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  • Translator: Ivana Korom Reviewer: Krystian Aparta

    譯者: Lilian Chiu 審譯者: Helen Chang

  • We are all atomically connected.

    在原子上,我們都是相連的。

  • Fundamentally, universally.

    根本上,宇宙上,都是。

  • But what does that mean?

    但,那是什麼意思?

  • I'm an astrophysicist, and as such,

    我是天體物理學家,因此,

  • it is my responsibility to trace the cosmic history

    我的責任是要追蹤你的每一個原子

  • of every single one of your atoms.

    背後的宇宙歷史。

  • In fact, I would say

    事實上,我會說,

  • that one of the greatest achievements of modern astronomy

    現代天文學最偉大的成就之一,

  • is the understanding of how our atoms were actually put together.

    就是了解我們的原子 是如何形成的。

  • While hydrogen and helium were made

    在大爆炸的前兩分鐘,

  • during the first two minutes of the big bang,

    氫和氦就形成了,

  • the origin of heavy elements,

    但,重元素如血液中的鐵、

  • such as the iron in your blood, the oxygen we're breathing,

    我們所呼吸的氧氣、

  • the silicone in your computers,

    電腦中用的矽,

  • lies in the life cycle of stars.

    則起源於星星的生命循環。

  • Nuclear reactions take lighter elements and transform them into heavier ones,

    核反應會把較輕的元素

  • and that causes stars to shine

    轉換成較重的元素,

  • and ultimately explode,

    那會導致星星的發光,

  • therefore enriching the universe with these heavy elements.

    最終發生爆炸,

  • So without stellar death

    因而讓宇宙中充滿了這些重元素。

  • there would be no oxygen

    若沒有星星的死亡,

  • or other elements heavier than hydrogen and helium,

    就不會有氧,

  • and therefore, there would be no life.

    或者其他比氫和氦更重的元素,

  • There are more atoms in our bodies

    因此,就不會有生命。

  • than stars in the universe.

    在我們身體中的原子數

  • And these atoms are extremely durable.

    比宇宙中的星星還多。

  • The origins of our atoms

    這些原子非常耐久。

  • can be traceable to stars that manufactured them in their interiors

    我們原子的源頭

  • and exploded them all across the Milky Way,

    可追溯至星星在內部製造它們,

  • billions of years ago.

    接著將它們炸出來,穿過銀河,

  • And I should know this,

    這是數十億年前的事。

  • because I am indeed a certified stellar mortician.

    我會知道這些,

  • (Laughter)

    是因為我是有認證的 星星殯葬業者。

  • And today, I want to take you on a journey that starts in a supernova explosion

    (笑聲)

  • and ends with the air that we're breathing right now.

    今天我想要帶大家踏上一段旅程,

  • So what is our body made of?

    從超級新星的爆炸開始,

  • Ninety-six percent consists of only four elements:

    一直到我們現在呼吸的空氣為止。

  • hydrogen, carbon, oxygen and nitrogen.

    我們的身體是什麼組成的?

  • Now the main character of this cosmic tale is oxygen.

    其中 96% 只由四個元素組成:

  • Not only is the vast majority of our bodies made of oxygen,

    氫、碳、氧、氮。

  • but oxygen is the one element fighting to protect life on earth.

    這個宇宙故事的主角是氧。

  • The vast majority of oxygen in the universe

    不僅我們的身體很大一部分 都是由氧所構成,

  • was indeed produced over the entire history of the universe

    在地球上,氧也是 在努力保護生命的元素。

  • in these supernova explosions.

    宇宙中大部分的氧

  • These supernova explosions signal the demise of very massive stars.

    的確是在整個宇宙歷史中

  • And for a brilliant month,

    從這些超級新星的爆炸製造出來。

  • one supernova explosion can be brighter than an entire galaxy

    這些超級新星的爆炸, 表示有非常巨大的星星死亡了。

  • containing billions of stars.

    在這明亮的一整個月中,

  • That is truly remarkable.

    一個超級新星爆炸的亮度就超過了

  • That is because massive stars burn brighter

    包含數十億顆星星的銀河。

  • and have a spectacular death, compared to other stars.

    這真的很驚人。

  • Nuclear fusion is really the lifeblood of all stars,

    這是因為巨大的星星 燃燒起來會更明亮,

  • including the sun,

    且和其他星星相比, 它的死亡也更壯麗。

  • and as a result is the root source of all the energy on earth.

    核融合是所有星星的命脈,

  • You can think of stars as these fusion factories

    包括太陽,

  • which are powered by smashing atoms together

    因此也是地球上所有能量的根源。

  • in their hot and dense interiors.

    可以把這些星星想成是融合工廠,

  • Now, stars like our sun,

    工廠的動力來源則是 在其又熱又密的內部

  • which are relatively small,

    將原子彼此撞擊。

  • burn hydrogen into helium,

    星星就像我們的太陽,

  • but heavier stars of about eight times the mass of the sun

    它們相對很小,

  • continue this burning cycle

    將氫燃燒成為氦,

  • even after they exhausted their helium in their cores.

    但,比較重的星星 質量有太陽的八倍,

  • So at this point,

    它們會持續這個燃燒循環,

  • the massive star is left with a carbon core,

    即使在它們核心的氦 已經耗盡,仍會持續。

  • which, as you know, is the building block of life.

    此時,

  • This carbon core continues to collapse

    巨大的星星剩下一個碳核心,

  • and as a result, the temperature increases,

    也就是建造生命的積木。

  • which allows further nuclear reactions to take place,

    這個碳核心會持續崩塌,

  • and carbon then burns into oxygen,

    因此,溫度會上升,

  • into neon, silicon, sulphur

    讓進一步的核融核發生,

  • and ultimately iron.

    接著,碳會燃燒成為氧,

  • And iron is the end.

    成為氖、矽、硫,

  • Why?

    最終成為鐵。

  • Because iron is the most bound nuclei in the universe,

    鐵就是終點。

  • which means that we cannot extract energy by burning iron.

    為什麼?因為鐵是 宇宙中最被束縛的核心,

  • So when the entire core of the massive star is made of iron,

    意即,我們無法透過 燃燒鐵來取得能量。

  • it's run out of fuel.

    當巨大星星的整個核心

  • And that's an incredibly bad day for a star.

    都變成鐵做的,它就沒有燃料了。

  • (Laughter)

    對星星而言,那是很糟糕的一天。

  • Without fuel, it cannot generate heat,

    (笑聲)

  • and therefore gravity has won the battle.

    沒有燃料,它就無法產生熱,

  • The iron core has no other choice but to collapse,

    因此,引力就打贏了這場仗。

  • reaching incredibly high densities.

    鐵核心沒有其他選擇,只能崩塌,

  • Think of 300 million tons

    達到非常高的密度。

  • reduced to a space the size of a sugar cube.

    想想看,三億公噸的重量,

  • At these extreme high densities, the core actually resists collapse,

    縮小到一塊方糖的大小。

  • and as a result,

    在這個極高的密度之下, 核心會抵抗崩塌,

  • all of this infalling material bounces off the core.

    因此,

  • And this dramatic bounce,

    所有這些下塌的物質 會被核心反彈。

  • which happens in a fraction of a second or so,

    這戲劇性的反彈時間不到一秒鐘,

  • is responsible for ejecting the rest of the star in all directions,

    但就造成星星的其他部分 朝向各個方向射出,

  • ultimately forming a supernova explosion.

    最終,形成了超級新星爆炸。

  • So, sadly, from the perspective of an astrophysicist,

    所以,感傷的是,

  • the conditions in the centers of these exploding stars

    從天體物理學家的角度來看,

  • cannot be recreated in a laboratory.

    我們無法在實驗室中重新創造出

  • (Laughter)

    這些爆炸星星中心的條件。

  • Now, thankfully for humanity, we're not able to do that.

    (笑聲)

  • (Laughter)

    人類應該覺得謝天謝地 我們做不到這件事。

  • But what does that mean?

    (笑聲)

  • That means that as astrophysicists,

    但那就意味著天體物理學家

  • we have to rely on sophisticated computer simulations

    必須要仰賴精密的電腦模擬

  • in order to understand these complex phenomena.

    來了解這些複雜的現象。

  • These simulations can be used to really understand how gas behaves

    這些模擬可以用來真正了解

  • under such extreme conditions.

    氣體在這些極端條件下的行為。

  • And can be used to answer fundamental questions

    也可以用來回答基礎的問題,

  • like, "What ultimately disrupted the massive star?"

    如,「最終,巨大的星星 是被什麼瓦解的?」

  • "How is it that this implosion can be reversed into an explosion?"

    「這種向內爆炸怎麼能夠 被反轉成向外爆炸?」

  • There's a huge amount of debate in the field,

    在這個領域中有很多辯論,

  • but we all agree that neutrinos,

    但大家都認同微中子,

  • which are these elusive elementary particles,

    也就是這些很難捉摸的基本粒子,

  • play a crucial role.

    扮演著關鍵的角色。

  • Yeah?

    是吧?

  • I'm about to show you one of those simulations.

    我等下會讓各位看其中一項模擬。

  • So neutrinos are produced in huge numbers once the core collapses.

    一旦核心崩塌,就會有 大量的微中子產生。

  • And in fact,

    事實上,

  • they are responsible for transferring the energy in this core.

    在核心中能量的傳遞就要靠它們。

  • Like thermal radiation in a heater,

    就像暖氣機中的熱輻射,

  • neutrinos pump energy into the core,

    中子會把能量打入核心中,

  • increasing the possibility of disrupting the star.

    增加瓦解星星的可能性。

  • In fact, for about a fraction of a second,

    事實上,在大約一秒鐘的時間中,

  • neutrinos pump so much energy

    中子會打入非常多能量, 讓壓力增加到

  • that the pressure increases high enough that a shock wave is produced

    足以產生出衝擊波,

  • and the shock wave goes and disrupts the entire star.

    衝擊波便會瓦解整個星星。

  • And it is in that shock wave where elements are produced.

    而元素正是在 那衝擊波當中產生的。

  • So thank you, neutrinos.

    所以,謝謝你,微中子。

  • (Laughter)

    (笑聲)

  • Supernovas shine bright,

    超級新星很明亮,

  • and for a brief period of time,

    在一段很短暫的時間中,

  • they radiate more energy than the sun will in its entire lifetime.

    它們放射出的能量超過 太陽一生所放射出的能量。

  • That point of light that you see there,

    各位看到的這個光點,

  • which was certainly not there before,

    它以前肯定不在那裡,

  • burns like a beacon,

    它燃燒起來亮得像燈塔一樣,

  • clearly indicating the position where the massive star has died.

    清楚指出巨大星星死亡的位置。

  • In a galaxy like our own Milky Way,

    在像我們這樣的銀河中,

  • we estimate that about once every 50 years,

    我們估計,大約每五十年

  • a massive star dies.

    就有一個巨大星星死亡。

  • This implies that somewhere in the universe,

    這就表示,每一秒鐘左右,

  • there's a supernova explosion every second or so.

    在宇宙中的某處 就有一個超級新星爆炸。

  • And thankfully for astronomers,

    對天文學家而言,謝天謝地,

  • some of them are actually found relatively close to earth.

    當中有些還非常靠近地球。

  • Various civilizations recorded these supernova explosions

    在早望遠鏡發明之前,

  • long before the telescope was invented.

    就有許多文明記載了 超級新星爆炸的記錄。

  • The most famous of all of them

    當中最有名的,

  • is probably the supernova explosion that gave rise to the Crab Nebula.

    可能就是形成蟹狀星雲的 那個超級新星爆炸。

  • Yeah?

    對吧?

  • Korean and Chinese astronomers recorded this supernova in 1054,

    1054 年,韓國和中國的天文學家

  • as did, almost certainly, Native Americans.

    就記錄下了這個超級新星,

  • This supernova happened about 5,600 light-years away from earth.

    幾乎可以肯定, 美國原住民也有這項記載。

  • And it was so incredibly bright

    這顆超級新星在距離地球 大約五千六百光年的地方。

  • that astronomers could see it during the day.

    它非常亮,

  • And it was visible to the naked eye for about two years in the night sky.

    天文學家在白天就能看見它。

  • Fast forward 1,000 years or so later, and what do we see?

    有大約兩年的時間, 晚上都可以用肉眼看見它。

  • We see these filaments that were blasted by the explosion,

    快轉一千年左右,我們看到什麼?

  • moving at 300 miles per second.

    我們看到爆炸炸開的這些光絲,

  • These filaments are essential for us to understand

    移動速度為每秒鐘三百英里。

  • how massive stars die.

    若我們要了解巨大星星如何死亡,

  • The image that you see there

    這些光絲就非常重要。

  • was assembled by the Hubble Space Telescope

    各位看見的這張影像 是用哈伯太空望遠鏡

  • over a span of three months.

    收集了三個月時間的成果。

  • And it is incredibly important to astronomers

    它對天文學家非常重要,

  • because it ultimately carries the chemical legacy

    因為,最終,它帶著 爆炸星星的化學遺產。

  • of the star that exploded.

    各位看見的橘色光絲

  • The orange filaments that you see there are the tattered remains of the star,

    是星星的破爛殘駭,

  • and are made primarily of hydrogen,

    主要是由氫所構成,

  • while the blue and red filaments that you see

    至於藍色和紅色的光絲

  • are the freshly synthesized oxygen.

    則是剛合成的氧。

  • So studying supernova remnants, like the Crab Nebula,

    所以,天文學家透過 研究超級新星的殘餘物,

  • allowed astronomers to firmly conclude

    比如蟹狀星雲,就能肯定地下結論

  • that the vast majority of oxygen on earth was produced by supernova explosions

    認為地球上絕大部分的氧氣是由

  • over the history of the universe.

    宇宙歷史上的超級新星 爆炸所產生的。

  • And we can estimate

    我們可以估計,

  • that in order to assemble all the atoms of oxygen in our body,

    要集合出我們身體中 所有的氧原子,

  • it took on the order of a 100 million supernova.

    會需要大約一億個超級新星。

  • So every bit of you, or at least the majority of it,

    所以,各位的全身上下, 至少絕大部分,

  • came from one of these supernova explosions.

    都來自其中一個超級新星爆炸。

  • So now you may be wondering,

    現在,各位可能會納悶,

  • how is it that these atoms

    在這些極端的條件下 產生出來的原子

  • that were generated in such extreme conditions

    最終怎麼會進到我們的身體?

  • ultimately took residence in our body?

    我想請大家來做一個思想實驗。

  • So I want you to follow the thought experiment.

    想像我們銀河出現了一顆超級新星。

  • Imagine that we're in the Milky Way, and a supernova happens.

    它把大量的氧原子炸出來,

  • It blasted tons and tons of oxygen atoms

    進入空蕩蕩的太空中。

  • almost into empty space.

    當中少數組合成了星雲。

  • A few of them were able to be assembled in a cloud.

    四十五億年前,

  • Now, 4.5 billion years ago,

    某樣東西動搖了 那星雲,讓它崩塌,

  • something unsettled that cloud and caused it to collapse,

    在其中心形成了太陽以及太陽系。

  • forming the sun in its center and the solar system.

    所以,太陽、行星, 以及地球上的生命

  • So the sun, the planets and life on earth

    都要仰賴這個美麗的循環:

  • depend on this beautiful cycle

    恆星誕生、恆星死亡、恆星再生。

  • of stellar birth, stellar death and stellar rebirth.

    因此,宇宙中的原子回收 也持續進行下去。

  • And this continues the recycling of atoms in the universe.

    因此,天文學和化學 有著密切的關聯。

  • And as a result, astronomy and chemistry are intimately connected.

    我們這種生命形式,

  • We are life forms that have evolved to inhale the waste products of plants.

    演化成會吸入植物的廢棄產物。

  • But now you know

    但,現在各位知道我們也會 吸入超級新星爆炸的廢棄產物。

  • that we also inhale the waste products of supernova explosions.

    (笑聲)

  • (Laughter)

    所以,花點時間,深深吸口氣。

  • So take a moment, inhale.

    氧原子剛進入了你的身體。

  • An oxygen atom has just gone into your body.

    可以肯定,那氧原子

  • It is certain that that oxygen [atom]

    記得它曾待在一個星星的內部,

  • remembers that it was in the interior of a star

    且它很可能是由 超級新星爆炸所產生的。

  • and it was probably manufactured by a supernova explosion.

    這個原子可能穿過了整個太陽系,

  • This atom may have traveled the entire solar system

    才落在地球上,

  • until it splashed on earth,

    又過了好長的時間才遇到你。

  • long before reaching you.

    當我們呼吸時,

  • When we breathe,

    每天要用掉數百公升的氧。

  • we use hundreds of liters of oxygen every day.

    所以,我非常幸運能夠 站在這群美好的觀眾面前,

  • So I'm incredibly lucky to be standing in front of this beautiful audience,

    但我其實是在偷你們的氧原子。

  • but I'm actually stealing your oxygen atoms.

    (笑聲)

  • (Laughter)

    因為我在對各位說話,

  • And because I'm speaking to you,

    我會把一些曾經在 我體內的氧原子還給你們。

  • I'm giving you some of them back, that once resided in me.

    所以,呼吸吧,

  • So breathing, yeah,

    參與這美好的原子交換。

  • participates in this beautiful exchange of atoms.

    接著,各位可以問:

  • And you can then ask,

    「我們體內有多少原子

  • "Well, how many atoms in our body once belonged to Frida Kahlo?"

    曾經屬於芙烈達卡蘿(畫家)?」

  • (Laughter)

    (笑聲)

  • About 100,000 of them.

    大約十萬個。

  • 100,000 more probably belonged to Marie Curie,

    可能還有十萬個是屬於居禮夫人,

  • 100,000 more to Sally Ride,

    另外十萬個屬於 莎莉萊德(物理學家),

  • or whoever you want to think of.

    或其他你想到的人。

  • So breathing is not only filling our lungs with cosmic history,

    所以,呼吸讓我們的肺部

  • but with human history.

    不僅充滿宇宙的歷史,

  • I would like to end my talk by sharing a myth

    也充滿人類的歷史。

  • that is very close to my heart.

    我想分享一個和我關係密切神話, 作為這場演說的結尾。

  • A myth from the Chichimeca culture,

    這個神話來自奇奇梅克文化,

  • which is a very powerful Mesoamerican culture.

    它是個非常強大的中美洲文化。

  • And the Chichimecas believe

    奇奇梅克相信,

  • that our essence was assembled in the heavens.

    我們的本質是在天上合成的。

  • And on its journey towards us,

    在來到我們這裡的路上,

  • it actually fragmented into tons of different pieces.

    破成了非常多不同的碎片。

  • So my abuelo used to say,

    我祖父以前常說:

  • "One of the reasons you feel incomplete

    「你會感到不完整,理由之一

  • is because you are missing your pieces."

    是因為你少了你的碎片。」

  • (Laughter)

    (笑聲)

  • "But don't be fooled by that.

    「但,別被它騙了。

  • You've been given an incredible opportunity of growth.

    你得到了非常棒的成長機會。

  • Why?

    為什麼?

  • Because it's not like those pieces were scattered on earth

    因為並不是那些碎片散在地球各地,

  • and you have to go and pick them up.

    而你得去把它們撿回來。

  • No, those pieces fell into other people.

    不,那些碎片落到了其他人身上。

  • And only by sharing them you will become more complete.

    只有透過分享,你才會變得更完整。