宇宙诞生于138亿年前 The universe is 13.8 thousand million years old.
为了更好地想像宇宙的历史 In order to imagine all of cosmic time,
我们把它压缩成12个月的年历 let's compress it into a single calendar year.
年历上的1月1号是宇宙诞生的日子 The cosmic calendar begins on January 1st with the birth of our universe.
年历上包含了从那以后经历的所有时间 It contains everything that's happened since then,
一直到现在 up to now,
在这个年历上的12月31号午夜 which on this calendar is midnight December 31st.
按照这个比例 每个月代表10亿年 On this scale, every month represents about a billion years.
每天代表将就4千万年 Every day represents nearly 40 million years.
让我们尽可能地回到过去 Let's go back as far as we can,
回到宇宙最开始的时刻 to the very first moment of the universe.
1月1号 宇宙大爆炸 January 1st, the Big Bang.
目前而言这是我们所能看到最早的时间 It's as far back as we can see in time... for now.
整个宇宙形成于一个比原子还小的点 Our entire universe emerged from a point smaller than a single atom.
空间在密度极大温度极高的状态下爆炸 Space itself exploded in a cosmic fire,
由此开始了宇宙的扩张 launching the expansion of the universe
并诞生了所有的能量 and giving birth to all the energy
还有已经产生的那些所有我们已知的事物 and all the matter we know today.
听上去很疯狂 I know that sounds crazy,
但是我们有很强力的观测证据 but there's strong observational evidence
来支持宇宙大爆炸理论 to support the Big Bang theory.
证据还有氦元素在宇宙中的比例 And it includes the amount of helium in the cosmos
以及爆炸残留的发光无线电频谱 and the glow of radio waves left over from the explosion.
爆炸后宇宙开始冷却 As it expanded, the universe cooled,
其间有2亿年左右的黑暗 and there was darkness for about 200 million years.
万有引力将气体集聚并且加热 Gravity was pulling together clumps of gas and heating them
直到第一批恒星发出亮光 until the first stars burst into light
相当于1月10号 on January 10th.
1月13号 这些恒星开始结合 On January 13th, these stars coalesced
形成第一批小星系 into the first small galaxies.
这些星系融合成更大的星系 These galaxies merged to form still larger ones,
包括我们的银河系 including our own Milky Way,
产生于110亿年左右 which formed about 11 billion years ago,
就是宇宙年历上的3月15号 on March 15th of the cosmic year.
数千亿的恒星中 Hundreds of billions of suns.
哪个是我们的太阳 Which one is ours?
此时尚未诞生 It's not yet born.
它将从其他恒星的灰烬中产生 It will rise from the ashes of other stars.
看到这些犹如闪光灯般的亮光吗 See those lights flashing like paparazzi?
它们都是超新星 Each one is a supernova,
一颗超大恒星的耀眼爆炸 the blazing death of a giant star.
恒星消亡和诞生的地方 Stars die and are born in places like this one...
我们称为星星苗圃 a stellar nursery.
又称分子云
他们像雨滴般 They condense like raindrops
从巨大的气态和灰尘云中凝结 from giant clouds of gas and dust.
他们温度高的可以把原子中的原子核 They get so hot that the nuclei of the atoms
融合在一起 fuse together deep within them
从而产生了我们呼吸的氧气 肌肉中的碳元素 to make the oxygen we breathe, the carbon in our muscles,
骨头中的钙元素 血中的铁元素 the calcium in our bones, the iron in our blood,
所有的这一切都产生于 all of it was cooked
从此消亡的恒星炙热的内心 in the fiery hearts of long-vanished stars.
你 我 所有人 You, me, everyone...
我们都是由星辰物质组成 we are made of star stuff.
星辰物质被不断循环和浓缩 This star stuff is recycled and enriched,
一遍又一遍 again and again,
经过几代恒星的诞生消亡 through succeeding generations of stars.
离我们的太阳诞生还有多久 How much longer until the birth of our Sun?
很长时间 A long time.
我们太阳的第一次发光 It won't begin to shine
还要再等60亿年 for another six billion years.
太阳的生日是8月31号 Our Sun's birthday is August 31st
在这个宇宙年历上 on the Cosmic Calendar...
45亿年前 ...four and a half billion years ago.
就像太阳系中其他行星 As with the other worlds of our solar system,
地球在一堆气体和灰尘中产生 Earth was formed from a disk of gas and dust
绕着新生的太阳运行 orbiting the newborn Sun.
反覆的碰撞产生了一个发光的球状碎片 Repeated collisions produced a growing ball of debris.
看到那个小行星了吗 See that asteroid?
不是那个 No, not that one.
那边的那个 The one over there.
我们的存在归功于它旁边的引力 We exist because the gravity of that one next to it
把它轻轻向左推了一英吋 just nudged it an inch to the left.
一英吋有很大的区别吗 What difference could an inch make
按照太阳系的比例来说 on the scale the solar system?
稍等 你马上就能看到 Just wait, you'll see.
在最初的10亿年里 The Earth took one hell of a beating
地球饱受摧残 in its first billion years.
任由轨道上的碎片撞击和融合 Fragments of orbiting debris collided and coalesced,
直到他们形成了我们的月亮 until they snowballed to form our Moon.
月亮是那个暴力纪元的纪念品 The Moon is a souvenir of that violent epoch.
如果你站在远古地球的表面 If you stood on the surface of that long ago Earth,
月亮会看上去比现在亮100倍 the Moon would have looked a hundred times brighter.
那时月亮离我们近10倍 It was ten times closer back then,
被比现在更强大的引力场吸引着 locked in a much more intimate gravitational embrace.
地球冷却下来 海洋形成了 As the Earth cooled, seas began to form.
海浪比现在高1000倍 The tides were a thousand times higher then.
经过极漫长的时间 潮汐的摩擦力 Over the eons, tidal friction within Earth
将月球推远 pushed the Moon away.
生命差不多在这个时候诞生 Life began somewhere around here,
9月21号 September 21st,
在地球上的35亿年前 three and a half billion years ago on our little world.
我们依然不知道生命如何起源 We still don't know how life got started.
我们只是知道 For all we know,
有可能是来自银河系的其他地方 it may have come from another part of the Milky Way.
生命的起源 The origin of life
是最伟大的未知科学奇迹之一 is one of the greatest unsolved mysteries of science.
生命的演变 That's life cooking,
一切生物化学的进化 evolving all the biochemical recipes
充满了无与伦比的复杂活动 for its incredibly complex activities.
到了11月9号 生命开始呼吸 移动 By November 9th, life was breathing, moving,
进食和对周遭环境作出反应 eating, responding to its environment.
多亏了这些有开拓性的微生物 We owe a lot to those pioneering microbes.
没错 就是这些不起眼的家伙 Oh, yeah... one other thing.
他们还发明了繁殖 They also invented sex.
12月17号 很特别的一天 December 17th was quite a day.
海洋中生命的发展开始腾飞 Life in the sea really took off,
形形色色的大型植物和动物 it was exploding with a diversity
爆炸式地发展 of larger plants and animals.
提塔利克鱼是最早冒险登陆的动物之一 Tiktaalik was one of the first animals to venture onto land.
感觉肯定像是造访另一个星球 It must have felt like visiting another planet.
森林 恐龙 Forests, dinosaurs,
鸟类 昆虫 birds, insects,
都在12月的最后一周进化而来 they all evolved in the final week of December.
第一朵花 The first flower...
在12月28号 盛开 bloomed on December 28th.
随着古森林的成长死亡 As these ancient forests grew and died
并被深埋进地下 and sank beneath the surface,
他们的残骸形成了煤 their remains transformed into coal.
3亿年后 300 million years later,
人类燃烧这些煤来推动文明的发展 we humans are burning most of that coal to power
同时也使我们的文明陷入危机 and imperil our civilization.
还记得那颗在太阳系形成时的 Remember that asteroid back in the formation
小行星吗 of the solar system...
那颗被轻轻推动的小行星 the one that got nudged a little to the left?
它来了 Well, here it comes.
宇宙年历上的12月30号 早晨6点24分 It's 6:24 AM on December 30th on the Cosmic Calendar.
在1亿年的时间里 For more than a hundred million years,
恐龙曾是这个地球的统治者 the dinosaurs were lords of the Earth,
当我们的祖先 小型哺乳动物 while our ancestors, small mammals,
战战兢兢地在地面爬来爬去的时候 scurried fearfully underfoot.
这颗小行星改变了一切 The asteroid changed all that.
假如它没有被推动 Suppose it hadn't been nudged at all.
它会完全和地球擦肩而过 It would have missed the Earth entirely,
恐龙恐怕依然存在 and for all we know, the dinosaurs might still be here
但我们不会 but we wouldn't.
这是极端突发状况的好例子 This is a good example of the extreme contingency,
生存的偶然性 the chance nature, of existence.
宇宙已经诞生超过135亿年 The universe is already more than 13 and a half billion years old.
人类仍未出现 Still no sign of us.
在这个年历代表的时间长河中 In the vast ocean of time that this calendar represents,
人类在宇宙年历中的最后一天 we humans only evolved within the last hour
最后一小时进化而来 of the last day of the cosmic year.
11点59分46秒 11:59 and 46 seconds.
全部有记载的历史发生在最后的14秒里 All of recorded history occupies only the last 14 seconds,
你听说过的所有人 and every person you've ever heard of
存在于这个点的某个位置 lived somewhere in there.
那些国王 战役 迁徙 发明 All those kings and battles, migrations and inventions,
战争和爱情 写在历史书中的一切 wars and loves, everything in the history books
都发生在这宇宙年历中的最后几秒 happened here, in the last seconds of the Cosmic Calendar.
但如果我们想要研究 But if we want to explore
宇宙年历中这段极短的时间 such a brief moment of cosmic time...
我们必须改变比例 ...we'll have to change scale.
我们是这个宇宙的新丁 We are newcomers to the cosmos.
我们的历史仅仅从宇宙年的最后一晚开始 Our own story only begins on the last night of the cosmic year.
现在是新年前夜的9点45分 It's 9:45 on New Year's Eve.
350万年前 Three and a half million years ago,
你我的祖先留下这些足迹 our ancestors, yours and mine, left these traces.
我们站了起来和他们区别开来 We stood up, and parted ways from them.
自从我们直立行走 Once we were standing on two feet,
我们的双眼不在迷恋地面 our eyes were no longer fixated on the ground.
现在我们可以自由的探索奇迹 Now we were free to look up in wonder.
人类存在的大部分时间里 For the longest part of human existence,
比方说最近的4万代人 say the last 40,000 generations,
我们曾是流浪者 we were wanderers,
猎人和采集者混住在一起 living in small bands of hunters and gatherers,
制作工具 生火 making tools, controlling fire,
给事物起名字 naming things,
都发生在宇宙年历的最后一个小时里 all within the last hour of the Cosmic Calendar.
我们必须改变比例去继续探寻 To find out what happens next, we'll have to change scale
最后一晚的最后一分钟 to see the last minute of the last night
发生了什么 of the cosmic year.
11点59分 11:59
以宇宙时间比例来说我们太太太年轻了 We're so very young on the time scale of the universe
我们甚至还没开始画出第一张画 that we didn't start painting our first pictures
直到宇宙年历的最后60秒 until the last 60 seconds of the cosmic year,
只不过是3万年前 a mere 30,000 years ago.
我们发明了天文学 This is when we invented astronomy.
事实上我们都是天文学家的后裔 In fact, we're all descended from astronomers.
我们的生存要依靠研究星星 Our survival depended on knowing how to read the stars
用来预测冬天的到来 in order to predict the coming of the winter
以及兽群的迁徙 and the migration of the wild herds.
然后大约1万年前 And then, around 10,000 years ago,
我们的生活方式迎来了变革 there began a revolution in the way we lived.
我们的祖先学会了如何改变周围环境 Our ancestors learned how to shape their environment,
栽培植物 驯养动物 taming wild plants and animals,
耕作土地 定居下来 cultivating land and settling down.
这改变了一切 This changed everything.
有史以来第一次 For the first time in our history,
我们可以拥有超过我们负重能力的东西 we had more stuff than we could carry.
我们需要把这些数量记录下来 We needed a way to keep track of it.
午夜前的14秒 At 14 seconds to midnight,
大约6千年前 我们发明了书写 or about 6,000 years ago, we invented writing.
随后不久我们就开始记录其他东西 And it wasn't long before we started recording
不仅仅是粮食的数量 more than bushels of grain.
书写让我们保存我们的想法 Writing allowed us to save our thoughts
并且跨越时间和空间的传播它们 and send them much further in space and time.
泥板上的细小印记 Tiny markings on a clay tablet
成了我们征服有限的生命的手段 became a means for us to vanquish mortality.
震撼了整个世界 It shook the world.
摩西出生于7秒之前 Moses was born seven seconds ago.
释迦摩尼 6秒前 Buddha, six seconds ago.
耶稣基督 5秒前 Jesus, five seconds ago.
穆罕穆德 3秒前 Mohammed, three seconds ago.
不到2秒前 不论好坏 It was not even two seconds ago that, for better or worse,
地球一边的人类发现了地球的另一边 the two halves of the Earth discovered each other.
仅仅在最后的一秒钟里 And it was only in the very last second
我们开始使用科学 of the Cosmic Calendar that we began to use science
去揭示大自然的秘密和规则 to reveal nature's secrets and her laws.
科学方法是如此的强大 The scientific method is so powerful
只用了4个世纪的时间 that in a mere four centuries,
就从伽利略第一次看向望远镜 it has taken us from Galileo's first look through a telescope
到人类在月球上留下足迹 at another world to leaving our footprints on the Moon.
它让我们可以越过时间和空间 It allowed us to look out across space and time
去观察我们在宇宙时空中的位置 to discover where and when we are in the cosmos.
我们有了了解宇宙本质的办法 We are a way for the cosmos to know itself.
卡尔·萨根30多年前带领我们进行了首次的宇宙航行 Carl Sagan guided the maiden voyage of Cosmos a generation ago.
他不仅是20世纪最成功的 He was the most successful science communicator
科学传播者 of the 20th century,
也是一位首屈一指的科学家 but he was first and foremost a scientist.
卡尔为我们了解行星 Carl contributed enormously
作出了极大的贡献 to our knowledge of the planets.
他正确地预测了木星的卫星 泰坦 土卫六上 He correctly predicted the existence of methane lakes
有沼气湖的存在 on Saturn's giant moon Titan.
他指出早期地球的大气层中 He showed that the atmosphere of the early Earth
必然含有强大的温室气体 must have contained powerful greenhouse gases.
他首先推断出火星上的季节变化 He was the first to understand that seasonal changes on Mars
是由沙尘暴引起 were due to windblown dust.
卡尔是一位 Carl was a pioneer
在探索地球以外智慧生物领域的先驱 in the search for extraterrestrial life and intelligence.
太空时代的最初40年里 每次主要的 He played a leading role in every major spacecraft mission
太阳系探索航天任务 他都担任了重要的职务 to explore the solar system during the first 40 years of the Space Age.
但他做的 不仅仅只有这些 But that's not all he did.
这是卡尔的一本1975年的记事日历 This is Carl Sagan's own calendar from 1975.
我那时在做什么 Who was I back then?
12月20日 奈尔·德葛拉司·泰森
我只是一个纽约的17岁男孩 I was just a 17-year-old kid from the Bronx
梦想着可以成为科学家 with dreams of becoming a scientist,
世界上最著名的天文学家 and somehow the world's most famous astronomer found time
邀请我去纽约州 to invite me to Ithaca, in upstate New York,
和他共度一个周六 and spend a Saturday with him.
我记得那天下着雪 I remember that snowy day like it was yesterday.
他来公车站接我 He met me at the bus stop
带我参观了他在康奈尔大学的实验室 and showed me his laboratory at Cornell University.
卡尔从书桌后拿出这本书并在上面为我题字 Carl reached behind his desk and inscribed this book for me.
《宇宙的联系》(The Cosmic Connection)
"致 尼尔 未来的天文学家 "For Neil, a future astronomer.
卡尔" Carl."
结束后 他开车送我去公车站 At the end of the day, he drove me back to the bus station.
雪下得更大了 The snow was falling harder.
他写下他的电话号码 家里的电话 He wrote his phone number... his home phone number...
写在一张小纸片上 然后跟我说 "如果公车没有来 on a scrap of paper and he said, "If the bus can't get through,
打电话给我 就在我家过夜" call me and spend the night at my home with my family."
我当时已经决定要当一名科学家 I already knew I wanted to become a scientist,
但是那天下午 我认识到 but that afternoon, I learned from Carl
我要做他那样的人 the kind of person I wanted to become.
他帮助了我 还有其他很多人 He reached out to me and to countless others,
激励我们去学习 教授 研究科学 inspiring so many of us to study, teach and do science.
科学研究是一份需要合作的事业 Science is a cooperative enterprise,
持续几代人的时间 spanning the generations.
就如同一支火炬在老师与学生的手中传递 It's the passing of a torch from teacher to student to teacher,
一群伟大的思想从远古贯穿 a community of minds reaching back to antiquity
直至未来的星空 and forward to the stars.
现在跟我来 Now, come with me.
我们的旅程才刚刚开始 Our journey is just beginning.