a species poised between gaining the stars and losing the planet we call home.

我們正處在人類歷史上 的一個轉折點，

Even in just the past few years, we've greatly expanded

人類正徘迴在「取得」其它星球及「失去」 我們稱之為家的地球之間。

our knowledge of how Earth fits within the context of our universe.

即使在過去的幾年中，我們對於

NASA's Kepler mission has discovered

地球如何在宇宙中生存的 知識已經有大幅度的擴展。

thousands of potential planets around other stars,

美國太空總署(NASA)的Kepler任務 已經在銀河系發現

indicating that Earth is but one of billions of planets in our galaxy.

成千上萬的潛在行星 圍繞著其它恆星，

Kepler is a space telescope

並指出地球在銀河系數十億行星裡 並非是唯一的行星。

that measures the subtle dimming of stars as planets pass in front of them,

Kepler是一個太空望遠鏡，

blocking just a little bit of that light from reaching us.

藉由行星從恆星前方掠過的「凌日現象」

Kepler's data reveals planets' sizes

來鎖定觀察恆星 少許的亮度變化。

as well as their distance from their parent star.

Kepler的數據揭示了行星的大小

Together, this helps us understand whether these planets are small and rocky,

以及它們與直系恆星之間的距離。

like the terrestrial planets in our own Solar System,

總之，這有助於我們了解這些行星

and also how much light they receive from their parent sun.

是否像是我們太陽系裡的類地行星 具有小及岩石多樣性的特性。

In turn, this provides clues as to whether these planets that we discover

以及了解它們從它們的 直系太陽接收到多少光。

might be habitable or not.

因此這提供了我們 所發現的這些行星

Unfortunately, at the same time as we're discovering this treasure trove

是否適合居住的線索。

of potentially habitable worlds,

不幸的是，當我們在探索其他

our own planet is sagging under the weight of humanity.

適合人居的珍貴世界的同時，

2014 was the hottest year on record.

我們自己的地球也正在 急速地失去它的人性。

Glaciers and sea ice that have been with us for millennia

2014年是紀錄中最熱的一年，

are now disappearing in a matter of decades.

與我們相處好幾千年的冰川和海冰

These planetary-scale environmental changes that we have set in motion

在近幾十年裡， 一直在消失中...

are rapidly outpacing our ability to alter their course.

這些由我們造成 行星級規模的環境變化

But I'm not a climate scientist, I'm an astronomer.

正將快速地超越我們扭轉 它們既定方向的能力。

I study planetary habitability as influenced by stars

但我不是一個氣候學家， 我是一個天文學家。

with the hopes of finding the places in the universe

我研究行星受恆星影響的適居性，

where we might discover life beyond our own planet.

在宇宙中尋找一個可能有 非地球生命地方的希望之地。

You could say that I look for choice alien real estate.

你可以這樣說，我期待選擇 「外星人不動產仲介」...

Now, as somebody who is deeply embedded in the search for life in the universe,

身為一個大量投入 在宇宙中尋找生命的人，

I can tell you that the more you look for planets like Earth,

我可以告訴各位， 你越是想尋找像地球的行星

the more you appreciate our own planet itself.

你會越珍惜我們的地球。

Each one of these new worlds invites a comparison

每一個新發現的世界 都會被拿來做比較，

between the newly discovered planet and the planets we know best:

比較新發現的行星與我們最孰悉的

those of our own Solar System.

太陽系行星之間有甚麼差別。

Consider our neighbor, Mars.

想想我們的鄰居，火星...

Mars is small and rocky, and though it's a bit far from the Sun,

火星，既小又具岩石多樣性， 雖然離太陽有點遠，

it might be considered a potentially habitable world

它如果被Kepler任務發現的話，

if found by a mission like Kepler.

可能也會被認為是一個 潛在的可居住世界，

Indeed, it's possible that Mars was habitable in the past,

的確，過去火星可能具有可居住性， 雖只有某些部分，

and in part, this is why we study Mars so much.

但這也是為什麼 我們會研究火星的原因。

Our rovers, like Curiosity, crawl across its surface,

我們的火星車「好奇心號」 爬行過火星的表面，

scratching for clues as to the origins of life as we know it.

找到了我們認知的原始生命跡象。

Orbiters like the MAVEN mission sample the Martian atmosphere,

MAVEN任務的軌道飛行器 採集了火星上的大氣層樣本，

trying to understand how Mars might have lost its past habitability.

試著了解火星過去 是如何失去它的可居住性。

Private spaceflight companies now offer not just a short trip to near space

私人太空飛行公司現在 不只提供短暫的近太空旅行

but the tantalizing possibility of living our lives on Mars.

也提供生活在火星上誘人的可能性。

But though these Martian vistas

但是儘管這些火星景觀

resemble the deserts of our own home world,

類似於我們地球上的沙漠--

places that are tied in our imagination to ideas about pioneering and frontiers,

一些被我們的既有想像所限制 而不會想去開發的地方，

compared to Earth

相對於地球，

Mars is a pretty terrible place to live.

火星根本是一個糟糕到 無法住人的地方。

Consider the extent to which we have not colonized

比起火星，

the deserts of our own planet,

我們地球上還沒有開墾的沙漠地

places that are lush by comparison with Mars.

相對火星而言還是很奢侈的。

Even in the driest, highest places on Earth,

即是在地球最乾、最高的地方，

the air is sweet and thick with oxygen

從千里遠的雨林釋放出來 的氧氣仍是香甜而豐盛的。

exhaled from thousands of miles away by our rainforests.

我擔心-- 我擔心這種關於 火星和其他行星的殖民熱潮

I worry -- I worry that this excitement about colonizing Mars and other planets

會帶來漫長而黑暗的陰影：

carries with it a long, dark shadow:

一些人對火星有如此的隱喻和信仰--

the implication and belief by some

「當人類在我們唯一 真正能居住的地球上

that Mars will be there to save us from the self-inflicted destruction

發生自我毀滅衝突時， 火星會在那解救我們。」

of the only truly habitable planet we know of, the Earth.

我不同意這種想法的程度 就如我熱愛的星際探索一樣深，

As much as I love interplanetary exploration,

是有很多完美的因素要去火星，

I deeply disagree with this idea.

但要是哪一個人告訴你， 火星會在那裡拯救人類時...

There are many excellent reasons to go to Mars,

他就像鐵達尼號上的船長告訴你

but for anyone to tell you that Mars will be there to back up humanity

「等一下會有人開救生船來救你 」 一樣的胡扯。

is like the captain of the Titanic telling you that the real party

( 笑聲 )

is happening later on the lifeboats.

( 掌聲 )

(Laughter)

謝謝你

(Applause)

但星球探索與星球維護 這二件事的目標互不衝突，

Thank you.

雖然是二碼事， 但有共同目標 :

But the goals of interplanetary exploration and planetary preservation

在未來共同了解、 維護、改善生活。

are not opposed to one another.

我們地球上極端的環境 是外星人眼裡的美景。

No, they're in fact two sides of the same goal:

它們只是離家較近。

to understand, preserve and improve life into the future.

如果我們可以在自己的地球上

The extreme environments of our own world are alien vistas.

了解如何創造並維護友善的、 親切的可居住環境，

They're just closer to home.

也許我們可以滿足 既保護我們的環境

If we can understand how to create and maintain habitable spaces

又可以搬到外星球的需求。

out of hostile, inhospitable spaces here on Earth,

最後我告訴各位一個 思維實驗論述 :「費米謬論」。

perhaps we can meet the needs of both preserving our own environment

許多年前，物理學家 恩里科．費米提出了一個問題 :

and moving beyond it.

我們的宇宙已經 存在很久是個事實，

I leave you with a final thought experiment:

而我們也了解 有很多的行星在宇宙之中，

Fermi's paradox.

所以我們現在應該早就該 找到外星生命的證據...

Many years ago, the physicist Enrico Fermi asked that, given the fact

但他們在哪?

that our universe has been around for a very long time

「費米謬論」的 其中一種可能就是 :

and we expect that there are many planets within it,

一個存在於星際之間 科技相當先進的文明物種，

we should have found evidence for alien life by now.

他們一開始就忽視了如何 保護家園及培養進步的重要性。

So where are they?

所以去相信只靠星際殖民可以 解救我們的這件事是狂妄自大的。

Well, one possible solution to Fermi's paradox

星球維護與星際探索

is that, as civilizations become technologically advanced enough

可以一起進行。

to consider living amongst the stars,

如果我們真的相信我們有能力

they lose sight of how important it is

可以去扭轉火星的 惡劣環境來讓人類居住，

to safeguard the home worlds that fostered that advancement to begin with.

那麼我們應該可輕而易舉地克服

It is hubris to believe that interplanetary colonization alone

維護地球可居住性的 這項簡單任務。

will save us from ourselves,

謝謝你。

but planetary preservation and interplanetary exploration

( 掌聲 )

can work together.

If we truly believe in our ability

to bend the hostile environments of Mars for human habitation,

then we should be able to surmount the far easier task of preserving

the habitability of the Earth.

Thank you.

(Applause)