Carolyn Porco: This is Saturn

翻译人员: Wang Qian 校对人员: Zachary Lin Zhao

In the next 18 minutes, I'm going to take you on a journey.

在接下来的18分钟里，我会带大家

And it's a journey that you and I have been on for many years now,

踏上一个你我都没停下脚步的旅程，

and it began some 50 years ago, when humans first stepped off our planet.

50多年前，人类首度迈出地球。

And in those 50 years, not only did we literally, physically set foot on the moon,

在这50年间，人类不仅迈向月球，

but we have dispatched robotic spacecraft to all the planets -- all eight of them --

还向所有8个行星发送机器人，

and we have landed on asteroids, we have rendezvoused with comets,

我们的足迹遍布小行星，我们还同彗星有亲密接触，

and, at this point in time, we have a spacecraft on its way to Pluto,

现在，我们正有一个飞船驶向冥王星，

the body formerly known as a planet.

过去冥王星也被认作行星之一。

And all of these robotic missions are part of a bigger human journey:

所有这些机器人探测计划都是人类征程的一部分：

a voyage to understand something, to get a sense of our cosmic place,

一个为理解而出发的征程，为理解我们置身的宇宙，

to understand something of our origins, and how Earth, our planet,

为理解人类的起源，为理解地球、

and we, living on it, came to be.

和人类的发展。

And of all the places in the solar system that we might go to

在太阳系中我们足迹可以遍及的各个角落

and search for answers to questions like this,

我们寻找答案，

there's Saturn. And we have been to Saturn before --

人类曾登上过土星--

we visited Saturn in the early 1980s --

早在上世纪80年代初--

but our investigations of Saturn have become far more in-depth in detail

人类对土星的探索变得更加深入、透彻

since the Cassini spacecraft, traveling across interplanetary space

自打7年前罗西尼号探测器遨游在星际间

for seven years, glided into orbit around Saturn in the summer of 2004,

2004年罗西尼正式进入土星轨道，

and became at that point the farthest robotic outpost

成为当时

that humanity had ever established around the Sun.

人类在太阳系走的最远的探测器。

Now, the Saturn system is a rich planetary system.

现在，土星是一个丰饶的行星系统。

It offers mystery, scientific insight and obviously splendor beyond compare,

她的神秘感、她带给科学的新视角及她无与伦比的光环

and the investigation of this system has enormous cosmic reach.

带给宇宙探索无限的新发现。

In fact, just studying the rings alone, we stand to learn a lot

光是研究她的光环，我们就学到很多

about the discs of stars and gas that we call the spiral galaxies.

我们把那些星星的环状聚集体称为螺旋星系

And here's a beautiful picture of the Andromeda Nebula,

这张令人惊艳的照片是仙女座星系

which is our closest, largest spiral galaxy to the Milky Way.

仙女座星系距地球最近，同时也是银河中最大的螺旋星系

And then, here's a beautiful composite of the Whirlpool Galaxy,

这是哈伯太空望远镜拍摄的漩涡星系

taken by the Hubble Space Telescope.

一张美丽的图片

So the journey back to Saturn is really part of and is also a metaphor

所以去土星的旅程实际上是--打个比方

for a much larger human voyage

人类征程的放大

to understand the interconnectedness of everything around us,

要了解与周围万物的内在关联性

and also how humans fit into that picture.

以及人类在其中的作用

And it pains me that I can't tell you all that we have learned with Cassini.

不能向大家展示所有卡西尼传回的信息，我很难受

I can't show you all the beautiful pictures that we've taken

因为时间缘故

in the last two and a half years, because I simply don't have the time.

我无法向大家展示过去两年半拍摄的美丽照片

So I'm going to concentrate on two of the most exciting stories

不过，我会着重于

that have emerged out of this major exploratory expedition

过去两年半

that we are conducting around Saturn,

探索土星旅程中

and have been for the past two and a half years.

两个最激动人心的方面

Saturn is accompanied by a very large and diverse collection of moons.

土星被一组庞大而多样的卫星所环绕

They range in size from a few kilometers across to as big across as the U.S.

它们当中，有的仅几千米大，有的有美国从东南到北那么大

Most of the beautiful pictures we've taken of Saturn, in fact,

其实，最美丽的照片

show Saturn in accompaniment with some of its moons. Here's Saturn with Dione,

是那些有卫星环绕的土星照片。这是一张土星和土卫四

and then, here's Saturn showing the rings edge-on,

这是一张土星光环侧向地球

showing you just how vertically thin they are, with the moon Enceladus.

这光环实际上纵向是很浅薄的，旁边是土卫二

Now, two of the 47 moons that Saturn has are standouts.

土星47个卫星中有两个是很突出的

And those are Titan and Enceladus. Titan is Saturn's largest moon,

土卫六和土卫二。土卫六是土星最大的卫星

and, until Cassini had arrived there,

直到卡西尼进入其轨道

was the largest single expanse of unexplored terrain

这是对太阳系未知领域的

that we had remaining in our solar system.

又一次重大探索

And it is a body that has long intrigued people who've watched the planets.

对于研究行星的人这可是一个令人朝思暮想的形体

It has a very large, thick atmosphere,

它有一个巨大、浑厚的大气

and in fact, its surface environment was believed to be

事实上它的气候

more like the environment we have here on the Earth,

与地球大气非常接近

or at least had in the past, than any other body in the solar system.

至少过去相较于其他行星来说是这样的

Its atmosphere is largely molecular nitrogen, like you are breathing here in this room,

它的大气有分子态氮组成，就像我们现在这个房间一样

except that its atmosphere is suffused with

不过它的大气中充满

simple organic materials like methane and propane and ethane.

甲烷、丙烷和乙烷等有机材质

And these molecules high up in the atmosphere of Titan

土卫六上这些分子含量很高

get broken down, and their products join together to make haze particles.

这些分子分解后形成烟雾

This haze is ubiquitous. It's completely global and enveloping Titan.

这些烟雾无处不在，弥漫于整个土卫六

And that's why you cannot see down to the surface

在我们肉眼可辨识的范围内

with our eyes in the visible region of the spectrum.

其表面是不可见的

But these haze particles, it was surmised,

但这些雾气的存在不过是推测

before we got there with Cassini, over billions and billions of years,

在卡西尼探测的数亿年前

gently drifted down to the surface and coated the surface

这些雾气悬浮于地表后附着其上

in a thick organic sludge.

形成有机污垢

So like the equivalent, the Titan equivalent, of tar, or oil, or what -- we didn't know what.

类似于地球上的焦油，或油什么的，我也不清楚

But this is what we suspected. And these molecules,

我们是这样推测的。这些分子

especially methane and ethane, can be liquids at the surface temperatures of Titan.

尤其是甲烷和乙烷，在土星地温下是液态的。

And so it turns out that methane is to Titan what water is to the Earth.

我们发现甲烷就是土星的水。

It's a condensable in the atmosphere,

在大气里是可以凝缩的

and so recognizing this circumstance brought to the fore

这一发现

a whole world of bizarre possibilities. You can have methane clouds, OK,

为许多稀奇古怪的设想提供了可能。土星有甲烷云层。

and above those clouds, you have this hundreds of kilometers of haze,

甲烷云层上有数百公里高的雾气层

which prevent any sunlight from getting to the surface.

光线无法穿透云层射向地面

The temperature at the surface is some 350 degrees below zero Fahrenheit.

土星地面气温仅为零下350华氏度

But despite that cold, you could have rain falling down on the surface of Titan.

虽冷，但还有雨

And doing on Titan what rain does on the Earth: it carves gullies; it forms rivers

就像地球一样，土星在雨的作用下形成溪谷河流

and cataracts; it can create canyons; it can pool in large basins and craters.

和大瀑布、峡谷、盆地和地坑。

It can wash the sludge off high mountain peaks and hills,

雨洗净山顶的污垢

down into the lowlands. So stop and think for a minute.

然后冲向地底。大家停下来想一想

Try to imagine what the surface of Titan might look like.

土星的地表会是什么样子呢？

It's dark. High noon on Titan is as dark as deep earth twilight on the Earth.

月光下的土星是黑暗的，就像黎明前的地球

It's cold, it's eerie, it's misty,

此时寒冷、阴森、雾气缭绕

it might be raining, and you might be standing

还有可能在下雨，想象站在雨中

on the shores of Lake Michigan brimming with paint thinner. (Laughter)

面前是密歇根湖，闪闪发光

That is the view that we had of the surface of Titan before we got there with Cassini,

在卡西尼问世前，我们是这样想象土星的

and I can tell you that what we have found on Titan, though it is not the same in detail,

我们的发现，虽细节上有差异

is every bit as fascinating as that story is.

但同样令人神往

And for us, it has been like -- the Cassini people --

对于我们来说，对热爱卡西尼的人来所

it has been like a Jules Verne adventure come true.

这就像凡尔纳的小说变成现实

As I said, it has a thick, extensive atmosphere.

正如我所说的，土星有一个厚重的大气

This is a picture of Titan, backlit by the Sun, with the rings as a beautiful backdrop.

这张是土星在太阳的光辉下光环奕奕生彩的照片

And yet another moon there --

这是另一个卫星

I don't even know which one it is. It's a very extensive atmosphere.

我也不清楚是哪一个。它的大气面积很大

We have instruments on Cassini which can see down to the surface

卡西尼上的设备可以穿过大气看清土星地表

through this atmosphere, and my camera system is one of them.

我的设备也在上面

And we have taken pictures like this.

我们的照片中有这样的

And what you see is bright and dark regions, and that's about as far as it got for us.

其中有光明和黑暗的区域，我们的设备也只能达到这个水平

It was so mystifying: we couldn't make out what we were seeing on Titan.

这很神秘--我们怎样也无法弄清土星地表

When you look closer at this region, you start to see things

仔细观察你会有所发现

like sinuous channels -- we didn't know. You see a few round things.

比如蜿蜒的渠道，这是我们以前所不知的，你还能看到环状物

This, we later found out, is, in fact, a crater,

后来我们这是一个地坑

but there are very few craters on the surface of Titan,

但土卫六上却没有几个

meaning it's a very young surface.

所以这个地表是新形成的

And there are features that look tectonic.

同时还有地质构造

They look like they've been pulled apart.

有些似乎是被撕裂的

Whenever you see anything linear on a planet,

在任何行星上看到线形地质

it means there's been a fracture, like a fault.

就说明有断层

And so it's been tectonically altered.

这里的地质结构被改变过

But we couldn't make sense of our images,

但我们无法理解这些图片

until, six months after we got into orbit,

直到6个月后卡西尼进入土星轨道

an event occurred that many have regarded

一个发现可以被称为

as the highlight of Cassini's investigation of Titan.

卡西尼土星征程的里程碑

And that was the deployment of the Huygens probe,

这是惠更斯号探测器的投入使用

the European-built Huygens probe that Cassini had carried

卡西尼携带的欧洲制造的惠更斯号

for seven years across the solar system. We deployed it to the atmosphere of Titan,

傲游了7年。我们将它步入土卫六大气中

it took two and a half hours to descend, and it landed on the surface.

经过两个半小时的降落，最终着陆与土卫六

And I just want to emphasize how significant an event this is.

我想强调一下其重要性

This is a device of human making,

这是人造的设备

and it landed in the outer solar system for the first time in human history.

在人类历史上首次着陆与太阳系外

It is so significant that, in my mind,

这对我很重要

this was an event that should have been celebrated

我们应该在欧美用彩车

with ticker tape parades in every city across the U.S. and Europe,

大肆庆祝

and sadly, that wasn't the case.

虽没实现

(Laughter).

（笑）

It was significant for another reason. This is an international mission,

重大的原因还有一个，那就是，这是一次国际任务

and this event was celebrated in Europe, in Germany,

在欧洲，德国，人们举国欢庆

and the celebratory presentations were given in English accents,

庆祝演讲在英国

and American accents, and German accents, and French and Italian and Dutch accents.

美国、德国、法国、意大利和荷兰进行

It was a moving demonstration of what the words

这是你个激动人心的对

"united nations" are supposed to mean:

“联合国”的定义

a true union of nations joined together in a colossal effort for good.

一个真正的各个国家参与的，致力于人类共同未来的联合体

And, in this case, it was a massive undertaking to explore a planet,

这样，探索一颗行星是一个极大的任务

and to come to understand a planetary system

并且，实现探索了一个人类历史上不曾踏足的

that, for all of human history, had been unreachable,

行星系统

and now humans had actually touched it.

是多么一个壮举

So it was -- I mean, I'm getting goose bumps just talking about it.

一说的这儿，我都起鸡皮疙瘩了

It was a tremendously emotional event,

这是几个激动人心的时刻

and it's something that I will personally never forget, and you shouldn't either.

我会永远铭记，大家也应铭记在心

(Applause).

（鼓掌）

But anyway, the probe took measurements of the atmosphere on the way down,

但是，探测器在着陆过程中收集了数据

and it also took panoramic pictures.

拍摄了全景照片

And I can't tell you what it was like to see the first pictures

那第一张土卫六地表的照片真的是无法形容的

of Titan's surface from the probe. And this is what we saw.

它是这样的

And it was a shocker, because it was everything we wanted

挺让人震惊的，这就是我们期待已久的

those other pictures taken from orbit to be.

轨道上的照片

It was an unambiguous pattern, a geological pattern.

这是一个清晰的、地理的图像

It's a dendritic drainage pattern that can be formed only by the flow of liquids.

这种树枝状的格局只会是水流形成的

And you can follow these channels

你可以在水道中航行

and you can see how they all converge.

看看他们是如何覆盖地表的

And they converge into this channel here, which drains into this region.

水道进入这个流域后又注入那个地区

You are looking at a shoreline.

你看到的是滨线

Was this a shoreline of fluids? We didn't know.

是液态的吗？我们不得而知

But this is somewhat of a shoreline.

但这是某种形态的滨线

This picture is taken at 16 kilometers.

这张照片是在16千米的高空拍摄的

This is the picture taken at eight kilometers, OK? Again, the shoreline.

这张是8千米。好，再看滨线

Okay, now, 16 kilometers, eight kilometers -- this is roughly an airline altitude.

好，16千米，8千米--

If you were going to take an airplane trip across the U.S.,

这大约就是在美国的

you would be flying at these altitudes.

飞机飞行高度

So, this is the picture you would have at the window of Titanian Airlines

这就是飞行在土卫六上的飞机

as you fly across the surface of Titan. (Laughter)

窗外的景色（笑）

And then finally, the probe came to rest on the surface,

最后，探测器着陆

and I'm going to show you, ladies and gentlemen,

女士们、先生们，我将向你们展示

the first picture ever taken from the surface of a moon in the outer solar system.

首张太阳系外行星卫星地表照片

And here is the horizon, OK?

这是地平线

These are probably water ice pebbles, yes?

这些是小冰块

(Applause).

（鼓掌）

And obviously, it landed in one of these flat, dark regions

很明显，探测器着陆与平坦、黑暗的区域

and it didn't sink out of sight. So it wasn't fluid that we landed in.

探测器没有下沉消失。所以它没有落在水路上

What the probe came down in was basically

实际上这是

the Titan equivalent of a mud flat.

土卫六版的泥巴地

This is an unconsolidated ground that is suffused with liquid methane.

这片疏松的土地上充满了液态的甲烷

And it's probably the case that this material

大概这就是为何这些物质

has washed off the highlands of Titan

冲下土卫六的高地

through these channels that we saw,

流下那些我们看过的水道

and has drained over billions of years to fill in low-lying basins.

万年不变的注入低洼的盆地

And that is what the Huygens probe landed in.

惠更斯号就着陆于此

But still, there was no sign in our images,

但我们的照片中

or even in the Huygens' images, of any large, open bodies of fluids.

惠更斯号传回的照片中还是没有一点水的迹象

Where were they? It got even more puzzling when we found dunes.

水在哪儿呢？当我们发现沙丘的时候，这一切变得更加扑朔迷离。

OK, so this is our movie of the equatorial region of Titan,

这是我们土卫六赤道区域的影象

showing these dunes. These are dunes that are 100 meters tall,

这些视频中的沙丘都有100多米高

separated by a few kilometers,

每个相间几千米

and they go on for miles and miles and miles.

它们延绵不绝

There's hundreds, up to a 1,000 or 1,200 miles of dunes.

这是1000到1200公里长的沙丘

This is the Saharan desert of Titan.

可以称得上是土卫六的撒哈拉

It's obviously a place which is very dry, or you wouldn't get dunes.

很明显，要是不干燥就不会有沙丘

So again, it got puzzling that there were no bodies of fluid,

所以，让人费解的是没有水

until finally, we saw lakes in the polar regions.

但后来我们在两极地区找到湖泊

And there is a lake scene in the south polar region of Titan.

这是一张土卫六南极湖区的景致

It's about the size of Lake Ontario.

大概有安大略湖那么大

And then, only a week and a half ago,

就在10天前

we flew over the north pole of Titan and found, again,

探测器在土卫六北极上空飞行时

we found a feature here the size of the Caspian Sea.

找到有里海那么大的图像

So it seems that the liquids, for some reason we don't understand,

我们不解的是，那液体

or during at least this season, are apparently at the poles of Titan.

在某些季节会出现在土卫六极地地区

And I think you would agree that we have found Titan

你也会觉得土卫六

is a remarkable, mystical place. It's exotic, it's alien, but yet strangely Earth-like,

很奇妙、神秘。充满异域风情。但有处处与地球相似

and having Earth-like geological formations

有地球一样的地貌

and a tremendous geographical diversity,

以及繁多的地形

and is a fascinating world whose only rival in the solar system

这个神奇的行星在太阳系里

for complexity and richness is the Earth itself.

唯一可以与之在复杂性和丰富性上相抗衡的只有地球

And so now we go onto Enceladus. Enceladus is a small moon,

再来看看土卫二。土卫二是个很小的星球

it's about a tenth the size of Titan. And you can see it here next to England,

大有只有土卫六十分之一大，这是它和英国做比较

just to show you the size. This is not meant to be a threat.

只是比较大小，不是地球安全威胁

(Laughter).

（笑）

And Enceladus is very white, it's very bright,

土卫二很白，很亮

and its surface is obviously wrecked with fractures.

其地表充满断裂层

It is a very geologically active body.

土卫二地质活动活跃

But the mother lode of discoveries on Enceladus

但其南极上的母矿

was found at the south pole -- and we're looking at the south pole here --

--这是南极

where we found this system of fractures.

我们在此发现地质断裂

And they're a different color because they're a different composition.

这块儿颜色不一样是因为组成不同

They are coated. These fractures are coated with organic materials.

这些断层上附着这有机物质

Moreover, this whole, entire region, the south polar region,

同时，着整个区域，南极区域

has elevated temperatures. It's the hottest place on the planet, on the body.

温度升高。是土卫二上温度最高的地区

That's as bizarre as finding that the Antarctic on the Earth is hotter than the tropics.

这很怪，就像哪天地球上的南极变得比赤道地区还热

And then, when we took additional pictures, we discovered

再看看其他照片

that from these fractures are issuing jets of fine, icy particles

从这些断层中喷射出冰物质

extending hundreds of miles into space.

喷向空中

And when we color-code this image, to bring out the faint light levels,

经过图像处理呈现出的光线渐变

we see that these jets feed a plume

我们可以看到喷射出的冰状物形成羽毛形状

that, in fact, we see, in other images, goes thousands of miles

在其它图像中，有上千里

into the space above Enceladus.

直入土卫二的空中

My team and I have examined images like this,

我和我的小组对图像进行分析

and like this one, and have thought about the other results from Cassini.

就像这张，还有其他卡西尼传回的照片

And we have arrived at the conclusion

我们得出结论

that these jets may be erupting from pockets

这些喷出物可能是从小区域喷出的

of liquid water under the surface of Enceladus.

土卫二地下的液体

So we have, possibly, liquid water, organic materials and excess heat.

可能是液体，有机物或余热

In other words, we have possibly stumbled upon

这是意外的发现

the holy grail of modern day planetary exploration,

现代星系探索的圣杯

or in other words, an environment that is potentially suitable for living organisms.

也就是另一个生命体可以存活的环境

And I don't think I need to tell you that the discovery of life

不用我说，大家都知道在太阳系内其他行星

elsewhere in our solar system,

不管是土卫二还是其他什么地方

whether it be on Enceladus or elsewhere,

发现生命迹象

would have enormous cultural and scientific implications.

在文化和科技上是多么重大的啊

Because if we could demonstrate that genesis had occurred

要是我们可以证明创世纪的存在

not once, but twice, independently, in our solar system,

不知是一次，还是两次，在太阳系中其他星球

then that means, by inference, it has occurred a staggering number of times

意味着，通过推断，

throughout the universe and its 13.7 billion year history.

在宇宙137亿年的历史上不断发生过

Right now, Earth is the only planet still that we know is teeming with life.

现在，地球是我们唯一知道的充满生机的行星

It is precious, it is unique,

是珍贵、独特的

it is still, so far, the only home we've ever known.

同时也是我们唯一的家园

And if any of you were alert and coherent during the 1960s --

对于警觉思辨的人来说上世纪60年代

and we'd forgive you, if you weren't, OK --

要不是那样的人也没关系

you would remember this very famous picture

要是你还记得那令人难忘的

taken by the Apollo 8 astronauts in 1968.

1968年阿波罗8号宇航员拍下的照片

It was the first time that Earth was imaged from space,

那是首张从太空中拍下的地球照片

and it had an enormous impact on our sense of place in the universe,

这张照片对我们行星的位置

and our sense of responsibility for the protection of our own planet.

以及保卫家园的责任感有了深刻冲击

Well, we on Cassini have taken an equivalent first,

可以说卡西尼第一条做到了

a picture that no human eye has ever seen before.

人类肉眼看不到的照片

It is a total eclipse of the Sun, seen from the other side of Saturn.

这是土星另一面看到的日蚀

And in this impossibly beautiful picture,

在这张没得令人窒息的照片中

you see the main rings backlit by the Sun,

那些光环被太阳的光辉点亮

you see the refracted image of the Sun

这是太阳的折射成像

and you see this ring created, in fact,

这些光环是土卫二的散发物

by the exhalations of Enceladus.

创造出来的

But as if that weren't brilliant enough, we can spot, in this beautiful image,

要是这些还不够美，那看看这些

sight of our own planet,

我们行星的图片

cradled in the arms of Saturn's rings.

被土星的光环所环抱

Now, there is something deeply moving

从远处看我们的家园

about seeing ourselves from afar,

是很感人的

and capturing the sight of our little, blue-ocean planet

在外太空

in the skies of other worlds.

拍下我们海蓝的行星

And that, and the perspective of ourselves that we gain from that,

也许这场长达半个世纪的探索

may be, in the end, the finest reward that we earn

追中给我们的奖励是

from this journey of discovery that started half a century ago.

对我们自己更深的认识

And thank you very much.

非常感谢

(Applause)

（鼓掌）