TED演講者：Jessie Christiansen / 杰西·克里斯琴森

演講標(biāo)題：What the discovery of exoplanets reveals about the universe / 系外行星的發(fā)現(xiàn)揭示了宇宙的什么

內(nèi)容概要：What are the planets outside our solar system like? Astrophysicist and TED Fellow Jessie Christiansen has helped find thousands of them (and counting), and the variety is more wonderful and wild than you might imagine. She shares details on the trends emerging from the data -- including the intriguing possibility of "super-Earths" -- and what the discovery of exoplanets means for existential questions like: Where do we come from, and how did we get here?

我們太陽系之外的行星是什么樣子的？天文物理學(xué)家、TED Fellow 杰西·克里斯琴森（Jessie Christiansen）參與發(fā)現(xiàn)了幾千顆系外行星（數(shù)字還在不斷增長），琳瑯滿目，比你想象的更奇幻、更不羈。她詳細(xì)分享了數(shù)據(jù)展現(xiàn)的趨勢，包括“超級地球”神秘的存在，以及系外行星的發(fā)現(xiàn)與存在問題有什么關(guān)系，比如：我們從哪里來？我們又是如何到達此處的？

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【1】I am a planet hunter and keeper of the keys at NASA's Exoplanet Archive.

我是個行星獵人, 也是 NASA（美國航空航天局） 系外行星檔案的鑰匙保管人。

【2】In March 2022, we reached a major milestone in space exploration: 5,000 known exoplanets.

2022 年 3 月,我們達成了 太空探索的一個重要成就: 5000 個已知系外行星。

【3】For thousands of years, we've wondered about planets outside of our solar system, now called exoplanets.

幾千年以來, 我們都想了解 太陽系以外的行星, 如今被稱為“系外行星”。

【4】But our technology only recently caught up with our imaginations.

但是直到最近,我們的科技 才趕上了我們的想象。

【5】And yes, 5,000 planets is incredible.

沒錯,5000 顆行星 是個驚人的數(shù)目。

【6】What's even more incredible is how space research will change as a result.

更驚人的是 它為太空研究帶來的改變。

【7】When I started grad school, there were about 100 known exoplanets, all radically different from the Earth and from each other.

我開始讀研究生時, 大約有 100 個已知系外行星, 全部與地球大相徑庭, 各不相同。

【8】I was determined to find more.

我下定決心要找出更多。

【9】I spent four years looking at nearly 87,000 stars, one by one.

我花了四年,逐一觀察 87000 顆恒星。

【10】Now you might have this romantic idea that I was gazing intently through a telescope, pondering some gorgeous view of the universe.

你可能會腦補 這樣一個浪漫的場景, 我專心致志地 透過望遠(yuǎn)鏡凝視星空, 徜徉在宇宙的美景中。

【11】I was not.

并不是。

【12】I was looking at data like this, measuring the brightness of each star over time.

我看的是這種數(shù)據(jù), 持續(xù)測量每顆恒星的亮度。

【13】If the brightness dipped, just briefly, just a little bit, it could be because a planet had orbited in front of that star, blocking some of the light from reaching my telescope.

如果亮度降低,即使是一瞬, 即使是少許, 都有可能是因為有一顆行星 運行到了這顆恒星前方, 擋住了射向望遠(yuǎn)鏡的部分光線。

【14】So I spent four years looking for decimal-level changes in these data.

我花了四年尋找數(shù)據(jù)中 微乎其微的變化。

【15】And after four years, I'd found ...

過了四年,我發(fā)現(xiàn)了……

【16】nothing.

啥都沒發(fā)現(xiàn)。

【17】Zero exoplanets.

0 個系外行星。

【18】Thankfully, they still gave me the PhD, I think, for effort.

好在他們還是給了我博士學(xué)位。 我猜是因為沒有功勞也有苦勞。

【19】Then I moved to Harvard, where I worked on my first NASA mission, called EPOXI.

然后我去了哈佛,開始了我的第一個 NASA 任務(wù),名為 EPOXI。

【20】I still didn't find any exoplanets.

我還是沒發(fā)現(xiàn)任何系外行星。

【21】Then in March 2010, I joined the Kepler Mission, NASA's grand experiment with putting one of our planet-hunting instruments into space.

2010 年 3 月, 我加入了開普勒任務(wù), NASA 的一個重大任務(wù), 將一臺探索行星的儀器 發(fā)射進太空。

【22】Monday was my first day on the base in Silicon Valley.

星期一是我進入硅谷基地 工作的第一天。

【23】It was mostly spent in HR.

基本上都在處理人事手續(xù)。

【24】Tuesday, I sat down and looked at the data for the first time, and I found my first exoplanet.

星期二,我第一次坐下查看了數(shù)據(jù), 就找到了我的第一顆系外行星。

【25】A few minutes later, I found another one.

幾分鐘后,我又找到了一顆。

【26】There's a saying that we're the generation that was born too late to explore Earth and too soon to explore space.

有人說,我們這一代人, 探索地球為時已晚, 探索太空為時尚早。

【27】That's not true anymore.

這種說法已經(jīng)過時了。

【28】That day and every day since, I've gotten to explore space.

那一天及自此的每一天, 我都在探索太空。

【29】Kepler made it possible for us to measure stellar brightness much more precisely than we had before.

開普勒讓我們可以 以前所未有的精度 測量恒星亮度。

【30】And eventually I helped find thousands of exoplanets.

我最終得以參與發(fā)現(xiàn) 幾千個系外行星。

【31】And we've really only searched our local corner of the galaxy to find those planets.

而且我們只搜索了 銀河系里我們眼前的一隅, 就發(fā)現(xiàn)了這些系外行星。

【32】That means there's likely tens of billions of planets just in our Milky Way.

意味著僅僅在我們的銀河系中, 就有可能存在幾百億顆行星。

【33】Now with so much data, we can start sorting and grouping and categorizing these planets to find trends.

有了這么多數(shù)據(jù), 我們開始整理、 合并、分類這些行星, 尋找趨勢。

【34】Think of it this way: if you wanted to learn about dogs and you had five dogs in your study, well, you'd learn a lot about those five dogs.

可以這么理解: 如果你想了解狗, 你的研究中包含了五條狗, 那你就能充分了解 這五條狗的情況。

【35】That they're all good dogs.

了解到它們都是好狗。

【36】But maybe not about dogs in general.

但是你可能無法得出 狗的宏觀情況。

【37】If you had 5,000 dogs in your study, then you'd start to see that there were German Shepherds and Dobermanns and beagles, and that these different breeds have different features.

如果研究包含了五千條狗, 你就能看出其中有 德國牧羊犬、杜賓犬、 比格犬, 每個品種都有不同的特點。

【38】With demographic-level data on exoplanets, we can start asking some of these big questions for the first time, like: Of those thousands and billions of planets in our galaxy, how many are like the Earth, or like Jupiter?

有了系外行星 具體特征的數(shù)據(jù), 我們終于能問出一些 更宏大的問題, 比如:在銀河系 這上億的行星中, 有多少個類似地球,類似木星？

【39】How many planets does a typical star have?

一顆恒星通常有多少顆行星？

【40】Can a planet orbit more than one star?

行星能否圍繞不止一顆恒星運行？

【41】Yes.

可以。

【42】Can a planet exist without any star at all?

不依靠恒星,行星還能存在嗎？

【43】Also yes.

答案也是可以。

【44】One surprising result from the study of planet populations is that the most common kind of planet in our galaxy might be one we don't have in our solar system: a super-Earth up to twice as big and ten times as heavy as our Earth.

行星樣本研究 帶來了一個驚人的結(jié)果: 我們銀河系中最常見的一種行星 可能是我們的太陽系中 不存在的一種行星 地球兩倍大、 十倍重的超級地球。

【45】We've found evaporating planets, disintegrating planets, planets clustered together in a clockwork dance, ultra-puffy planets, ultra-dense planets.

我們還發(fā)現(xiàn)了蒸發(fā)行星、 解體行星、 以機械運轉(zhuǎn)形態(tài) 聚在一起的行星、 過度膨脹的行星、 過度緊縮的行星。

【46】It's truly a wild and wonderful menagerie that I get to corral at the NASA Exoplanet Archive.

在我打開 NASA 系外行星檔案的柵欄時, 涌向我的是無拘無束、 無與倫比的自由生命。

【47】But it gets even more interesting than that.

但是有意思的地方不止于此。

【48】With so much data, we might finally be able to figure out how planets are made.

手握這么多數(shù)據(jù),我們終于 有機會搞明白行星的起源了。

【49】We see baby stars being born in stellar nurseries surrounded by dust and gas.

我們知道原恒星誕生于 充滿宇宙塵埃和氣體的恒星搖籃。

【50】And we see all the stars surrounded by completed planetary systems.

我們也知道所有恒星 都由完全形成的行星系統(tǒng)環(huán)繞。

【51】But we still don't really know what happens in between.

但是我們依舊不知道 這之間發(fā)生了什么。

【52】With more data, we might find planets at some middle stage or many middle stages.

如果有了更多的數(shù)據(jù), 我們就有可能發(fā)現(xiàn) 處在某個或某些中間階段的行星。

【53】And from there, be able to map out a timeline of planetary development.

接著我們就能描繪出 行星演變的整個過程。

【54】What triggers these diffused clouds of dust and gas to collapse and transform?

是什么導(dǎo)致了這些四處彌漫的 塵埃和氣體團分解、變形？

【55】And how does the chaos and turmoil of dust become pebbles, and pebbles become boulders, and boulders become planetesimals?

塵埃是如何經(jīng)過風(fēng)云巨變 變成卵石的, 卵石是如何變成巨石的, 巨石是如何變成星子的？

【56】And from there, after an intense series of bombardments eventually settle into an ordered series of planets.

緊接著, 在一系列猛烈的撞擊之后, 最終形成了有序的行星。

【57】How often is one of those planets solid and warm, with a water ocean lapping a sandy shore?

有多少概率出現(xiàn)一個 堅固、溫暖的行星, 還有液體海洋 拍打著沙質(zhì)海岸呢？

【58】Where do we come from, and how did we get here?

我們從哪里來, 我們又是怎么來的呢？

【59】The more we learn about exoplanets, the easier it is to target the ones we want.

我們越了解系外行星, 就越容易找到我們想要的目標(biāo)。

【60】So far, we haven't found any planets that are like the Earth.

直至目前,我們還沒有發(fā)現(xiàn) 任何類似于地球的行星。

【61】But I hope we will.

但是我希望我們能發(fā)現(xiàn)。

【62】NASA just spent the last few years studying the idea of a very large telescope in space with next-generation technology that would allow us to take an image, an actual photograph, of a planet like the Earth.

NASA 在過去的幾年里, 一直在研究超巨型太空望遠(yuǎn)鏡, 搭載新一代技術(shù), 讓我們能夠拍下一張照片, 為類似地球的行星 拍下一張真實的照片。

【63】With that photo, we could search for biomarkers, signatures of life.

有了這張照片,我們就能 探索生物標(biāo)記物,即生命的跡象。

【64】I'll probably spend the rest of my career working on that mission.

我也許會將我余下的職業(yè)生涯 奉獻給這個任務(wù)。

【65】I hope I get to take that photo.

我希望我能拍到這張照片。

【66】Thank you.

謝謝。