字幕列表 影片播放 列印所有字幕 列印翻譯字幕 列印英文字幕 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 creation, forging 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 galaxies. So 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 gas, creating 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 month – but 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 space, sweeping 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? Well, the 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, we’re approaching the zone where it does real damage. 第三階段:一百五十光年外 Stars have extremely powerful magnetic fields. When 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 cloud, we 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 these ‘cosmic rays’ will 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 we’re 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 cause a mass 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 sun – cancer 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 chains – leading 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 nuclei, leaving 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 avalanches – or 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 magnitude. Food 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. Still, humanity 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 we’re in its ‘kill radius’ where 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 hours, within 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 layer, killing 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 supernova – but 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 others–we’ve 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 cosmology, biology, 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, you’ve 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, you’ll 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 explore—from 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, you’ll 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 Premium, you 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 research –Brilliant 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
B2 中高級 中文 新星 輻射 地球 爆炸 恆星 階段 The Most Extreme Explosion in the Universe 13 0 林宜悉 發佈於 2022 年 09 月 22 日 更多分享 分享 收藏 回報 影片單字