TED2007
Carolyn Porco: This is Saturn
卡羅琳. 波爾柯：飛向土星
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行星學家卡羅琳.波爾科展示了卡西尼號太空飛船拍攝的土星照片，照片內容主要包括土星最大的衛星--泰坦，以及冰雪覆蓋的土衛二恩克拉多斯。土衛二疑似出現冰泉噴發。
Carolyn Porco - Planetary scientist
As the leader of the Imaging Team on the Cassini mission to Saturn, Carolyn Porco interprets and shares the pictures coming back from this fascinating planet, its rings and its moons. Full bio
As the leader of the Imaging Team on the Cassini mission to Saturn, Carolyn Porco interprets and shares the pictures coming back from this fascinating planet, its rings and its moons. Full bio
Double-click the English transcript below to play the video.
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）
ABOUT THE SPEAKER
Carolyn Porco - Planetary scientistAs the leader of the Imaging Team on the Cassini mission to Saturn, Carolyn Porco interprets and shares the pictures coming back from this fascinating planet, its rings and its moons.
Why you should listen
Planetary scientist Carolyn Porco studies and interprets the photos from NASA space missions like the renowned Voyager mission to the outer solar system in the 1980s and the Cassini-Huygens mission to Saturn. She leads a team of scientists from the US and Europe that has been analyzing the images Cassini has sent back since it left Earth in 1997. At Saturn, they have found new phenomena everywhere they've turned their cameras … in the planet’s atmosphere, within its rings and on the surfaces of its many moons. And they've produced spectacular images and animations of these marvels in the process.
Back in the early-1980s, while still working on her doctorate, Porco was drafted onto the Voyager imaging team to assist in crunching the mountains of data coming back from Voyager’s fly-by of Saturn. Her work on the planet's rings and their relation to its moons cemented her connection with Saturn. After Voyager had flown by Neptune and was nearing conclusion, she worked together with Carl Sagan in planning Voyager’s celebrated Pale Blue Dot picture of Earth.
Her ongoing work at the Cassini Imaging Central Laboratory for Operations (CICLOPs) has two goals: to process, interpret and archive Cassini’s images for other scientists, and to make sure the images -- in all their breathtaking poetry and mystery and sheer Save-Image-As-Desktop awesomeness -- connect with the general public. She is an advocate for the exploration and understanding of planetary space, and her frequent talks (as well as her "Captain's Log" memos on the CICLOPS website) speak to everyone, scientist and nonscientist alike. Her advocacy extends to Hollywood, where she was the character consultant on the 1997 movie “Contact,” and a consultant on the 2009 Paramount Pictures re-boot of “Star Trek.” In 2012, she was named one the 25 most influential people in space by TIME magazine.
Finally, in a twist on the Pale Blue Dot theme, it was she who conceived the idea to invite the people of the world to smile while Cassini imaged the Earth on July 19, 2013 in an event called “The Day the Earth Smiled.”
For more information:
Solar System Portrait: Earth as 'Pale Blue Dot'
BBC: Saturn snapped as Earth smiled
The Atlantic: The Carl Sagan of Our Time Reprises the 'Pale Blue Dot' Photo of Earth
The Day the Earth Smiled: Image
Library of Congress: Portraits of the Solar System: Talking with Carolyn Porco About Carl Sagan
Carolyn Porco | Speaker | TED.com