Sara Seager: The search for planets beyond our solar system

112,757 views ・ 2015-05-28

TED


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譯者: Yamei Huang 審譯者: Coco Shen
00:12
I'm here to tell you about the real search for alien life.
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在這裡我要告訴各位一個有關 探尋外星生命的真實故事。
00:16
Not little green humanoids arriving in shiny UFOs,
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我所說不是長得像人的綠色小個子 乘坐發光飛碟抵達地球,
00:19
although that would be nice.
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儘管那個主題也很好。
00:21
But it's the search for planets orbiting stars far away.
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我們在找尋的是 繞行恆星的遠方行星。
00:25
Every star in our sky is a sun.
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天空中每一顆恆星都是一個太陽。
00:27
And if our sun has planets --
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如果我們的太陽有行星
00:29
Mercury, Venus, Earth, Mars, etc.,
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如水星、金星、地球、火星等等,
00:31
surely those other stars should have planets also,
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當然那些其他恆星也應該有行星,
00:34
and they do.
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它們確實有行星。
00:35
And in the last two decades,
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在過去的二十年,
00:36
astronomers have found thousands of exoplanets.
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天文學家已發現數千顆系外行星。
00:40
Our night sky is literally teeming with exoplanets.
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夜晚的天空幾乎佈滿系外行星。
00:43
We know, statistically speaking,
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依據統計,我們知道,
00:44
that every star has at least one planet.
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每顆恆星至少有一顆行星。
00:47
And in the search for planets,
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在探尋行星中,
00:49
and in the future, planets that might be like Earth,
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未來,行星或許像地球一樣,
00:52
we're able to help address
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我們能夠提出
00:54
some of the most amazing and mysterious questions
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一些令人訝異且神秘的問題
00:57
that have faced humankind for centuries.
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這問題已經圍繞人類數百年之久。
00:59
Why are we here?
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我們為什麼在這裡?
01:01
Why does our universe exist?
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我們的宇宙為什麼存在?
01:03
How did Earth form and evolve?
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地球是如何形成與演變而來的?
01:05
How and why did life originate and populate our planet?
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生命的起源是什麼 我們為何生活在這顆星球上?
01:09
The second question that we often think about is:
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我們經常思考的第二個問題是:
01:12
Are we alone?
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我們獨立存在宇宙中嗎?
01:14
Is there life out there?
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有其他的生物存在嗎?
01:17
Who is out there?
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他們是誰?
01:19
You know, this question has been around for thousands of years,
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你知道, 這個問題已經圍繞人類數千年了,
01:22
since at least the time of the Greek philosophers.
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至少從古希臘哲學家那時候起 就已經有這個問題。
01:25
But I'm here to tell you just how close we're getting
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但此時我要告訴你 我們有多接近
01:27
to finding out the answer to this question.
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取得這個問題的答案。
01:30
It's the first time in human history that this really is within reach for us.
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這是人類史上的第一次
01:35
Now when I think about the possibilities for life out there,
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當我思索其他生物存在的可能性,
01:38
I think of the fact that our sun is but one of many stars.
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事實上太陽是眾多恆星之一。
01:42
This is a photograph of a real galaxy,
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這是一張真實銀河星系的照片,
01:44
we think our Milky Way looks like this galaxy.
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我們認為銀河就像這張照片。
01:47
It's a collection of bound stars.
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是由眾多恆星組成。
01:48
But our [sun] is one of hundreds of billions of stars
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太陽是千億恆星中的一員
01:53
and our galaxy is one of upwards of hundreds of billions of galaxies.
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我們的銀河是千億銀河中的一員。
01:58
Knowing that small planets are very common,
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我們知道小行星是非常普遍的,
02:01
you can just do the math.
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可以算得出來。
02:03
And there are just so many stars and so many planets out there,
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那裡有好多的恆星行星,
02:07
that surely, there must be life somewhere out there.
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必然一定有生物存在。
02:11
Well, the biologists get furious with me for saying that,
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生物學家 對我這樣的說法會非常生氣,
02:14
because we have absolutely no evidence for life beyond Earth yet.
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因為我們的確無法證明 地球之外有生物存在。
02:18
Well, if we were able to look at our galaxy from the outside
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如果我們能夠從外部觀察銀河系
02:23
and zoom in to where our sun is,
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將太陽的位置放大觀察,
02:26
we see a real map of the stars.
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我們看到一張真實的恆星地圖。
02:28
And the highlighted stars are those with known exoplanets.
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02:31
This is really just the tip of the iceberg.
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這只是冰山的一角。
02:34
Here, this animation is zooming in onto our solar system.
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這個動畫放大太陽系的位置。
02:38
And you'll see here the planets
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你會看到這些行星
02:40
as well as some spacecraft that are also orbiting our sun.
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和一些太空船一樣繞著太陽轉。
02:44
Now if we can imagine going to the West Coast of North America,
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想像我們到北美的西岸,
02:48
and looking out at the night sky,
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看著那裡的夜空,
02:50
here's what we'd see on a spring night.
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這就是當地春天的夜晚。
02:52
And you can see the constellations overlaid
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你可以看到佈滿星群
02:54
and again, so many stars with planets.
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同樣的,很多的恆星和行星。
02:57
There's a special patch of the sky where we have thousands of planets.
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天空有一特殊區塊 那裡有數千顆行星。
03:01
This is where the Kepler Space Telescope focused for many years.
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這是克卜勒太空望遠鏡 多年來關注的地方。
03:05
Let's zoom in and look at one of the favorite exoplanets.
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我們放大畫面 觀察其中一顆我們喜愛的系外行星。
03:10
This star is called Kepler-186f.
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這恆星被稱為克卜勒-186f。
03:14
It's a system of about five planets.
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是一個由五個行星組成的系統。
03:16
And by the way, most of these exoplanets, we don't know too much about.
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順道一提,大部分的系外行星 我們並不太了解。
03:20
We know their size, and their orbit and things like that.
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我們知道它們的大小, 運行軌道之類的。
03:23
But there's a very special planet here called Kepler-186f.
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有一個非常特別的行星 被稱為克卜勒-186f。
03:27
This planet is in a zone that is not too far from the star,
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這顆行星所在區域 距離恆星不遠,
03:31
so that the temperature may be just right for life.
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其溫度可能適合生物生存。
03:35
Here, the artist's conception is just zooming in
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這是藝術家的觀念,將畫面放大
03:38
and showing you what that planet might be like.
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向你們展示那顆行星的樣子。
03:43
So, many people have this romantic notion of astronomers
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因此, 很多人對天文學家有浪漫的想法
03:48
going to the telescope on a lonely mountaintop
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在一個孤寂的山頂 對著望遠鏡
03:52
and looking at the spectacular night sky through a big telescope.
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透過大的望遠鏡 觀察壯觀的夜空。
03:55
But actually, we just work on our computers like everyone else,
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但事實上,我們只是 和其他人一樣在電腦前忙碌,
03:59
and we get our data by email or downloading from a database.
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透過郵件或從資料庫下載 以取得資料。
04:03
So instead of coming here to tell you
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我不是跑到這裡來告訴你
04:05
about the somewhat tedious nature of the data and data analysis
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有點冗長乏味的資料和資料分析
04:08
and the complex computer models we make,
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以及我們做的複雜電腦程式,
04:10
I have a different way to try to explain to you
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我要以不同的方式向你們解說
04:13
some of the things that we're thinking about exoplanets.
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我們對系外行星的一些想法。
04:15
Here's a travel poster:
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這是一張旅行海報:
04:16
"Kepler-186f:
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「克卜勒-186f:
04:19
Where the grass is always redder on the other side."
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這草的顏色 總是比另一邊的草還要紅。」
04:22
That's because Kepler-186f orbits a red star,
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那是因為克卜勒-186f 繞著紅恆星運轉,
04:25
and we're just speculating that perhaps the plants there,
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我們只是推測那裡的行星,
04:28
if there is vegetation that does photosynthesis,
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如果有進行光合作用的植物,
04:31
it has different pigments and looks red.
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會有不同的色素 看起來是紅色。
04:34
"Enjoy the gravity on HD 40307g,
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「盡情享受 HD 40307g 的重力,
04:38
a Super-Earth."
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一顆超級地球。」
04:40
This planet is more massive than Earth
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這顆行星遠大於地球
04:42
and has a higher surface gravity.
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而且有較大地表引力。
04:44
"Relax on Kepler-16b,
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「在克卜勒-16b上放輕鬆
04:47
where your shadow always has company."
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影子在那裡成雙成對。」
04:49
(Laughter)
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(笑聲)
04:51
We know of a dozen planets that orbit two stars,
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我們知道繞著二顆恆星 運轉的十二顆行星,
04:55
and there's likely many more out there.
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那裡可能有更多的行星。
04:57
If we could visit one of those planets,
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如果我們能夠參觀其中一顆行星,
04:59
you literally would see two sunsets
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你幾乎可以看到二個日落
05:01
and have two shadows.
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和二個自己的影子。
05:03
So actually, science fiction got some things right.
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事實上, 科幻小說的故事有些是正確的。
05:05
Tatooine from Star Wars.
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星際大戰裡的塔圖因星
05:08
And I have a couple of other favorite exoplanets
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我還有我喜歡的外行星
05:10
to tell you about.
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要告訴你。
05:11
This one is Kepler-10b,
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這顆是克卜勒-10b,
05:13
it's a hot, hot planet.
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是一顆很熱的行星,
05:15
It orbits over 50 times closer to its star
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繞行就近的恆星超過五十次
05:18
than our Earth does to our sun.
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超過地球繞太陽的次數。
05:20
And actually, it's so hot,
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事實上,它的溫度很高
05:22
we can't visit any of these planets, but if we could,
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我們無法參觀任何這類的行星 如果可以的話,
05:25
we would melt long before we got there.
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在我們到達之前就已經融化。
05:27
We think the surface is hot enough to melt rock
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我們認為其表面溫度很高 足以融化岩石
05:29
and has liquid lava lakes.
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有液體熔岩湖。
05:31
Gliese 1214b.
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格利澤 1214b。
05:33
This planet, we know the mass and the size
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這顆行星,我們知道它的質量和體積
05:35
and it has a fairly low density.
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其密度極低。
05:36
It's somewhat warm.
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有溫暖的氣候。
05:38
We actually don't know really anything about this planet,
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事實上我們對這星球一無所知,
05:40
but one possibility is that it's a water world,
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但有一個可能性是 這顆行星是個水世界,
05:43
like a scaled-up version of one of Jupiter's icy moons
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像一顆放大版的木星冰冷衛星之一
05:46
that might be 50 percent water by mass.
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或許水就佔了質量的一半。
05:49
And in this case, it would have a thick steam atmosphere
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在這種情況下, 它有厚厚的大氣流,
05:52
overlaying an ocean,
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覆蓋著一片海洋,
05:54
not of liquid water,
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但不是液體形態的水,
05:55
but of an exotic form of water, a superfluid --
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而是異質形態的水,一種超級液體,
05:58
not quite a gas, not quite a liquid.
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不完全是氣態,不完全是液態。
06:00
And under that wouldn't be rock,
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在海洋下面並非岩石,
06:02
but a form of high-pressure ice,
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而是一種高壓冰的形態,
06:04
like ice IX.
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如同冰 IX。
06:06
So out of all these planets out there,
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在那些行星範圍之外的地方,
06:08
and the variety is just simply astonishing,
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其多樣性也令人驚訝,
06:12
we mostly want to find the planets that are Goldilocks planets, we call them.
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我們大部分想找的行星 是金髮星球行星。
06:17
Not too big, not too small,
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體積不太大,也不太小,
06:19
not too hot, not too cold --
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溫度不太熱,也不太冷,
06:20
but just right for life.
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剛好適合生物生存。
06:22
But to do that, we'd have to be able to look
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不過要做到這一點, 我們必須能夠
06:24
at the planet's atmosphere,
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觀察到這顆行星的大氣,
06:26
because the atmosphere acts like a blanket trapping heat --
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因為大氣就像一塊保溫地毯
06:28
the greenhouse effect.
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溫室效應。
06:30
We have to be able to assess the greenhouse gases
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我們必須能夠偵測到其他行星的
06:33
on other planets.
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溫室氣體。
06:35
Well, science fiction got some things wrong.
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這方面,科幻小說的描述有誤。
06:37
The Star Trek Enterprise
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「星艦迷航-企業號」
06:39
had to travel vast distances at incredible speeds
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必須以高速繞行其他行星
06:42
to orbit other planets
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做長距離旅行
06:44
so that First Officer Spock could analyze the atmosphere
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因此副艦長斯波克才能分析大氣
06:48
to see if the planet was habitable
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以看出該行星是否適合生物定居
06:50
or if there were lifeforms there.
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或者是否有生物存在。
06:52
Well, we don't need to travel at warp speeds
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我們不需要以極高速度行駛
06:55
to see other planet atmospheres,
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以取得其他其他行星的大氣資料,
06:57
although I don't want to dissuade any budding engineers
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雖然我不想去勸阻 新進工程師
07:00
from figuring out how to do that.
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去找到實踐這項工作的方法。
07:02
We actually can and do study planet atmospheres
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實際上我們可以 由地球軌道
07:04
from here, from Earth orbit.
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去研究那些行星的大氣。
07:06
This is a picture, a photograph of the Hubble Space Telescope
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這是哈柏望遠鏡的照片
07:09
taken by the shuttle Atlantis as it was departing
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由太空梭亞特蘭蒂斯號 返航時所拍攝的照片
07:12
after the last human space flight to Hubble.
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最後一次載人太空船到哈柏之後。
07:14
They installed a new camera, actually,
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他們在太空船上安裝新的照相機,
07:16
that we use for exoplanet atmospheres.
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可以用來收集外行星大氣資料。
07:18
And so far, we've been able to study dozens of exoplanet atmospheres,
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目前,我們已經能夠 研究數十個外行星大氣資料,
07:23
about six of them in great detail.
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其中六個有非常詳細的資料。
07:25
But those are not small planets like Earth.
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這些行星不像地球是個小行星。
07:27
They're big, hot planets that are easy to see.
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它們體積大且溫度高, 是容易觀察到的行星。
07:30
We're not ready,
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我們還沒準備好,
07:31
we don't have the right technology yet to study small exoplanets.
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我們沒有相當的技術 以研究小行星。
07:36
But nevertheless,
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儘管如此,
07:37
I wanted to try to explain to you how we study exoplanet atmospheres.
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我仍然想要向大家解釋 我們是如何研究外行星大氣。
07:41
I want you to imagine, for a moment, a rainbow.
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大家可以想像一下彩虹。
07:44
And if we could look at this rainbow closely,
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如果我們可近距離觀察彩虹,
07:47
we would see that some dark lines are missing.
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可以看到一些暗色線消失了。
07:51
And here's our sun,
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這是我們的太陽。
07:52
the white light of our sun split up,
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白色光分解了。
07:54
not by raindrops, but by a spectrograph.
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不是被雨滴,而是被光譜儀分解了。
07:56
And you can see all these dark, vertical lines.
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你可以看到這暗色垂直的線。
07:59
Some are very narrow, some are wide,
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有些非常窄,有些寬,
08:00
some are shaded at the edges.
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有些邊緣被遮住了。
08:02
And this is actually how astronomers have studied objects in the heavens,
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這就是天文學家 如何研究太空物質的方式,
08:06
literally, for over a century.
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這是過去一百年的研究方式。
08:07
So here, each different atom and molecule
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這張圖,每一原子和分子
08:10
has a special set of lines,
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各有特殊的頻譜線,
08:11
a fingerprint, if you will.
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你可以把它當作指紋,
08:13
And that's how we study exoplanet atmospheres.
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那就是我們利用這訊息 來研究外行星的大氣成份
08:15
And I'll just never forget when I started working
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我永遠忘不了 二十年前
08:18
on exoplanet atmospheres 20 years ago,
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剛開起研究外行星大氣的時候,
08:20
how many people told me,
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多少人告訴我,
08:21
"This will never happen.
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「這行不通。
08:22
We'll never be able to study them. Why are you bothering?"
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我們永遠無法做到。 為何費心在這種事上?」
08:25
And that's why I'm pleased to tell you about all the atmospheres studied now,
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那就是為什麼我很高興要告訴你們 目前所有有關的大氣研究,
08:29
and this is really a field of its own.
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它已成形了。
08:31
So when it comes to other planets, other Earths,
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當談及到其他行星, 其他類似地球行星,
08:33
in the future when we can observe them,
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將來我們可以觀察到,
08:35
what kind of gases would we be looking for?
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什麼是我們要尋找的氣體?
08:38
Well, you know, our own Earth has oxygen in the atmosphere
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你知道,地球的大氣
08:41
to 20 percent by volume.
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含有百分之二十的氧氣。
08:43
That's a lot of oxygen.
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含量很高。
08:45
But without plants and photosynthetic life,
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但若沒有植物及其光合作用。
08:48
there would be no oxygen,
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大氣中不會有氧氣。
08:49
virtually no oxygen in our atmosphere.
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事實上我們的大氣中沒有氧氣。
08:52
So oxygen is here because of life.
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因為生物的存在才有氧氣。
08:54
And our goal then is to look for gases in other planet atmospheres,
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我們目標就是尋找 其他行星大氣中的氣體,
08:58
gases that don't belong,
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氣體原本不存在,
09:00
that we might be able to attribute to life.
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或許我們可以歸功於生物。
09:02
But which molecules should we search for?
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我們在尋找哪些分子呢?
09:04
I actually told you how diverse exoplanets are.
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我告訴過各位外行星的種類很多。
09:07
We expect that to continue in the future
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未來會陸續發現更多
09:09
when we find other Earths.
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當我們發現其他類似地球的行星。
09:10
And that's one of the main things I'm working on now,
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這是我目前正在從事的最主要工作,
09:13
I have a theory about this.
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我有個自己的理論。
09:14
It reminds me that nearly every day,
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它幾乎每天提醒我,
09:17
I receive an email or emails
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我收到一封或多封郵件
09:19
from someone with a crazy theory about physics of gravity
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是對重力物理學理論
09:23
or cosmology or some such.
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或是宇宙論 提出瘋狂想法的人所寄來的。
09:25
So, please don't email me one of your crazy theories.
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所以請不要再給我發這種郵件了。
09:28
(Laughter)
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(笑聲)
09:29
Well, I had my own crazy theory.
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我有自己瘋狂的理論。
09:32
But, who does the MIT professor go to?
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麻省理工學院的教授要跟誰探討呢?
09:34
Well, I emailed a Nobel Laureate in Physiology or Medicine
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我向諾貝爾生理及醫學獎得主發信
09:38
and he said, "Sure, come and talk to me."
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他說,「好,我們討論一下。」
09:40
So I brought my two biochemistry friends
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我帶了二個 我的生物化學領域的朋友
09:42
and we went to talk to him about our crazy theory.
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要和他討論我們的瘋狂理論。
09:45
And that theory was that life produces all small molecules,
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那理論是,生命製造了所有小分子,
09:48
so many molecules.
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許許多多的分子。
09:50
Like, everything I could think of, but not being a chemist.
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所有我可以想得到的事情, 雖然我不是個化學領域專家。
09:53
Think about it:
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想想看:
09:54
carbon dioxide, carbon monoxide,
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二氧化碳,一氧化碳,
09:56
molecular hydrogen, molecular nitrogen,
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氫分子,氮分子,
09:58
methane, methyl chloride --
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甲烷,氯甲烷,
09:59
so many gases.
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等諸多氣體。
10:01
They also exist for other reasons,
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它們的存在也有其原因,
10:03
but just life even produces ozone.
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生物即可產生臭氧。
10:04
So we go to talk to him about this,
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所以我們和他談論這個主題,
10:06
and immediately, he shot down the theory.
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結果立刻被他否決。
10:09
He found an example that didn't exist.
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他找到一個不存在的氣體的例子。
10:11
So, we went back to the drawing board
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所以我們回去從頭做起
10:13
and we think we have found something very interesting in another field.
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我們發現在其他領域 非常有趣的東西。
10:17
But back to exoplanets,
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回到外行星這個話題,
10:18
the point is that life produces so many different types of gases,
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重點是生物製造各種不同的氣體,
10:21
literally thousands of gases.
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差不多有幾千種。
10:24
And so what we're doing now is just trying to figure out
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我們現在要做的是試著找出
10:26
on which types of exoplanets,
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外行星上有那些氣體,
10:28
which gases could be attributed to life.
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那些氣體是由生物產生。
10:34
And so when it comes time when we find gases
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當我們在外行星大氣中
10:36
in exoplanet atmospheres
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所找到的氣體
10:37
that we won't know if they're being produced
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不知道這些氣體是由
10:39
by intelligent aliens or by trees,
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外星人製造,或是樹木所產生,
10:42
or a swamp,
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或是由沼澤產生。
10:44
or even just by simple, single-celled microbial life.
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或是來自單細胞生物。
10:47
So working on the models
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所以有了一些模型
10:49
and thinking about biochemistry,
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以生物化學思考,
10:50
it's all well and good.
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會有好的結果。
10:52
But a really big challenge ahead of us is: how?
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但面臨最大的挑戰是: 如何做?
10:54
How are we going to find these planets?
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要如何找到這些行星?
10:57
There are actually many ways to find planets,
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其實有許多方法找到行星。
10:59
several different ways.
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許多不同的方法。
11:00
But the one that I'm most focused on is how can we open a gateway
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不過我把焦點放在 我們如何何開啟一個通道
11:04
so that in the future,
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在未來,
11:05
we can find hundreds of Earths.
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我們可以找到數百個地球。
11:07
We have a real shot at finding signs of life.
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我們確實已著手找尋 有生命跡象的生物。
11:10
And actually, I just finished leading a two-year project
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我剛完成一個 由我負責的二年專案
11:13
in this very special phase
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在這個特殊的專案中
11:15
of a concept we call the starshade.
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有一個我們稱為遮星板的概念。
11:18
And the starshade is a very specially shaped screen
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遮星板是一個形狀非常特殊的螢幕
11:21
and the goal is to fly that starshade
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把遮星板送至外太空
11:23
so it blocks out the light of a star
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它可遮恆星的光
11:26
so that the telescope can see the planets directly.
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因此可以透過望遠鏡直接看到行星。
11:29
Here, you can see myself and two team members
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這張圖可以看到我和二位團隊成員
11:31
holding up one small part of the starshade.
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拿著遮星板的一小部分。
11:33
It's shaped like a giant flower,
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它的形狀就像朵巨大的花,
11:35
and this is one of the prototype petals.
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這是一片花瓣的雛型。
11:38
The concept is that a starshade and telescope could launch together,
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這個概念是 遮星板和望遠鏡可以一同送到太空,
11:43
with the petals unfurling from the stowed position.
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然後從存放位置打開花瓣
11:46
The central truss would expand,
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中心的花束會展開,
11:48
with the petals snapping into place.
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花瓣迅速到達特定位置。
11:52
Now, this has to be made very precisely,
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這過程要做到非常準確,
11:54
literally, the petals to microns
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這花瓣要達微米的精確度
11:55
and they have to deploy to millimeters.
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部署要達毫米精確度。
11:58
And this whole structure would have to fly
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這整個架構必須送到
12:00
tens of thousands of kilometers away from the telescope.
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距離望遠鏡數萬公里的地方。
12:04
It's about tens of meters in diameter.
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它的直徑有幾十公尺。
12:06
And the goal is to block out the starlight to incredible precision
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目的是這個難以置信的精確度 要去遮擋恆星的光線
12:11
so that we'd be able to see the planets directly.
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這樣我們就可以直接觀察行星。
12:15
And it has to be a very special shape,
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它的形狀必須很特殊,
12:17
because of the physics of defraction.
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因為繞射現象。
12:19
Now this is a real project that we worked on,
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這是我們做的一個專案,
12:21
literally, you would not believe how hard.
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你無法想像這有多難。
12:24
Just so you believe it's not just in movie format,
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這不是一個電影情節
12:26
here's a real photograph
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這是一張真實的照片
12:28
of a second-generation starshade deployment test bed in the lab.
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實驗室裡第二代 遮星板測試平台。
12:33
And in this case, I just wanted you to know
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在這個專案中, 我只是想讓你們知道
12:35
that that central truss has heritage left over
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花的中心點
12:38
from large radio deployables in space.
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由太空中大範圍展開的無線電設備 所留下來。
12:41
So after all of that hard work
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經過努力之後
12:43
where we try to think of all the crazy gases that might be out there,
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我們試想所有有可能出現的瘋狂氣體,
12:46
and we build the very complicated space telescopes
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我們建造非常複雜的太空望遠鏡
12:49
that might be out there,
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或許就在那裡,
12:51
what are we going to find?
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我們將會發現什麼呢?
12:52
Well, in the best case,
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最好的情況是,
12:54
we will find an image of another exo-Earth.
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我們會找到另一張 類地球行星的圖片。
12:58
Here is Earth as a pale blue dot.
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這個淡藍色的點就是地球。
13:00
And this is actually a real photograph of Earth
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這是一張地球的真實照片
13:03
taken by the Voyager 1 spacecraft,
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是由太空船旅行者一號所拍攝的,
13:05
four billion miles away.
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從四十億英里外的距離拍下的。
13:07
And that red light is just scattered light in the camera optics.
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這紅色光線是相機散射的光。
13:11
But what's so awesome to consider
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思考其中的奧妙
13:13
is that if there are intelligent aliens
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如果存在高智慧外星生物
13:16
orbiting on a planet around a star near to us
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靠近我們的行星繞著恆星轉
13:20
and they build complicated space telescopes
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他們建造複雜的太空望遠鏡
13:22
of the kind that we're trying to build,
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我們正在建造的那種望遠鏡,
13:24
all they'll see is this pale blue dot,
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他們看到的也是一個淡藍色點,
13:27
a pinprick of light.
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一個小小的光點。
13:29
And so sometimes, when I pause to think
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有時候,我停下來思考
13:32
about my professional struggle and huge ambition,
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我所面臨的困難和雄心壯志,
13:36
it's hard to think about that
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與浩瀚宇宙相比
13:38
in contrast to the vastness of the universe.
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真是無法比擬。
13:42
But nonetheless, I am devoting the rest of my life
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儘管如此,我打算奉獻我的一生
13:46
to finding another Earth.
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來找尋另一個地球。
13:48
And I can guarantee
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2215
我可以保證
13:50
that in the next generation of space telescopes,
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2383
下一代的太空望遠鏡,
13:52
in the second generation,
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也就是第二代,
13:54
we will have the capability to find and identity other Earths.
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我們有能力找到 並識別其他類地球行星。
13:59
And the capability to split up the starlight
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有能力分開星光的光線
14:02
so that we can look for gases
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找到那些氣體
14:04
and assess the greenhouse gases in the atmosphere,
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確認大氣中溫室氣體的成份,
14:07
estimate the surface temperature,
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預估星球的表面溫度,
14:09
and look for signs of life.
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尋找生命的跡象。
14:11
But there's more.
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不過我們有更多的計劃。
14:13
In this case of searching for other planets like Earth,
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在尋找類地球行星時,
14:16
we are making a new kind of map
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我們也製作一張圖
14:19
of the nearby stars and of the planets orbiting them,
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有關於附近恆星及其行星的太空圖,
14:22
including [planets] that actually might be inhabitable by humans.
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包括可能適合人類居住的行星。
14:26
And so I envision that our descendants,
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我在想我們的後代子孫,
14:29
hundreds of years from now,
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數百年後,
14:31
will embark on an interstellar journey to other worlds.
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透過星際旅行到其他的星球。
14:35
And they will look back at all of us
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他們回顧我們這一代
14:37
as the generation who first found the Earth-like worlds.
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是第一個發現類地星球的一代
14:41
Thank you.
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謝謝各位。
14:42
(Applause)
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(掌聲)
14:49
June Cohen: And I give you, for a question,
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吉恩·科恩:你先提問,
14:51
Rosetta Mission Manager Fred Jansen.
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有請羅塞塔任務管理經理 弗雷德·詹森
14:53
Fred Jansen: You mentioned halfway through
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2031
弗雷德·詹森: 你剛剛有提到
14:55
that the technology to actually look at the spectrum
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那個用來找尋 類地球行星的光譜技術
14:59
of an exoplanet like Earth is not there yet.
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尚未找到。
15:02
When do you expect this will be there,
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你認為何時可實現
15:04
and what's needed?
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我們要如何做?
15:05
Actually, what we expect is what we call our next-generation Hubble telescope.
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事實上, 我們期待下一代哈伯望遠鏡。
15:10
And this is called the James Webb Space Telescope,
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我們稱它為詹姆斯偉伯太空望遠鏡,
15:12
and that will launch in 2018,
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將在 2018 年送上太空,
15:14
and that's what we're going to do,
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這是我們計劃要做的事,
15:16
we're going to look at a special kind of planet
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我們將觀察一種特殊的行星
15:18
called transient exoplanets,
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稱為凌日外行星,
15:20
and that will be our first shot at studying small planets
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那是我們第一次嘗試研究小行星
15:23
for gases that might indicate the planet is habitable.
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以找尋該行星上 存在適合人類居住的氣體。
15:27
JC: I'm going to ask you one follow-up question, too, Sara,
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吉恩:莎拉, 接著我也要問你一個問題,
15:30
as the generalist.
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一個普通的問題。
15:31
So I am really struck by the notion in your career
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在你的職業生涯中
15:34
of the opposition you faced,
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我對你所面臨的問題感到震驚,
15:36
that when you began thinking about exoplanets,
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當你開始思考外行星時,
15:38
there was extreme skepticism in the scientific community
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科學家對於它們是否存在
15:40
that they existed,
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抱著極端懷疑的態度,
15:42
and you proved them wrong.
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你證明他們的想法是錯誤的。
15:43
What did it take to take that on?
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你是如何做到?
15:45
SS: Well, the thing is that as scientists,
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莎拉:身為科學家,
15:47
we're supposed to be skeptical,
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我們理應對事情持有懷疑的態度,
15:49
because our job to make sure that what the other person is saying
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因為我們的工作是 確認他人的觀點
15:52
actually makes sense or not.
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其說法是否合理。
15:53
But being a scientist,
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但是身為科學家,
15:56
I think you've seen it from this session,
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我想你們已從這段演講中看到,
15:58
it's like being an explorer.
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科學家像一個探索者。
16:00
You have this immense curiosity,
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有強烈的好奇心,
16:02
this stubbornness,
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堅決的心,
16:03
this sort of resolute will that you will go forward
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堅定不移的意志 勇往直前
16:06
no matter what other people say.
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無論其他人說了什麼。
16:08
JC: I love that. Thank you, Sara.
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吉恩:說的太好了,謝謝你,莎拉。
16:09
(Applause)
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(掌聲)
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