Carolyn Porco: This is Saturn

55,867 views ・ 2007-10-12

TED


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譯者: Lili Liang 審譯者: Adrienne Lin
00:25
In the next 18 minutes, I'm going to take you on a journey.
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在接下來的18分鐘裡,我將帶大家去旅行。
00:28
And it's a journey that you and I have been on for many years now,
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我們的旅程已經經歷很多年了,
00:33
and it began some 50 years ago, when humans first stepped off our planet.
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50年前,人類第一次涉足外太空時,這段旅程便開始了。
00:39
And in those 50 years, not only did we literally, physically set foot on the moon,
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在這50年裡,我們不僅成功地登上了月球,
00:46
but we have dispatched robotic spacecraft to all the planets -- all eight of them --
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還把太空船發射到了太陽系中的八大行星上
00:53
and we have landed on asteroids, we have rendezvoused with comets,
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我們在隕星上著陸,與彗星相遇,
00:57
and, at this point in time, we have a spacecraft on its way to Pluto,
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現在這一刻,我們有一架太空飛船正向冥王星駛去,
01:02
the body formerly known as a planet.
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飛向這顆曾被認為是行星的星球。
01:05
And all of these robotic missions are part of a bigger human journey:
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所有這些機械裝置的出使任務都是為了將來實現載人航空。
01:11
a voyage to understand something, to get a sense of our cosmic place,
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它們幫助我們了解宇宙,
01:18
to understand something of our origins, and how Earth, our planet,
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了解我們的本源,了解我們的家園地球,
01:23
and we, living on it, came to be.
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過去的狀態,
01:25
And of all the places in the solar system that we might go to
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了解太陽系中所有我們想去的地方,
01:28
and search for answers to questions like this,
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找到所有類似問題的答案。
01:32
there's Saturn. And we have been to Saturn before --
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這是土星。我們曾經到過土星。
01:35
we visited Saturn in the early 1980s --
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1980年代早期我們探訪過土星。
01:38
but our investigations of Saturn have become far more in-depth in detail
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而現在,我們對土星的研究比當時更加深入、仔細。
01:43
since the Cassini spacecraft, traveling across interplanetary space
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卡西尼號太空飛船穿梭於行星之間
01:47
for seven years, glided into orbit around Saturn in the summer of 2004,
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長達七年之久,它2004年駛入土星運行軌道,
01:53
and became at that point the farthest robotic outpost
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成為當時人類發射到太陽系中
01:56
that humanity had ever established around the Sun.
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距離地球最遠的機械裝置。
01:59
Now, the Saturn system is a rich planetary system.
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現在,土星是一個龐大而複雜的行星系統。
02:04
It offers mystery, scientific insight and obviously splendor beyond compare,
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它是如此神祕,充滿了無與倫比的科學研究價值,
02:11
and the investigation of this system has enormous cosmic reach.
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這個系統的勘察,對宇宙學的發展擁有極其深遠的意義。
02:15
In fact, just studying the rings alone, we stand to learn a lot
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實際上,單是從土星的光環中我們就能學到很多
02:19
about the discs of stars and gas that we call the spiral galaxies.
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關於星星可視圓面和旋渦星雲的知識。
02:24
And here's a beautiful picture of the Andromeda Nebula,
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這裡有一張仙女星雲的照片,非常漂亮,
02:26
which is our closest, largest spiral galaxy to the Milky Way.
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這是離銀河系最近,體積最大的旋渦星系。
02:30
And then, here's a beautiful composite of the Whirlpool Galaxy,
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這是渦狀星系,它的構造異常美麗。
02:33
taken by the Hubble Space Telescope.
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這是由哈勃太空望遠鏡所拍攝的。
02:35
So the journey back to Saturn is really part of and is also a metaphor
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飛往土星的這段旅程真是 -- 一個形象的比喻 --
02:41
for a much larger human voyage
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是人類漫長探索之旅的重要部份。
02:43
to understand the interconnectedness of everything around us,
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我們通過探索去了解身邊事物之間的聯繫,
02:47
and also how humans fit into that picture.
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了解人類為何存在。
02:50
And it pains me that I can't tell you all that we have learned with Cassini.
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我很愧疚,在過去的兩年半時間裡,我因為太忙了,
02:57
I can't show you all the beautiful pictures that we've taken
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而沒有向大家展示我們通過卡西尼號探測器收集的信息
03:00
in the last two and a half years, because I simply don't have the time.
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和所有我們拍攝到的無比壯觀的圖片。
03:03
So I'm going to concentrate on two of the most exciting stories
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下面我會講一講這次長達兩年的探索土星之旅,
03:07
that have emerged out of this major exploratory expedition
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我想重點講這次重大探索之旅中
03:11
that we are conducting around Saturn,
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發生的兩件
03:13
and have been for the past two and a half years.
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最令人心潮澎湃的事情。
03:16
Saturn is accompanied by a very large and diverse collection of moons.
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陪伴在土星周圍的是眾多體積龐大,形狀各異的衛星。
03:20
They range in size from a few kilometers across to as big across as the U.S.
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有些衛星的直徑有幾公里,而有些衛星的直徑可以橫跨整個美國。
03:25
Most of the beautiful pictures we've taken of Saturn, in fact,
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我們拍攝到的這些土星美圖基本上
03:28
show Saturn in accompaniment with some of its moons. Here's Saturn with Dione,
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都有土星和圍繞著它的衛星。這是土星和土衛四戴奧妮,
03:33
and then, here's Saturn showing the rings edge-on,
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這是土衛二和土星最外圍的光環,
03:36
showing you just how vertically thin they are, with the moon Enceladus.
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從縱向看,它們有多薄。
03:40
Now, two of the 47 moons that Saturn has are standouts.
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在土星47顆衛星中,有兩顆特別耀眼。
03:45
And those are Titan and Enceladus. Titan is Saturn's largest moon,
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它們分別是土衛六泰坦和土衛二恩克拉多斯。泰坦是土星最大的衛星,
03:50
and, until Cassini had arrived there,
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在卡西尼號到達之前,
03:52
was the largest single expanse of unexplored terrain
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它是我們在太陽系中最大的,
03:56
that we had remaining in our solar system.
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未經勘探的單獨地帶。
04:00
And it is a body that has long intrigued people who've watched the planets.
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它是長期以來研究這些行星的人們朝思暮想的一塊寶地。
04:04
It has a very large, thick atmosphere,
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它的大氣層非常厚,
04:08
and in fact, its surface environment was believed to be
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事實上,它的地表環境被認為是
04:12
more like the environment we have here on the Earth,
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接近於地球上的環境。
04:16
or at least had in the past, than any other body in the solar system.
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至少在過去,人們認為它比其它太陽系中的天體更接近。
04:20
Its atmosphere is largely molecular nitrogen, like you are breathing here in this room,
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它的大氣中含有大量氮分子,就跟你們在這裡吸入的氮氣一樣,
04:25
except that its atmosphere is suffused with
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只不過裡面有過量
04:27
simple organic materials like methane and propane and ethane.
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簡單有機物
04:31
And these molecules high up in the atmosphere of Titan
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這些氣體分子散佈在土衛六大氣的頂層,
04:34
get broken down, and their products join together to make haze particles.
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分解之後,它們的產物化合成霧狀顆粒。
04:39
This haze is ubiquitous. It's completely global and enveloping Titan.
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這些霧狀物四處擴散,把土衛六完全包裹起來。
04:44
And that's why you cannot see down to the surface
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所以單憑我們的肉眼視力,
04:47
with our eyes in the visible region of the spectrum.
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根本無法看清它的表面。
04:49
But these haze particles, it was surmised,
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但是在卡西尼號到達之前,我們推測,這些霧狀顆粒
04:52
before we got there with Cassini, over billions and billions of years,
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經過上千億年的時間
04:56
gently drifted down to the surface and coated the surface
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一點一點積聚並覆蓋在土衛六表面
05:00
in a thick organic sludge.
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形成一層有機的泥狀物。
05:01
So like the equivalent, the Titan equivalent, of tar, or oil, or what -- we didn't know what.
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就像泰坦上的焦油,油,或者類似的甚麼東西 -- 我們當時無法確定。
05:08
But this is what we suspected. And these molecules,
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這是我們的推測。而這些分子,
05:10
especially methane and ethane, can be liquids at the surface temperatures of Titan.
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尤其是甲烷和乙烷,它們在泰坦的地表溫度下會呈現液態。
05:19
And so it turns out that methane is to Titan what water is to the Earth.
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結果發現,甲烷在土衛六上呈現出的狀態,就好跟水在地球上的狀態一樣,
05:24
It's a condensable in the atmosphere,
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它在大氣中是會冷凝的,
05:26
and so recognizing this circumstance brought to the fore
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所以認識到這種情況的存在之後,
05:31
a whole world of bizarre possibilities. You can have methane clouds, OK,
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我們就有了千奇百怪的設想。可能那裡存在甲烷做的雲,是吧,
05:36
and above those clouds, you have this hundreds of kilometers of haze,
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在這些雲之上,幾十萬米厚的霧狀顆粒層
05:39
which prevent any sunlight from getting to the surface.
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遮擋住了陽光,使它無法到達地表。
05:41
The temperature at the surface is some 350 degrees below zero Fahrenheit.
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地表的溫度為華氏零下350度(約攝氏零下212度)。
05:47
But despite that cold, you could have rain falling down on the surface of Titan.
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即使在這樣的低溫下,土衛六上還是會出現降水。
05:53
And doing on Titan what rain does on the Earth: it carves gullies; it forms rivers
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這些降水像地球上的雨水一樣,使地表形成溝渠,河流
05:56
and cataracts; it can create canyons; it can pool in large basins and craters.
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以及瀑布。它還能形成峽谷,大型盆地,以及凹地。
06:03
It can wash the sludge off high mountain peaks and hills,
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它能把泥狀物從高山丘陵上
06:06
down into the lowlands. So stop and think for a minute.
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沖到低窪地帶。我們停下來想一想。
06:09
Try to imagine what the surface of Titan might look like.
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想像土衛六的地表是甚麼樣子的。
06:13
It's dark. High noon on Titan is as dark as deep earth twilight on the Earth.
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那裡一片黑暗 -- 土衛六上的中午時刻跟地球上黎明來臨之前一樣黑暗。
06:18
It's cold, it's eerie, it's misty,
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那裡天寒地凍,陰森恐怖,迷霧重重,
06:20
it might be raining, and you might be standing
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那裡可能正在下雨,而你可能正站在
06:23
on the shores of Lake Michigan brimming with paint thinner. (Laughter)
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氾濫著塗料稀釋劑(成份為甲烷)的密歇根湖邊。
06:27
That is the view that we had of the surface of Titan before we got there with Cassini,
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這是我們在卡西尼號到達土衛六之前的遐想,
06:32
and I can tell you that what we have found on Titan, though it is not the same in detail,
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我可以告訴大家,我們真正在土衛六上發現的,跟我們的想像不盡相同,
06:39
is every bit as fascinating as that story is.
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但是卻一樣引人入勝。
06:42
And for us, it has been like -- the Cassini people --
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對於我們,也就卡西尼號的工作人員而言,
06:44
it has been like a Jules Verne adventure come true.
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這段旅程就像是儒勒·凡爾納(《八十天環遊世界》作者)的小說在現實中上演。
06:48
As I said, it has a thick, extensive atmosphere.
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我剛才說過,它有很厚的一層大氣。
06:50
This is a picture of Titan, backlit by the Sun, with the rings as a beautiful backdrop.
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這張照片是土衛六在被對太陽時被拍下來的,它的光環構成了一幅壯麗的背景。
06:55
And yet another moon there --
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而那裡是另一顆衛星 --
06:57
I don't even know which one it is. It's a very extensive atmosphere.
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我都不知道究竟是哪一顆。這是個擴散得很開的大氣層。
07:00
We have instruments on Cassini which can see down to the surface
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在卡西尼號上有專門儀器能夠幫助我們透過大氣層
07:03
through this atmosphere, and my camera system is one of them.
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看到土衛六地表,我的成像科學子系統就是儀器之一。
07:07
And we have taken pictures like this.
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我們拍下了這些照片。
07:09
And what you see is bright and dark regions, and that's about as far as it got for us.
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你看到的是明於暗的地帶,這是儀器能拍到的最近距離。
07:14
It was so mystifying: we couldn't make out what we were seeing on Titan.
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那裡霧太大了 -- 我們無法確定看到的是甚麼。
07:18
When you look closer at this region, you start to see things
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當你湊近了看那塊區域,你可以看到一些物體,
07:23
like sinuous channels -- we didn't know. You see a few round things.
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形狀像委蛇的溝渠,不知道是甚麼。還可以看到一些圓形圖案。
07:27
This, we later found out, is, in fact, a crater,
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後來我們發現,這原來是一個殞坑,
07:29
but there are very few craters on the surface of Titan,
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但是,土衛六表面的殞坑數量很少,
07:32
meaning it's a very young surface.
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這說明土衛六的地表非常年輕。
07:34
And there are features that look tectonic.
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上面有一些像是由地殻運動產生的地表特徵。
07:36
They look like they've been pulled apart.
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地表像是被外力撕裂了一般。
07:38
Whenever you see anything linear on a planet,
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如果你看到行星表面的一些線形圖案,
07:40
it means there's been a fracture, like a fault.
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那就是地表的裂隙,比如一個斷層。
07:44
And so it's been tectonically altered.
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也就是說土衛六發生過地殻運動。
07:46
But we couldn't make sense of our images,
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但是我們還是無法解讀這些圖像,
07:48
until, six months after we got into orbit,
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直到我們進入軌道六個月之後,
07:52
an event occurred that many have regarded
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一件重大事件發生了。它後來被許多人譽為
07:54
as the highlight of Cassini's investigation of Titan.
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卡西尼號突探測土衛六的突出成就。
07:57
And that was the deployment of the Huygens probe,
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這就是惠更斯號探測器的成功發射。
08:00
the European-built Huygens probe that Cassini had carried
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這個探測器在歐洲被研製出來,乘著卡西尼號
08:03
for seven years across the solar system. We deployed it to the atmosphere of Titan,
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在浩瀚的太陽系里穿梭了七年。我們把它發射到土衛六的大氣中,
08:07
it took two and a half hours to descend, and it landed on the surface.
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兩個半小時之後,它在地表著陸。
08:11
And I just want to emphasize how significant an event this is.
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我真想強調一下這一行動的重大意義。
08:15
This is a device of human making,
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這是人類歷史上第一次有人造的機器
08:18
and it landed in the outer solar system for the first time in human history.
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在外太陽系的天體上登陸。
08:22
It is so significant that, in my mind,
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在我心目中,它實在是意義非凡,
08:26
this was an event that should have been celebrated
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我們值得為它
08:28
with ticker tape parades in every city across the U.S. and Europe,
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在美國,歐洲的大街小巷敲鑼打鼓,舉行盛大遊行,
08:33
and sadly, that wasn't the case.
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真遺憾,這沒有得到響應。
08:35
(Laughter).
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(眾人笑)
08:37
It was significant for another reason. This is an international mission,
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另一個顯示其重大意義的理由是,這是一項國際合作項目,
08:40
and this event was celebrated in Europe, in Germany,
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在德國,人們為此事舉行了歡慶活動,
08:43
and the celebratory presentations were given in English accents,
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慶典節目的表演者有英國人,
08:47
and American accents, and German accents, and French and Italian and Dutch accents.
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美國人,德國人,法國人,義大利人,和荷蘭人。
08:53
It was a moving demonstration of what the words
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這是在用行動來詮釋
08:57
"united nations" are supposed to mean:
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“聯合國”一詞的真諦:
08:59
a true union of nations joined together in a colossal effort for good.
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國家之間真誠團結協作,眾志成城。
09:05
And, in this case, it was a massive undertaking to explore a planet,
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探測一顆遙不可及的星球
09:09
and to come to understand a planetary system
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並試圖了解一個星球的體系
09:12
that, for all of human history, had been unreachable,
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需要耗費龐大的人力物力。
09:16
and now humans had actually touched it.
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而現在,人類終於到達了這樣一個星球。
09:18
So it was -- I mean, I'm getting goose bumps just talking about it.
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這真是 -- 我只是說一下,就開始起雞皮疙瘩了,
09:22
It was a tremendously emotional event,
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這的確是激動人心的一件事,
09:24
and it's something that I will personally never forget, and you shouldn't either.
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它讓我永生難忘,你們也應該有同感。
09:29
(Applause).
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(眾人鼓掌)
09:35
But anyway, the probe took measurements of the atmosphere on the way down,
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探測器在降落過程中對大氣進行了測量,
09:38
and it also took panoramic pictures.
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並且拍攝了全景照片。
09:40
And I can't tell you what it was like to see the first pictures
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我無法用言語來表達第一次看到土衛六地表照片時
09:44
of Titan's surface from the probe. And this is what we saw.
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我的心情有多麼激動。這是我們看到的景象。
09:48
And it was a shocker, because it was everything we wanted
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太令人震驚了,這些從土星軌道上拍攝的景象
09:51
those other pictures taken from orbit to be.
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和我們的設想正好吻合。
09:53
It was an unambiguous pattern, a geological pattern.
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地表呈現出清晰的幾何圖案。
09:57
It's a dendritic drainage pattern that can be formed only by the flow of liquids.
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它所呈現出的樹枝狀水流圖案,肯定是因液體的流動而形成的。
10:02
And you can follow these channels
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你可以沿著這些溝渠
10:04
and you can see how they all converge.
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找到它們的匯合點。
10:05
And they converge into this channel here, which drains into this region.
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它們匯聚到這條溝里,從這裡滲透到地下。
10:09
You are looking at a shoreline.
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你們看到的是一條海岸線。
10:11
Was this a shoreline of fluids? We didn't know.
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這是液體的海岸線嗎?我們不知道。
10:14
But this is somewhat of a shoreline.
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但是,這肯定是一條海岸線。
10:16
This picture is taken at 16 kilometers.
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這是在離地表16公里的高度所拍攝的照片。
10:18
This is the picture taken at eight kilometers, OK? Again, the shoreline.
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這張是在8公里的高度拍攝的。看,還是那條海岸線。
10:22
Okay, now, 16 kilometers, eight kilometers -- this is roughly an airline altitude.
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好,16公里,8公里 -- 大概就是普通飛機的飛行高度。
10:27
If you were going to take an airplane trip across the U.S.,
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如果你乘飛機橫跨美國,
10:30
you would be flying at these altitudes.
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這就相當於你的飛行高度。
10:32
So, this is the picture you would have at the window of Titanian Airlines
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假如你正乘坐著土衛六航空公司的飛機俯瞰土衛六,
10:36
as you fly across the surface of Titan. (Laughter)
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你看到的就是這副景象。(眾人笑)
10:39
And then finally, the probe came to rest on the surface,
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最後,探測器在地面著陸。
10:43
and I'm going to show you, ladies and gentlemen,
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女士們,先生們,下面我為你們展示
10:45
the first picture ever taken from the surface of a moon in the outer solar system.
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首張外太陽系衛星表面的照片。
10:49
And here is the horizon, OK?
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這裡是地平線,看見了嗎?
10:53
These are probably water ice pebbles, yes?
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這些很可能是冰鵝卵石。
10:57
(Applause).
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(眾人鼓掌)
11:02
And obviously, it landed in one of these flat, dark regions
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很明顯,它落在了其中一塊平坦的陰影地帶。
11:06
and it didn't sink out of sight. So it wasn't fluid that we landed in.
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它沒有沉沒消失,這說明它沒有落在液體上。
11:11
What the probe came down in was basically
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實際上,它降落的地點
11:14
the Titan equivalent of a mud flat.
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類似於一灘淤泥。
11:17
This is an unconsolidated ground that is suffused with liquid methane.
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這是液態甲烷形成的半流體。
11:22
And it's probably the case that this material
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形成這種地貌的原因可能是
11:25
has washed off the highlands of Titan
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液態甲烷順著我們剛才看到的那些溝渠
11:29
through these channels that we saw,
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沖蝕了土衛六上的高地,
11:30
and has drained over billions of years to fill in low-lying basins.
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滲透並填充到低窪地帶長達幾十億年的時間。
11:34
And that is what the Huygens probe landed in.
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這就是惠更斯號探測器著陸的地方。
11:37
But still, there was no sign in our images,
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然而,我們還是沒有看到我們之前預想的
11:41
or even in the Huygens' images, of any large, open bodies of fluids.
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或者惠更斯號圖片上顯示的大面積液體。
11:46
Where were they? It got even more puzzling when we found dunes.
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都在哪裡呢?當我們看到一些沙丘時,我們就更加困惑了。
11:51
OK, so this is our movie of the equatorial region of Titan,
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這里是土衛六赤道地帶的錄像,
11:54
showing these dunes. These are dunes that are 100 meters tall,
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這些就是上面的沙丘。它們高達100米,
11:57
separated by a few kilometers,
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之間相隔幾公里遠,
12:00
and they go on for miles and miles and miles.
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延綿數千英里。
12:03
There's hundreds, up to a 1,000 or 1,200 miles of dunes.
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這些沙丘帶短則幾百英里,長則1000到1200英里。
12:06
This is the Saharan desert of Titan.
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這簡直就相當於土衛六的撒哈拉沙漠。
12:09
It's obviously a place which is very dry, or you wouldn't get dunes.
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顯然,這裡非常乾燥,否則不會有沙丘。
12:14
So again, it got puzzling that there were no bodies of fluid,
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這讓人更加懷疑這裡是否有液態物存在,
12:19
until finally, we saw lakes in the polar regions.
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直到我們最後看到了極地的湖泊。
12:23
And there is a lake scene in the south polar region of Titan.
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這是土衛六南極的一個湖。
12:27
It's about the size of Lake Ontario.
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它的大小相當於安大略湖。
12:29
And then, only a week and a half ago,
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接著,也就一個多星期以後,
12:30
we flew over the north pole of Titan and found, again,
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我們飛過北極,
12:34
we found a feature here the size of the Caspian Sea.
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發現了相當於加勒比海大小的一片區域。
12:39
So it seems that the liquids, for some reason we don't understand,
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不知為何,可能是這個季節的原因,土衛六上的液體,
12:43
or during at least this season, are apparently at the poles of Titan.
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都出現在極地地帶。
12:48
And I think you would agree that we have found Titan
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相信你們應該會同意,土衛六是一個
12:51
is a remarkable, mystical place. It's exotic, it's alien, but yet strangely Earth-like,
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不可思議的地方。它是那麼特別,那麼遙遠,但又和地球有著驚人的相似處。
12:58
and having Earth-like geological formations
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它有著像類似地球表面的地貌
13:01
and a tremendous geographical diversity,
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和豐富的地質多樣性。
13:05
and is a fascinating world whose only rival in the solar system
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它是個複雜而豐富多彩的世界,是太陽系中
13:09
for complexity and richness is the Earth itself.
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唯一能和地球相媲美的天體。
13:12
And so now we go onto Enceladus. Enceladus is a small moon,
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我們現在飛到土衛二看看。它是一個小型衛星,
13:17
it's about a tenth the size of Titan. And you can see it here next to England,
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大小僅有土衛六的十分之一,可以和圖中旁邊的英國比較一下。
13:21
just to show you the size. This is not meant to be a threat.
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我只是讓你們看看它的大小;沒有威脅英國的意思。
13:24
(Laughter).
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(眾人笑)
13:26
And Enceladus is very white, it's very bright,
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土衛二很白很亮,
13:30
and its surface is obviously wrecked with fractures.
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它的表面有很明顯的裂痕,
13:34
It is a very geologically active body.
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它的地殻運動很頻繁。
13:36
But the mother lode of discoveries on Enceladus
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但是我們在土衛二上的發現
13:38
was found at the south pole -- and we're looking at the south pole here --
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大多集中在它的南極地帶 -- 我們現在看到的就是南極 --
13:41
where we found this system of fractures.
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在這裡,我們發現了一系列地裂。
13:44
And they're a different color because they're a different composition.
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它們的顏色各有不同,這是因為它們的成份不同。
13:46
They are coated. These fractures are coated with organic materials.
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它們的表面覆蓋著不同的有機物質。
13:51
Moreover, this whole, entire region, the south polar region,
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這整個南極地帶
13:55
has elevated temperatures. It's the hottest place on the planet, on the body.
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越往高處氣溫越高。這裡是整個星球溫度最高的地方。
13:59
That's as bizarre as finding that the Antarctic on the Earth is hotter than the tropics.
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這現象非常奇特,想像地球南極洲比熱帶地區還熱會是甚麼情況。
14:04
And then, when we took additional pictures, we discovered
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接著,我們拍攝了更多照片,
14:07
that from these fractures are issuing jets of fine, icy particles
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我們發現從這些地裂中,有細小的冰粒噴射出來,
14:13
extending hundreds of miles into space.
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噴射範圍為方圓幾百英里。
14:15
And when we color-code this image, to bring out the faint light levels,
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我們對此作了光譜分析,
14:18
we see that these jets feed a plume
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我們看到這些冰泉在土衛二的上空
14:22
that, in fact, we see, in other images, goes thousands of miles
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呈現羽狀噴射,
14:26
into the space above Enceladus.
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噴射高度達到幾千英里。
14:28
My team and I have examined images like this,
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我們的團隊對這些圖片進行了分析,
14:31
and like this one, and have thought about the other results from Cassini.
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這是其中一張,另外思考過卡西尼號的其它發現。
14:35
And we have arrived at the conclusion
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我們做出這樣的結論,
14:39
that these jets may be erupting from pockets
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這些噴射現象是由土衛二
14:42
of liquid water under the surface of Enceladus.
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地表下的液態水,從冰缺口噴發而出所造成的。
14:46
So we have, possibly, liquid water, organic materials and excess heat.
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那裡可能存在液態水,有機物質和過剩的熱量。
14:51
In other words, we have possibly stumbled upon
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換句話說,我們很有可能湊巧
14:54
the holy grail of modern day planetary exploration,
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發現了現代行星探索的新大陸。
14:58
or in other words, an environment that is potentially suitable for living organisms.
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也就是說,我們找到了一片可能適合有機生命生長的環境。
15:02
And I don't think I need to tell you that the discovery of life
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就算我不說,大家也知道,如果在太陽系其它地方
15:05
elsewhere in our solar system,
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找到生命,
15:07
whether it be on Enceladus or elsewhere,
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不管是在土衛二或其它甚麼地方,
15:09
would have enormous cultural and scientific implications.
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對於在科學和文化領域,這都是巨大而深遠的衝擊。
15:12
Because if we could demonstrate that genesis had occurred
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假如我們能夠證明《創世紀》中的神跡
15:16
not once, but twice, independently, in our solar system,
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能夠在我們的太陽系中分別發生兩次,而不僅僅是一次,
15:20
then that means, by inference, it has occurred a staggering number of times
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那麼,照此推斷,它在茫茫宇宙137億年的歷史中,
15:24
throughout the universe and its 13.7 billion year history.
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肯定已經發生過無數次了。
15:29
Right now, Earth is the only planet still that we know is teeming with life.
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目前,地球仍是唯一一顆有生命存在的星球。
15:33
It is precious, it is unique,
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它是那麼珍貴,獨一無二。
15:36
it is still, so far, the only home we've ever known.
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它依然是我們唯一的家園。
15:39
And if any of you were alert and coherent during the 1960s --
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如果在座的哪位1960年代的時候頭腦還靈活 --
15:46
and we'd forgive you, if you weren't, OK --
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不靈活也沒關係,
15:48
you would remember this very famous picture
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你可能會認得1968年
15:50
taken by the Apollo 8 astronauts in 1968.
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由阿波羅八號太空人拍下的這張著名照片。
15:54
It was the first time that Earth was imaged from space,
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這是第一張從太空拍攝的地球照片。
15:57
and it had an enormous impact on our sense of place in the universe,
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它極大地衝擊了我們對宇宙認識,
16:00
and our sense of responsibility for the protection of our own planet.
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影響了我們保護地球的責任感。
16:05
Well, we on Cassini have taken an equivalent first,
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我們的卡西尼號同樣拍下了一張
16:09
a picture that no human eye has ever seen before.
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此前人們從未見過的照片。
16:13
It is a total eclipse of the Sun, seen from the other side of Saturn.
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它是在日全蝕的時候,從土星的另一側拍攝的。
16:17
And in this impossibly beautiful picture,
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在這張無與倫比的照片上
16:21
you see the main rings backlit by the Sun,
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你們可以看見背著陽光的土星主光環,
16:23
you see the refracted image of the Sun
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看到太陽折射後的形象,
16:26
and you see this ring created, in fact,
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還可以看到由土衛二表面羽狀物
16:28
by the exhalations of Enceladus.
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形成的光暈。
16:31
But as if that weren't brilliant enough, we can spot, in this beautiful image,
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如果這些都還不夠引人入勝的話,我們還能在這美麗畫卷上
16:37
sight of our own planet,
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找到我們的地球,
16:39
cradled in the arms of Saturn's rings.
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它正依偎在土星光環的臂彎中。
16:43
Now, there is something deeply moving
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當我們從另一片天地
16:45
about seeing ourselves from afar,
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遙望我們自己,
16:47
and capturing the sight of our little, blue-ocean planet
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窺見到那眇小的,海藍色的地球
16:50
in the skies of other worlds.
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我們不能不為之動容。
16:52
And that, and the perspective of ourselves that we gain from that,
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也許,我們得到這個觀察的視角
16:56
may be, in the end, the finest reward that we earn
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就是我們在這次長達半個世紀的旅程中
17:00
from this journey of discovery that started half a century ago.
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最有價值的奬勵。
17:03
And thank you very much.
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非常感謝大家。
17:05
(Applause)
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(熱烈鼓掌)

Original video on YouTube.com
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