroids hit the Earth,
爆炸都会形成一个陨石坑 the explosion would blast out a crater,
同时将数百万块碎片发射回宇宙 launching millions of boulders into space.
许多碎片的内部都携带了细菌 Many of those rocks carried living bacteria inside.
其中的一些在宇宙中存活下来 Some of the bugs would have survived in space,
留在地球上的细菌因高温灭绝 while all those left behind on Earth would have been fried.
每次撞击后的数百年 A few thousand years after each impact,
地球将逐渐冷却 the Earth would have cooled down enough
直到足以将水蒸气凝结成海洋 for water to condense into oceans.
整个地球将重新可供居住 The planet would again be habitable.
同时 那些被发射到宇宙中的碎片 Meanwhile, most of the rocks launched into space
将围绕太阳旋转 would have been orbiting the Sun.
其中一些将重新和地球相遇 Some of them would encounter the Earth again,
穿过大气成为陨石 reenter the atmosphere as meteorites,
把珍贵的细菌带回地球 and deliver their precious cargo of life
再次生根发芽 to re-seed the planet...
好比诺亚方舟 like Noah's ark.
这将意味着生命的进化 What this means is that life doesn't have to
不必在每次灾难后推倒重来 start over again from scratch after each catastrophe.
它可以哪里跌倒哪里爬起来 It can pick up where it left off.
当太阳系还很年轻时 When the solar system was young,
金星和地球十分相似 Venus was probably more like Earth,
拥有大海 甚至生命 with oceans and maybe even life.
金星 地球和火星通过小行星的撞击 Venus, Earth, and Mars were all exchanging rocks
彼此交换岩石碎片 with each other, due to asteroid impacts.
地球上的生命会携带 Does life on Earth carry any traces
远古时期星际旅行时留下的痕迹吗 of interplanetary voyages made in the distant past?
为什么有些细菌可以在 Why is it that some microbes can survive
辐射强烈和真空的宇宙环境下存活 the intense radiation and vacuum of space?
地球上没有这些条件 These conditions don't naturally exist on Earth.
也许这些细菌正在告知我们 Maybe those bugs are telling us
它们的祖先在几十亿年前的宇宙中经历了 that their ancestors survived those same conditions in space,
同样的环境 a few billion years ago.
现在我们知道了细菌可以隐蔽在岩石中 So we know that microbes can stow away in rocks
在行星际旅行中存活下来 and survive the voyage from planet to planet.
那么它们在恒星之间的旅行又是怎样的呢 But what about trip from star to star--
会是一场恒星际冒险之旅么 an interstellar odyssey?
这是蒲公英 The dandelion.
大约三千万年前 Around 30 million years ago,
它进化出另外一种方式 it evolved another way to send its own message of life
在时空中传递生命的信息 through space and time.
它的每粒种子都像一个伞兵 Each seedling is a little paratrooper,
随风飘荡 floating on the wind,
踏上冒险之旅只为寻找安全的着陆地点 risking everything for a safe place to land.
上升气流可以把它们带向空中 Updrafts can carry them higher into the air.
一只蒲公英可以飞行几十 A dandelion can travel dozens,
乃至数百千米的距离 possibly hundreds of kilometers,
甚至可以飞越山脉 even crossing over mountain ranges.
进化使蒲公英变成一只精巧的飞行器 Evolution has shaped it into an exquisite flying machine.
它的种子也算是一种方舟 The seed is another kind or ark,
通过驾驭流动的空气 ensuring the survival of its species
从而来到安全的地方得以存活 by riding the currents of the atmosphere to safe harbors.
每粒种子的DNA都带着一个故事 Each seed in its DNA carries a story,
讲述了下一个蒲公英的特征和命运 the character and destiny of the next dandelion--
生命就在这样的故事中代代相传 life propagates by retelling its story.
生命能够在恒星之间的旅行中 Is it possible that life could survive the journey
幸存下来吗 from star to star?
恒星之间的距离一百万倍于 The stars are about a million times farther apart from each other
行星之间的距离 than are the planets.
宇宙如此浩瀚 Space is so vast
以至于一颗地球上抛射出去岩石 that it would take billions of years
要花费数十亿年的时间 for a rock ejected from the Earth
才能和另一颗恒星的行星相撞 to collide with a planet circling another star.
在如此长时间的宇宙辐射下 Any stowaway microbes would never survive
隐匿在岩石上的细菌根本无法存活 the cosmic radiation for that long.
但还是存在一套可能的理论 But there's a plausible scenario
证明生命能在不同的恒星系统间传播 for how life could spread from one solar system to another.
数千万颗恒星在引力作用下 The stars of the Milky Way are drawn by gravity
沿巨大的轨道绕银河系中心旋转 in their own enormous orbits around its center.
例如太阳 Our Sun, for example,
公转一圈 takes some 225 million years
要两亿两千五百万年 to complete a single orbit.
太阳系每绕银河转一圈 During each revolution around the galaxy,
就会穿过两到三个 our solar system will pass through two or three
巨大的星云 gigantic interstellar clouds,
每个星云都跨越了数光年 each of them many light years across.
银河系就是创世机器 Galaxies are world-making machines.
我们的银河系里有一百多个这样的巨大星云 Our Milky Way has more than 100 of these vast clouds,
气体和尘埃在这里集聚 a place where gas and dust condense
形成新的恒星和行星 to form new stars and planets.
在穿越银河系的旅程中 In its travels through the Milky Way,
太阳不仅被自己的行星环绕 our Sun is accompanied not only by its planets,
同时还有一万亿彗星远远相随 but also by a trillion distant comets.
当太阳系穿过一片星云时 When our solar system passes through an interstellar cloud,
大质量星云所产生的引力 the gravity of the massive cloud
会激发最外层的彗星 stirs up the outermost comets.
有些彗星会被抛出太阳系 Some comets will be hurled out
飞向恒星际空间 into the space between the stars.
另外一些则被推到太阳系内部 Others will plunge inward...
朝着太阳而来 falling towards the Sun.
其中的一些会和太阳的行星相撞 And some of them may collide with the planets.
岩态行星和彗星的高速碰撞 The high-speed impact of a comet with a rocky planet
会将许多岩石像火箭般射入太空 will launch boulders like rockets into space.
如果这颗行星上恰巧有生命存在的话 If that planet should happen to be inhabited,
很多岩石会携带乘客 many of those rocks will carry passengers--
有生命力的细菌 living microbes.
数千年后 After thousands of years,
从地球上抛出的岩石碎片 fragments of the rocks ejected from Earth
会以流星的形态进入那些在星云中 can fall as meteors into the atmospheres of newborn planets
新生行星的大气层 in the interstellar cloud.
如果流星中携带的细菌 If the stowaway microbes
能有幸接触到液态水的话 should happen to come in contact with liquid water,
它们就可以复苏并继续繁殖 they can revive and reproduce.
在毫无生机的行星里 This may be how life comes barreling
生命可能就是出现的 into the barren places.
从星云中诞生的恒星 The sun emerges from the cloud,
把生命的种子 having scattered the seeds of life
传播到其他新生恒星中 among the newborn worlds of other stars.
然后这些被赋予了生命的行星 Those new worlds, now touched by life,
将会离开孕育它们的母星云 will then leave their birth cloud
踏上自己的道路 and go their separate ways.
最终 它们将在自己的恒星引领下 Eventually, their stars will carry them
穿越其他星云 through other interstellar clouds,
在那里它们可以继续传播种子 where they may seed still more new worlds.
想象一下这个过程在不同世界中反复发生 Imagine this process repeated from world to world,
每个世界都把生命带到其他地方 each one bringing life to others.
生命不断传播 Life would then propagate,
如同一个缓慢的连锁反应 like a slow chain reaction,
蔓延到整个宇宙 through the entire galaxy.
地球上的生命可能就是这么产生的 This could be how life came to Earth.
但我们也不太确定 We do not know for sure.
宇宙中有我们的同类吗 Are there any beings out there like us?
他们也在问这个问题吗 Do they ask the same questions?
他们和我们一样担忧吗 Do they share our fears?
他们那里也有英雄和冒险故事吗 Do they have heroes and adventures?
如果他们存在的话 那他们在哪 If they do exist, where are they?
他们如何告知外界自己的存在 How might they make their presence known?
我们自己当初又是如何做到这一点的 How did we first announce our presence to the Galaxy?
1946年 It was 1946,
二战结束后的第一年 the year after the Second World War ended.
美军实现和月球的雷达通讯
纵是所拥有超凡想象力的 The vivid imaginations
赫伯特·乔治·威尔斯和巴克·罗杰斯 of HG Wells and Buck Rogers
也未曾想出 never cooked up a more
比新泽西州贝尔玛尔实验室的美军工程师 fantastic experience than the Army engineers at their laboratory
更为奇妙的构想 in Belmar, New Jersey.
这为空间实验 It opens up unlimited possibilities
创造了无限的可能 for interstellar experiment.
美国工程师们 American engineers
向月球发送了一段无线电波 bounced a beam of radio waves off the Moon,
并成功地接收到它的回声 and were able to detect its echo.
他们称这个实验为 戴安娜计划 They called this experiment Project Diana.
这是人类发出的第一条 It was the first interstellar message
星际空间信息 ever sent by our species...
一段诡异的钟声 an eerie, tolling bell.
如果人类的想象力可以摆脱束缚 If one allows the imagination free reign,
未来就会出现无数可能 many future possibilities appear.
载人宇宙飞船 Spaceships, carrying passengers
时速达到几千千米 at thousands of miles per hour,
飞船上的乘客 can be controlled
可以操作飞船 and communication established
并和地球通讯 with their passengers,
因为我们现在已经知道通讯信号 for we now know that the Earth's atmosphere
是可以穿过大气的 can be penetrated.
无线电波以光速传播 Traveling at the speed of light,
只需一秒多的时间 it takes just over one second
就可以到达月球表面 for a radio wave to reach the lunar surface.
但不断扩大的波面远远大于月球 But the expanding wavefront is much bigger than the Moon.
所以多数无线电波都未能抵达月球 Most of the wave passes right by it,
但波的中心部分被月球反射 but the central part gets bounced back.
历经两秒半的往返时间 After a round-trip travel time of two and a half seconds,
无线电波回到地球 it hits our planet.
戴安娜计划通过发送 Project Diana transmitted
一连串每四秒一次的 a series of powerful radio waves--
高强度无线电波 one every four seconds--
来呼叫月球 to "Ping" The Moon.
没有抵达到月球的无线电波将继续传播 The parts that missed the Moon are traveling still.
这不过是序幕而已 It was just the beginning.
二战以后 After World War II,
电视台突然遍布全美 television stations cropped up all over the United States,
以及世界各地 and other parts of the world.
二十世纪以来的 The Project Diana message
戴安娜计划的无线电波 and the FM radio, television and
调频广播 电视和雷达信号 radar signals of the 20th century
都是以光速来传播 all move outward at the speed of light.
传播产生了的巨大的球形无线电波 These transmissions make up a vast sphere of radio waves,
以地球为中心向四面八方扩张 expanding away from the Earth in all directions.
可以说我们的地球是在 You could say that our world
传播它的故事 is radiating stories.
我们的祖先把吉尔伽美什的故事 Our ancestors etched the story of Gilgamesh
刻入泥板 into clay tablets,
让那史诗般的故事流传到未来 sending that epic tale into the future.
我们则把我们的故事用无线电编码 We've encoded our stories in radio waves
然后发射到太空中 and beamed them into space.
自从无线电被发射出去起 They cover one light-year of distance--
每年它们都传播到一光年的距离 that's six trillion miles--
相当于9.5万亿千米 for every year of time since they were sent.
人类发射无线电信号到太空中去 We've been sending our stories into space
已经七十多年头了 for over 70 years.
最早发出的无线电信号 The leading edge of these signals
早已掠过数千颗其他恒星的行星 has already washed over thousands of planets of other stars.
如果这些星球存在着 If any of these worlds are home
拥有射电望远镜的文明 to a civilization with radio telescopes,
他们可能已经知道人类在地球了 they could already know that we're here.
如果其他星球也在把自己的故事 What if other worlds are sending
发送到太空中 那会怎样 their stories into space?
自1960年以来 我们一直在监听 Since 1960, we've been listening
来自地球外的无线电信号 for extraterrestrial radio signals
却并未听到类似钟声的声音 without hearing so much as a tolling bell.
但是我们的研究还太零散 But our search has been sporadic
只拘泥于宇宙中的特定部分 and limited to certain parts of the sky.
如我们所知 For all we know,
我们也许刚刚错过了外星人的信号 we may have just missed an alien signal,
因为在错误的时间 looking in the wrong place
找错了地方 at the wrong time.
我们只监听了的银河系中 We've only listened to a miniscule fraction
一小部分恒星 of the stars in our galaxy.
也许还有其他问题 And there may be another problem...
从某种程度上来说 we are, to some extent,
我们人类是时间的囚徒 prisoners of our own moment in time
并且受到科学技术的限制 and the limits of our technology.
无线电与电视广播 Radio and television broadcasting
在人类的技术发展历程中 may be only a brief passing phase
也许只是昙花一现 in our technological development.
当我们在想象外星文明 When we imagine alien civilizations
通过射电望远镜发射无线电信号时 broadcasting signals with radio telescopes,
我们又与那些幻想着 are we any different from earlier generations
坐炮弹飞到月球的先人们有何区别呢 who imagined riding cannon shells to the Moon?
比人类更先进点的外星文明 Civilizations even slightly more advanced than ours
也许已经改用 may have already moved on
另一种通讯方式了 to some other mode of communication,
一种我们还未发现 one that we have yet to discover
更无法想象的方式了 or even imagine.
他们的信息也许 Their messages could be
此时此刻就围绕在我们周围 swirling around us, at this very moment,
但是我们没有方法来获取这些信息 but we lack the means to perceive them,
就像我们的祖先 just as all of our ancestors,
在一个多世纪前一样 up to a little more than a century ago,
也会无视从其他地方传来的 would have been oblivious to the most urgent radio signal
紧急无线电信号 from another world.
还有一个更棘手的可能性 But there's another, more troubling possibility--
外星文明 就像生物一样 civilizations, like other living things,
都会由于自然原因或暴力 may only live so long before perishing
或是自己造成的破坏 due to natural causes, or violence,
在存在一段时间后消亡 or self-inflicted wounds.
我们是否能够接触到 Whether or not we ever make contact
外星智慧生命 with intelligent alien life
也许取决于另一个重要的问题 may depend on a critical question.
一个文明的寿命是多久 What is the life expectancy of a civilization?
在恩黑杜安娜时代 By the time of Enheduanna,
她第一次在作品上留下了作者名字 the first person to ever get a writing credit,
文明已经出现1000多年了 civilization was already more than 1,000 years old.
但如今 她的繁华之城已是不毛之地 But today, her glorious city is a barren wasteland.
是什么原因 What went wrong?
其中一个原因是美索不达米亚平原上 One problem was the almost ceaseless warfare
城邦之间的近乎无休止的战乱 between the cities of Mesopotamia,
屡次摧毁他们的文明成就 which continually destroyed their achievements.
人们颂扬的伟大军功 They glorified military conquest
最终成为了自身的牺牲品 and ultimately became its victims.
另一个原因是 Another cause of decline
他们的技术知识 was that their technical know-how
已远超他们对于自然的理解 overran their understanding of nature.
设计精巧的灌溉系统 The ingenious irrigation system
这是伟大的美索不达米亚文明的基石 that was the basis for the great civilizations of Mesopotamia
但却造成了意想不到的后果 had an unintended consequence--
每年水都会经灌溉系统流入农田 the water channeled into their farmlands every year
水蒸发后盐分结晶 evaporated and left its salt behind.
经过一代又一代人的灌溉 Over generations, the salt accumulated
盐分的累积让庄稼枯死 and began to kill the crops.
大约在公元前2200年 And then, about 2,200 BC,
就在恩西杜拉娜时代之后不久 not long after the time of Enheduanna,
灾难降临 disaster struck...
极其严重的干旱 a drought of truly epic proportions,
持续了好几十年 lasting for many decades.
焦金流石 草木萧疏 The rains stopped, crops withered,
饿殍遍野 满目疮痍 and there was famine and anarchy.
后来蛮夷入侵 Barbarians invaded.
许多城邦的街道上到处都是死尸 The streets of many cities were littered with dead.
只有一种解释 There could be only one explanation.
至高无上的神 恩利尔 发怒了 Enlil, the supreme god, was angry
因为他的一座寺庙被毁了 because one of his temples had been destroyed.
美索不达米亚人也许不知道 The people of Mesopotamia could not know
同样的干旱吹灭了 that the same drought was crushing
埃及文明的曙光 the dawning civilizations of Egypt,
还有希腊 印度 Greece, India,
巴基斯坦和中国 Pakistan and China.
地球上所有的神 All the gods of the Earth
一定是因为什么事而发怒了 must have been really angry about something.
尽管人们很聪明 For all their brilliance,
但那些文明中的人们 the people of those civilizations had no inkling
并不知道他们在经历气候突变 they were experiencing abrupt climate change.
3000年后 气候也同样 3,000 years later, the climate
给另一个灿烂文明带来了突变 would change abruptly for another glorious civilization,
这次在中美洲 this one in Central America.
在它最巅峰的时候 At its peak,
玛雅文明消亡了 the Mayan civilization perished,
被持续了一世纪的一系列严重干旱 wiped out by a series of severe droughts
所毁灭 over the course of a century.
但这些文明与我们同在 We still carry within us
在我们语言和神话里的 the echoes of these extinct civilizations
那些灭绝文明依旧发出回响 in our languages and our myths.
如今 人类进入了全球化文明的时代 Today, we have a single global civilization.
这次能持续多久 How long will it live?
文明灭绝的方式有很多种 There are so many ways for a civilization to die.
让我们从 Let's start with the ones
人类或许束手无策的情况开始 that we probably wouldn't be able to do much about.
1000光年外的超新星爆发了 That supernova is 1,000 light-years away.
如果再近一点 比方说 If it were much closer, say...
距离地球小于30光年 less than 30 light-years from Earth,
爆发产生的宇宙射线 its cosmic radiation would shred
会打碎地球的大气臭氧保护层 the atmosphere's protective ozone layer
摧毁我们的文明 and destroy our civilization.
幸运的是 起码在未来的几亿年里 Lucky for us, none of the stars close enough to harm us
距离近到能对地球造成伤害的恒星中 are likely to go supernova any time
没有一颗会超新星爆炸 in the next few hundred million years.
每隔一百万年左右 Every million years or so,
地球上会有超级火山爆发 a supervolcano erupts somewhere on Earth.
最近一次发生在七万四千年前的 The last time it happened was 74,000 years ago,
苏门答腊岛上 on the island of Sumatra,
也就是今天的印尼 in what is now Indonesia.
它喷出的 It spewed hundreds of times more
岩石 火山灰和毒气 rock, ash and toxic gas
比有记载以来的任一火山爆发都超出百倍 than any single volcano in recorded history.
熔岩从地壳中喷发出来 The molten rock that erupted from Earth's crust
从火山口 left this caldera,
蔓延100千米 100 kilometers long,
现在这里成了一片湖 now filled with a lake.
多巴火山把超过2500立方千米的碎石 The Toba volcano sent more than 600 cubic miles
喷向了空中 of pulverized rock soaring skyward.
西风把火山灰带去了印度 The westward wind carried the volcanic ash over India,
火山灰就像一块厚毯子一样 where it fell out in a smothering blanket
包裹着整个印度次大陆 over the subcontinent.
这次喷发使上层大气 The eruption loaded the upper atmosphere
充满了硫 with sulfur gases.
火山喷发形成的全球性雾霾 The result was a global haze
阻挡了大部分阳光照射到地面 that blocked most of the sunlight from reaching the surface
这持续了至少五年 for at least five years.
就像一个持续五年之久的阴天一样 It was like one five-year-long cloudy day.
这就是所谓的“火山冬天” This so-called "Volcanic Winter"
类似“核冬天”一样 但是没有核辐射 resembled a "Nuclear winter," But without the radiation.
全球降温 Temperatures fell everywhere.
生活在热带的动植物都被冻住 Plants and animals froze even in the tropics,
成片成片地死亡 dying in enormous numbers.
但是生命是顽强的 But life is hardy.
只有一小部分的物种灭绝了 Only a few species were driven to extinction.
生活在印度中部的先人 One of our ancestors in central India
早在多巴火山爆发的几年前 sharpened this stone blade
把石头磨成了石刀 in the years before the Toba eruption.
我手上的这一把石刀 And this blade
只是人们在火山灰上层的泥土层中 was one of dozens that were found
发现的好几十把石刀中的一把 in the soil layer above the volcanic fallout.
这说明 制作这些工具的人们 This tells us that some toolmakers,
即使是生活在直接受火山影响的地区 even in the area directly affected by the volcano,
还是成功得以从这场灾难中幸存下来 managed to survive the cataclysm.
但是当时的全球人口 But the global human population
必定暴跌 然后又回升 must have plummeted before rebounding.
如果像这样的火上爆发明天就发生 If an eruption like this were to happen tomorrow,
即使人类能幸存下来 our civilization would be brought to its knees,
我们的文明可能也会毁于一炬 although the human species would survive.
可以想象 几百年后我们的技术 I can imagine that our technology of a few hundred years from now
也许可以在喷发前 would allow us to siphon off the energy
吸取那些危险超级火山的能量 of a threatening supervolcano before it explodes.
我们还可以把那些能量转为他用 We could then use that energy for our own purposes.
每百万年 About once every million years,
就会有一颗小行星撞向地球 a small asteroid collides with the Earth,
造成类似程度的破坏 causing a similar amount of devastation.
根据我们现有的科学技术 With our current science and technology,
我们已经知道如何防止小行星撞击 we already know how to prevent an asteroid impact.
我们可以提前数年预测到它的到来 We would see it coming years in advance
并发射宇宙飞船 and could send a spacecraft there
将小行星偏移到对地球无害的轨道 to deflect it into a harmless orbit.
一千年后 我们的科技 With the technology of a thousand years from now,
也许能够减轻 we might even be able to mitigate
地球附近超新星爆发 the deadly effects of a nearby supernova
对地球大气造成的致命影响 on Earth's atmosphere.
那么当危险 But what happens
悄无声息地来临的时候呢 when the danger to a civilization is invisible?
我们又该怎么办 When no one can see it coming?
从哥伦布开始 Beginning with Columbus,
侵略美洲的欧洲人 the European invaders of the Americas
携带着连他们自己都不知道的秘密武器 had a secret weapon that even they knew nothing about.
那就是他们带来的 They were carrying bacteria and viruses
美洲原住民从未接触过的 for deadly diseases, such as smallpox,
致命细菌与病毒 如天花 that the original Americans had never been exposed to.
欧洲人更愿相信 The Europeans like to believe
是他们的勇气 先进的武器 that it was their valor and superior weapons
还有优越的文化征服了新大陆 and culture that won them the New World.
但真正的征服者是 The real conquistadors were
感染并杀死了在北美 中美 南美 the armies of the pathogens that raced on ahead
近九成印第安人 to infect and kill nine out of ten of all the Indians
传播速度极快的病原体 of North, Central and South America.
新大陆上的这个伟大文明 The great civilizations of the New World
在入侵微生物的攻击下毁于一旦 crumbled under the onslaught of invading microbes.
如果没有这支看不见的军队 Without his invisible army,
科尔特斯和他的随从们 Cortez and those who followed
也许根本没有机会征服新大陆 might never have stood a chance.
那么如果文明自我毁灭 又会怎样 But what about civilizations that self-destruct?
我们的经济体系是建立在 Our economic systems were formed
这个星球上的空气 河流 海洋 土地 when the planet and its air, rivers, oceans, lands,
都似乎取之不尽的前提上的 all seemed infinite.
早在人类出现在地球上之前 They evolved long before we first saw the Earth
它们早就开始进化了 as the tiny organism that it actually is.
所有的经济体系都有一个相同点 They're all alike in one respect...
那就是它们都受利益驱动 they're profit-driven,
也因此 它们只关注短期收益 and therefore, focused on short-term gain.
当今现行的经济体系 The prevailing economic systems,
不管它们的意识形态如何 no matter what their ideologies,
都没有内置的机制 have no built-in mechanisms
来保障哪怕100年后的 for protecting our descendants
我们的子孙 of even 100 years from now,
更不用说一万年后了 let alone, 100,000.
从某方面说 我们做得 In one respect, we're ahead of
比古美索不达米亚人更激进 the people of Ancient Mesopotamia.
不同的是 我们知道自己在做什么 Unlike them, we understand what's happening to our world.
例如 我们以过去100万年以来 For example, we're pumping greenhouse gasses
从未有的速度 into our atmosphere at a rate not seen on Earth
排放温室气体 for a million years.
科学界的共识是 And the scientific consensus
人类在使气候变得不稳定 that we're destabilizing our climate.
然而我们的文明似乎对此矢口否认 Yet our civilization seems to be in the grip of denial;
陷入麻木不仁的境地 a kind of paralysis.
人类的所知与所为 There's a disconnect between what we know
总是南辕北辙 and what we do.
能够让我们的行为适应挑战 Being able to adapt our behavior to challenges
是人类智慧的体现 is as good a definition of intelligence as any I know.
如果伟大的智慧是人类这一物种的标志 If our greater intelligence is the hallmark of our species,
我们就应该好好利用 then we should use it,
因为其他的物种都在用它们的独特优势 as all other beings use their distinctive advantages--
来保证自己的子嗣昌盛 to help ensure that their offspring prosper,
让生命得以延续 and their heredity is passed on,
让维系着我们的自然体系受到保护 and that the fabric of nature that sustains us is protected.
当然 人类的智慧是新兴的 Human intelligence is imperfect, surely,
并不完美 and newly arisen.
智慧很容易被甜言所惑 或随波逐流 The ease with which it can be sweet-talked, overwhelmed,
屈服于其他天生的倾向 or subverted by other hard-wired tendencies,
这些倾向有时会扮作一丝理性 sometimes themselves disguised as the light of reason,
其实只是不安 is worrisome.
但如果智慧是我们独特的优势 But if our intelligence is the only edge,
我们就得懂得善用它 we must learn to use it better.
改进它 To sharpen it.
对其局限与不足有自知之明 To understand its limitations and deficiencies.
像猫科动物一样会小心潜伏再骤然出击 To use it as cats use stealth before pouncing.
像竹节虫会披上伪装 As walking sticks use camouflage.
让它成为人类生存的工具 To make it the tool of our survival.
如果我们人类能这样做 If we do this,
接下来的十万年内我们可能面对的所有问题 we can solve almost any problem we are likely to confront
都将迎刃而解 in the next 100,000 years.
现在 我们来到了 And now we've arrived at the place
先人梦想的不朽之地 where our ancient dreams of immortality
和现代天文学的交汇点 and modern astrophysics converge.
巨椭圆星系 Giant elliptical galaxies
就像佛罗里达州 are something like... Florida,
在那里能找到宇宙中最古老的恒星 where the oldest stars in the universe may be found.
这是颗红矮星 This is a red dwarf star,
比太阳更小更昏暗 smaller and fainter than our Sun.
红矮星是宇宙中数量最多的恒星 Red dwarfs are by far the most plentiful stars in the cosmos.
与太阳不同 寿命只有一百亿年 Unlike the Sun, which is halfway through
现在已过了一半 its 10-billion-year lifetime,
红矮星可以为它的行星们 red dwarfs will continue to provide light and warmth
提供光和热超过上万亿年 to their planets for trillions of years.
这比现在宇宙的年龄 That's hundreds of times longer
还要长出百倍 than the present age of the universe.
如果智慧生命可以永生 What would intelligent beings do
他们会做什么 if they had an eternity
来拓展对宇宙的认识 to develop their understanding of the universe?
也许他们能知道如何在宇宙中 Perhaps they would learn how to open shortcuts
开启时空隧道 in the fabric of spacetime,
从而能以比光更快的速度 to travel between galaxies
徜徉于星系之间 faster than the speed of light.
也许他们能创造出全新的宇宙 Maybe they would create whole new universes
就像是艺术或科学的实验 as artistic or scientific experiments.
诚然 没有人 至少地球上没有人 Of course no one, or at least nobody on Earth,
知道永生的人会做些什么 knows what the immortals might do.
如果人类的想象力可以摆脱束缚 If one allows the imagination free reign.
可我们呢 But what about us?
我们的未来是什么样子 What is our own future?
在接下来的140亿年里 What would the Cosmic Calendar
宇宙年历会是什么样子 of the next 14 billion years look like?
如果最初的宇宙年历 If the original Cosmic Calendar
包含了宇宙诞生到现在这一刻的 includes all of time from the birth of the universe
所有时间 until this very moment...
那么在下一个140亿年里 what would the Cosmic Calendar look like
宇宙年历会是什么样子 for the next 14 billion years?
和过去的宇宙年历一样 Just as with the Cosmic Calendar of the past,
未来年历上的每个月 every month the future calendar
相当于10亿年 equals about a billion years;
每一天相当于四千万年 every day, some 40 million.
科学让我们可以预测到 Science makes it possible for us to foretell
在极其遥远的未来 certain astronomical events
发生的某些天文事件 in the unimaginably distant future--
比如 太阳的死亡 the death of the Sun, for example.
在大约50亿年后 In some five billion years,
太阳将会耗尽它的氢 our star will have exhausted its hydrogen--
给它供能的核燃料 the nuclear fuel that powers it--
成为一颗红巨星 becoming a red giant.
这听起来很沮丧 I know that sounds depressing,
但是如果我们能运用我们的智慧 but if we apply our intelligence,
在遥远的未来 我们的后代 our descendants of that distant future
也许早已离开太阳系了 will have long departed from the lost worlds of the Sun.
这都是猜测 Who knows?
人类的活动带来了太多的变量 Human events entail too many variables,
有太多的不确定性 too many uncertainties,
以致很难对人类未来做出科学预测 to make scientific statements about our future.
但我们可以继续梦想 But we can still dream.
人类成就的下一个黄金时代 The next golden age of human achievement
就在此时此刻开启 begins here and now--
下一个宇宙年的新年元旦 New Year's Day of the next cosmic year.
在最初的十分之一秒内 In the first tenth of a second,
我们将蓝色家园放在心上 we take the vision of the pale blue dot to heart,
学会彼此共享这个小小的星球 and learn how to share this tiny world with each other.
世界上的最后一台内燃机 The last internal combustion engine
被放在了博物馆里 is placed in a museum,
气候变化的影响消失开始减轻甚至消失 as the effects of climate change reverse and diminish.
新宇宙年的五分之一秒内 A fifth of a second into this future
人们不再会因贫穷而死去 people will stop dying from the effects of poverty.
地球成为了一个完全自给自足 The planet is now a completely self-sustaining,
互相联系在一起的大组织 intercommunicating organism.
半秒过后 A half-second from now,
极地的冰帽 the polar ice caps are restored
恢复到19世纪的水平 to the way they were in the 19th century,
在下一个宇宙年的一分半钟 and the forecast is mild and pleasant
气候会更加温和宜人 for the next cosmic minute and a half--
也就是四万年 40,000 years.
到了那时 人类已开始 By the time we are ready to settle
向最近的宜居行星系统殖民 even the nearest other planetary systems,
人类已经变了 we will have changed.
经过短短若干代人的时间 The simple passage of so many generations
已改变了人类 will have changed us.
环境强迫我们改变 Necessity will have changed us.
我们是自适应的物种 We are an adaptable species.
不会是人类乘坐者星际方舟 It will not be we who reach Alpha Centauri
抵达南门二 and the other nearby star systems
或是其他附近的恒星系统 on our interstellar arks.
那应该是一个很像人类的物种 It will be a species very like us,
但比我们更强 更少缺点 but with more of our strengths and fewer of our weaknesses;
自信从如 高瞻远瞩 more confident, far-seeing,
更有能力与智慧 capable and wise.
尽管人类有种种弱点 For all our failings,
缺陷与局限 despite our flaws and limitations,
但我们人类仍可称得上伟大 we humans are capable of greatness.
在我们的时代无法实现的梦想和奇迹 What new wonders, undreamt of in our time,
或许会在下一代 will we have accomplished in another generation...
或者是下下代实现 and another?
我们人类这一漂泊的种族 How far will our nomadic species
在下个世纪末或是下个千禧年 have wandered by the end of the next century,
已漫游到了多远 and the next millennium?
我们遥远的后代 Our remote descendants,
安全地到达了 safely arrayed on many worlds
太阳系或是更远的行星系统 throughout the solar system and beyond,
他们将团结在共同的传统之下 will be unified by their common heritage,
团结在对地球家园的敬重下 by their regard for their home planet,
团结在宇宙中或许有其他生命 and by their knowledge that, whatever other life may be,
但人类都是来自地球 the only humans in all the universe
这一共识下 came from Earth.
人们会仰望天空 竭力寻找 They will gaze up and strain to find
天空中的蓝点 the blue dot in their skies.
人们会惊叹 They will marvel at how vulnerable
我们曾经的未来竟是如此脆弱 the repository of all our potential once was,
我们的早年是如此的险恶 how perilous our infancy,
我们的起源是如此的卑微 how humble our beginnings,
我们跨过了多少障碍 how many rivers we had to cross...
才找到了我们的路 找到我们自己 before we found our way.