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  • Supernovae are the most powerful explosions in  the universe, unleashing enough energy to outshine  

    超新星是宇宙中威力最大的爆炸,其釋放出的能量讓它們比星系

  • galaxies. We have no real metaphor for their power  – if the sun were to magically go supernova it  

    更加耀眼。對於它們的力量,我們無法比喻:假設太陽神奇的發生超新星爆發

  • would feel like you were being hit by the energy  of a nuclear explosion, every second. For weeks

    接下來好幾個星期內你每分每秒會覺得自己被核爆襲擊

  • While supernovae are the engines of creationforging the elements that enable life, they also  

    雖然超新星是創世的引擎,能夠鍛造出生命所需的元素,但它們也能使好幾個星系區域

  • burn sterile whole regions of galaxiesSo what would happen if one hit earth?

    無法孕育生命。那麼如果超新星爆發波及到地球會發生什麼事呢?

  • There are roughly speaking two ways to  make a supernova. Either the core of a  

    大略來說超新星可以由兩種方式觸發。要麼大質量恆星的核心塌陷

  • massive star implodes, or, less common, a  white dwarf gains mass to the point where  

    或較少見的,白矮星累積足夠的質量

  • it ignites explosive nuclear fusion. The  outcome is the same: a supernova explosion

    點燃了核融合之火。兩者的結果都一樣:超新星爆炸

  • If we think of an explosion on earth, we  think of something that happens fast and ends

    當在想像地球上的爆炸時,我們想到的都過程短暫

  • But a supernova is more like a volcanic  eruption followed by a tsunami. At first  

    但超新星更像是火山爆發并繼發海嘯

  • there is a colorful ball of hot, expanding gascreating a spectacular cloud that will shine for  

    爆炸起初有一團色彩繽紛的膨脹熱氣,創造了一個將閃耀一個月左右的

  • about a monthbut then it doesn’t stop. Hot  and dangerous gas rushes outward at speeds of  

    壯觀雲朵,但那之後還未結束。炙熱且危險的氣體以每秒一萬公里的速率

  • 10,000 km/s through the near vacuum of spacesweeping up the sparse gas of the galaxy.  

    在近真空中向外衝出,將星系中的稀疏氣體帶走

  • This wall of gas expands for tens of thousands  of years and will eventually span up to dozens  

    這個氣體牆將膨脹好幾萬年,最終達數十光年寬廣

  • of light-years until it finally cools off, and  disperses its substance back into the galaxy

    直到它最後冷卻下來,將其物質發散回星系之中

  • So what if this star tsunami hits us? Wellthe damage depends on how far away it is.

    要是這超新星海嘯襲捲到我們怎麼辦?所受傷害按距離分階段而定

  • Stage 1: Thousands of Light Years away 

    第一階段:數千光年外

  • Humans have witnessed dozens of supernovae but  all of them were thousands of lightyears away.  

    人類已見證了數十次超新星,但它們皆離地球數千光年以外

  • They appeared as new stars, some outshining  the moon, twinkling for a few weeks and  

    這些爆炸看似新星,有的比月亮還耀眼,閃耀了數週後消失

  • disappearing. Aside from looking very pretty  at this distance they don’t do much to us.

    在這距離,這些爆炸除了看起來很漂亮以外不會對我們造成什麼影響

  • Stage 2: 300 Light Years away Things begin to get a tiny bit  

    第二階段:三百光年外

  • icky once a supernova occurs around 300  lightyears away. We can expect one this  

    當超新星離我們約三百光年遠時

  • close to us every few million years:  a single star giving the night sky  

    事態會開始變的有一丁點討人厭。我們預計這類爆炸

  • an eerie glow like twilight. And while this  is far and dim enough not to do harm to us,  

    每數百萬年會發生一次:有顆恆星會在夜空中發出

  • they can affect the earth. At these distances  it is like being hit by the last weak waves  

    如暮光般詭異的光芒。雖然它很遠且亮度不高,無法對我們造成傷害

  • of the star tsunami. Not strong enough  to do real damage but still noticeable

    但仍能影響地球。在這距離,地球像被超新星海嘯的最終微弱波浪

  • In fact, we know that over the past 10 million  years multiple supernovae have struck Earth from  

    襲擊。雖然無法造成實際傷害,但仍有顯眼的效果

  • these distances because we can find radioactive  isotopes of iron deep in the rocks and sediments  

    實際上,我們知道在過去一千萬年裡,有好幾次超新星

  • at the bottom of the ocean. Amazingly, these  supernovae around the solar system have cleared a  

    從這個距離襲擊到地球,因為我們能在海底的岩石和沉澱物深處

  • 1000 light-year wide pocket of space that is  called the 'Local Bubble'. They blew away the  

    找到鐵的放射性同位素。很驚人的,這些在太陽系周遭的超新星

  • interstellar gas and dust, creating a lumpy wall  of gas that is now a cradle for star formation.

    形成了一個一千光年寬、被稱為「本地泡」的空間口袋。它們吹散了

  • Stage 3: 150 Light Years Away Once a supernova happens much closer  

    星際氣體與塵埃,形成一塊狀的氣體牆,現在是恆星誕生的搖籃

  • than 300 light-years, were approaching  the zone where it does real damage

    第三階段:一百五十光年外

  • Stars have extremely powerful magnetic fieldsWhen they die, the tsunami of dead star actually  

    當超新星爆炸發生在離三百光年更近的地方時,我們開始進入會造成實際傷害的階段

  • retains a lot of this magnetic energy, woven  through the shockwave that expands outwards.  

    恆星有著極強大的磁場。當恆星爆炸並釋放出衝擊波海嘯時

  • In this highly magnetized cloudwe get conditions like in a huge  

    大量的磁能仍殘留在內,被編織於向外擴展的衝擊波中

  • particle accelerator that is accelerating  charged particles like protons, nuclei,  

    在這高度磁化雲裡,它的環境條件

  • and electrons to immense speeds. Which means we  have an expanding cloud that is shooting deadly  

    如大型粒子對撞機,把帶電粒子如質子、原子核和電子加速到

  • radiation in all directions, long after the bright  light from the initial explosion has faded away

    極大的速率。換句話說在最初爆炸的明亮光線消失很久之後

  • If a supernova happens too close by, waves  of thesecosmic rayswill wash over the  

    我們有團能全方位放射出致命輻射的擴大雲

  • solar system for thousands of years. While  were mostly protected on earth’s surface  

    假設超新星觸發地點離我們太近,這些宇宙射線波會衝擊我們的

  • by the atmosphere and ozone layer, the influx  of extra radiation will still increase cancer  

    太陽系上千年。雖然我們在地球表面主要

  • and mutation rates. Not enough to causemass extinction but it will be noticeable

    受到大氣層和臭氧層的保護,這些額外輻射的湧入仍會增加癌症

  • Spaceflight would become  impossible in the solar system,  

    罹患率和突變率。雖不足以造成大滅絕,但還是有顯著的效果

  • as astronauts would not survive  the waves of radiation for long.  

    在太陽系中太空飛行會變成不可能的事情

  • We don’t know exactly how bad this would  be, but a supernova that is close enough may  

    因為宇航員沒辦法在輻射波裡長期存活

  • trap our species on earth for generations, maybe  thousands of years. It only gets worse from here.

    我們不知道情況具體會有多糟,但一足夠近的超新星可能會把我們的物種

  • Stage 4: Closer than 100 light years Within 100 light years, things get bad,  

    困在地球上好幾個世代,甚至可能上千年。接下來的階段只会更糟糕

  • as a supernova disrupts our climate in  ways that we don't fully understand yet.  

    第四階段:一百光年內

  • There are a few unpleasant things  happening all one after another

    在一百光年內的距離,事態變得相當惡劣,因為超新星會以我們尚未完全理解的方式擾亂我們的氣候

  • First, the high energy photons arrive from the  explosion, followed by many decades of radiation  

    一些不愉快的事情接連發生

  • from the radioactive tsunami, both of which  seriously damage the ozone layer, earth’s shield  

    首先,從爆炸處抵達地球的高能光子,以及接下來幾十年的

  • against harmful radiation. The ozone layer absorbs  ultraviolet radiation by breaking apart ozone, O3,  

    放射性海嘯,兩者皆嚴重破壞地球抵禦

  • into O2 and a free oxygen atom, which later  reforms back into another ozone molecule.  

    有害輻射的屏障:臭氧層。臭氧層透過把臭氧分子分解成氧分子和自由氧原子的方式來

  • But the supernova radiation breaks up Nitrogen  molecules that gobble up the free oxygen,  

    吸收紫外線輻射。隨後自由氧原子再和氧分子合併回臭氧分子

  • breaking the cycle and depleting the ozone  layer quickly: Without a radiation shield  

    但超新星的輻射會分解氮分子。分解出的氮原子會和自由氧原子結合

  • everybody living on the surface is exposed  to very high levels of UV radiation from our  

    因此打破了原本的循環並迅速消耗臭氧層。一旦沒了這道輻射屏障

  • suncancer rates would skyrocket and just going  outside during the day could be life threatening

    住在地表上的大家將被曝露在來自太陽的高水平紫外線輻射下

  • The extra radiation would also kill a lot, if not  most of the plankton in the oceans that live near  

    癌症罹患率會飆升。單單在白天外出可能是件危及生命的事情

  • the surface and are the basis for the marine  food chainsleading to a mass extinction

    額外的輻射也會殺死很多,如果不是大部分生活在海洋表面附近的

  • Worse still supernova radiation would ionize gas  in the atmosphere, which means that it would punch  

    浮游生物。作為海洋食物鏈的基礎,它們的死亡將導致大規模滅絕

  • through molecules and knock electrons off nucleileaving them charged. These charged nuclei then  

    更糟的是,超新星輻射會將大氣的空氣離子化,這代表那些輻射

  • act as seeds for water vapor to gather and form  massive global clouds. In the worst case they  

    會穿透分子,並把電子從原子核敲出,使它們帶電。這些帶電的原子核

  • would reflect enough sunlight to trigger an ice  age. In fact, it's thought that the ice age 2.5  

    會充當水蒸氣的種子,將它們聚集起來形成巨大的全球雲。最糟情況下

  • million years ago was caused by a supernova. Some  scientists even think that a supernova about 60  

    它們能反射足夠的陽光觸發冰河時期。實際上,人們認為兩百五十萬年前的冰河時期

  • light years away might have been the cause for the  Devonian mass extinction 350 million years ago.

    就是因為超新星造成的。有的科學家甚至認為三點五億年前的泥盆紀後期滅絕事件

  • But wait, there is more. The electrons punched  free by the radiation, form enormous electric  

    可能是由在六十光年外的超新星所觸發的

  • avalanchesor in other words: lightning. Earth  is hit by some of the worst thunderstorms in  

    但等等,災難還沒完呢。那些被輻射擊出的電子會形成巨大的電崩流

  • millions of years. The intense lightning causes  global wildfires that consume forests and crops,  

    換句話說,閃電。地球將遭受數百萬年來最嚴重的雷電風暴

  • devastate cities, disrupt our electrical  grids and global supply chain. All while  

    強烈閃電所導致的全球野火會燒毀森林和農作物

  • a decimated ozone layer leaks deadly radiation. While in the past, the ecosystem may have bounced  

    破壞城市、干擾我們的電網和全球供應鏈

  • back from a nearby supernova after a few thousand  or million years, there’s no guarantee modern  

    與此同時被破壞的臭氧層洩漏致命的輻射。雖然在過去,生態系統可能在

  • civilization can take a hit of this magnitudeFood shortages, skyrocketing prices, and wars,  

    幾千或幾百萬年後從附近的超新星中恢復過來,但不能保證

  • as nations struggle to not be consumed by chaos. So a supernova this close would at the very least  

    現代文明能夠承受如此大規模的打擊。我們將面臨糧食短缺、物價飆升和戰爭

  • do significant damage for hundreds or thousands  of years, if not end our modern civilization, and  

    各國將努力不被混亂所吞噬。換句話説一個如此近的超新星

  • with it millions or even billions of lives. Stillhumanity would likely survive and could recover.

    如果沒有結束我們的現代文明並奪走數百萬甚至數十億的生命

  • Stage 5: Closer than 25 light years A supernova closer than 25 light years  

    那它至少會在接下來幾百或幾千年造成重大的傷害。話雖如此,人類有可能會倖存下來並得以恢復

  • means that were in itskill radiuswhere  a mass extinction is all but guaranteed.  

    第五階段:二十五光年內

  • Probably about half of the ozone layer would  be destroyed, and massive climatic disruption  

    一個二十五光年内的超新星表示我們在它的「殺傷半徑」内,這也代表大滅絕幾乎保證會發生

  • on a scale we have never witnessed would ravage  earth. Entire ecosystems would swiftly be wiped  

    大概一半的臭氧層可能會被破壞,以及前所未見的

  • out by radiation, as global wildfires envelop the  planet. All the things described before happen,  

    大規模氣候破壞可能會蹂躪地球。整個生態系統將迅速被輻射

  • but way more intensely and much faster. A few  people might survive for years in bunkers,  

    抹滅,全球野火將吞噬整個星球。我們之前所描述的事情

  • if they have food supplies, but the world  they return to will be devastated and  

    會更加劇烈且快速的發生。如果有食物供應的話,有些人

  • hostile to life for hundreds of thousands of  years. Human extinction is extremely likely.

    可能有辦法在掩體中存活幾年,但他們所回到的世界將被摧殘且

  • Final stage: 4 light years Being any closer to a supernova is very  

    在接下來數十萬年對生命充滿敵意。人類滅絕極有可能發生

  • unlikely because space is big. But the effects  would be extreme. Even from 4 light years away,  

    最終階段:四光年內

  • the distance to Alpha Centauri, a supernova would  be almost as bright as the sun in the sky. While  

    要我們離超新星更接近是不太可能的事情,因爲宇宙很大

  • casting two shadows could be fun for a few hourswithin days the earth’s surface gets as hot as a  

    但我們所受到的影響將非常極端。即使從四光年外

  • sauna, baking the surface for weeks until the  explosion fades. The surface of earth burns,  

    等同於到南門二的距離,一顆超新星將幾乎和太陽一樣明亮

  • scoured of life. Even the oceans aren't  safe: the massive amount of radiation  

    雖然投射兩個影子可能會很有趣幾個小時,地表在幾天内會和三溫暖一樣熱

  • that follows burns away the ozone layerkilling everything that sees sunlight

    烘烤著地面數週,直到爆炸消退。地球表面將熊熊燃燒

  • It would be the largest extinction event in  history, reducing life to a few survivors  

    毫無生機。甚至連海洋都不安全:隨後到來的大量輻射

  • in the deep sea and critters in the deep  soil. Life basically has to start over.

    將燒毀臭氧層並消滅任何見到陽光的生物

  • Conclusion: How worried do you need to be? So should you worry? No! Fortunately,  

    這會是史上最大的滅絕事件,生命將只剩下少數

  • there are only a handful of stars that may explode  within 1000 lightyears of earth and none are close  

    在深海的倖存者和在深層土壤的小動物。生命基本上必須重來

  • enough to be a serious threat. Even better, these  stars will probably not go supernova for many  

    總結:你應該多擔心?

  • millions of years. So you are safe. But there’s  no guarantee for the far future. As stars orbit  

    所以你需要擔心嗎?不!幸運的是

  • the galaxy, our descendants may find themselves  dangerously close to a supernovabut by then  

    只有幾顆恆星會在離地球一千光年内爆炸,且沒有一個足夠接近

  • a far more advanced and wiser humanity will  hopefully be able to just move out of the way

    以構成嚴重威脅。更棒的是,這些恆星可能在接下來好幾百萬年内都不會

  • In any case, you can sleep well  tonight under the beautiful night sky.

    變成超新星。所以你是安全的。但在遙遠的未來就不好説了。隨著恆星

  • And if you dream about understanding the physics  behind this video and othersweve created a  

    環繞星系,我們的後代可能會發現自己危險地接近超新星。但到時候

  • series of lessons to build your understanding  of fundamental science. Made in collaboration  

    希望更加先進且賢明的人類能夠從那裏搬離

  • with our friends at Brilliant, these lessons dive  deeper into topics from our most popular videos,  

    無論如何,今晚你可以在這美麗的夜空下安穩地睡着

  • including things like cosmologybiology, and even climate science.

    如果你夢到自己在嘗試理解本期和其他視頻背後的物理原理,我們製作了

  • Brilliant is an interactive learning  tool that makes science accessible with  

    一系列課程幫助你建立對基礎科學的了解。這些

  • a hands-on approach. Because we know that to  really learn something, youve got to do it.  

    和在Brilliant的朋友們合力製作的課程深入探索我們熱門視頻的主題

  • Think of each lesson as a one-on-one  tutoring version of a Kurzgesagt video.

    例如宇宙學、生物學、甚至氣候科學等

  • In our latest lesson, youll journey  further into the conditions that can  

    Brilliant是個通過動手的方法使科學變得容易的

  • trigger a supernova and how to determine  the impact of one on a planet like ours.

    互動學習平台。因為我們知道要真正學習某事物,你必須自己動手做

  • Brilliant has thousands of lessons to explorefrom  math-based topics like algebra and probability to  

    把每個課程當作是一對一的指導版Kurzgesagt視頻

  • the concepts behind machine learning and quantum  computing. And with new lessons added each month,  

    在我們最新的課程裡,你會更深入理解觸發

  • including ones from Kurzgesagt, youll  always find something fascinating to learn.

    超新星的條件,並衡量它對像地球這類星球的影響

  • To get hands-on with Kurzgesagt lessons now, go  to Brilliant.org/nutshell and sign up for free.  

    Brilliant有上千堂課程,從數學方面的課題如代數和概率

  • And with a free trial of Brilliant Premiumyou can explore everything Brilliant has to  

    到機器學習和量子計算背後的概念,任會員探索。且隨著每個月包括Kurzgesagt在内的

  • offer. There’s even an extra perk for Kurzgesagt  viewers: the first 200 people to use the link  

    新課程發布,你總能找到一些有趣的東西來學習

  • get 20% off their annual membership, which  unlocks all of Brilliant’s courses in math,  

    想現在動手學習Kurzgesagt的課程,上Brilliant.org/nutshell免費註冊

  • science, and computer science. We love to go above and beyond with  

    通過免費試用Brilliant Premium,你能探索所有Brilliant的

  • our researchBrilliant will be the catalyst  to expand the limits of your knowledge.

    課程。Kurzgesagt觀眾更能享受特殊優惠:首兩百位使用這個連結

Supernovae are the most powerful explosions in  the universe, unleashing enough energy to outshine  

超新星是宇宙中威力最大的爆炸,其釋放出的能量讓它們比星系

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