Lets not use Mars as a backup planet Lucianne Walkowicz

We’re at a tipping point in human history,

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

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

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

NASA’s Kepler mission has discovered

thousands of potential planets
around other stars,

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

Kepler is a space telescope

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

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

Kepler’s data reveals planets' sizes

as well as their distance
from their parent star.

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

like the terrestrial planets
in our own Solar System,

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

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

might be habitable or not.

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

of potentially habitable worlds,

our own planet is sagging
under the weight of humanity.

2014 was the hottest year on record.

Glaciers and sea ice that have
been with us for millennia

are now disappearing
in a matter of decades.

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

are rapidly outpacing our ability
to alter their course.

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

I study planetary habitability
as influenced by stars

with the hopes of finding
the places in the universe

where we might discover
life beyond our own planet.

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

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

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

the more you appreciate
our own planet itself.

Each one of these new worlds
invites a comparison

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

those of our own Solar System.

Consider our neighbor, Mars.

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

it might be considered
a potentially habitable world

if found by a mission like Kepler.

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

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

Our rovers, like Curiosity,
crawl across its surface,

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

Orbiters like the MAVEN mission
sample the Martian atmosphere,

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

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

but the tantalizing possibility
of living our lives on Mars.

But though these Martian vistas

resemble the deserts
of our own home world,

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

compared to Earth

Mars is a pretty terrible place to live.

Consider the extent to which
we have not colonized

the deserts of our own planet,

places that are lush
by comparison with Mars.

Even in the driest,
highest places on Earth,

the air is sweet and thick with oxygen

exhaled from thousands of miles away
by our rainforests.

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

carries with it a long, dark shadow:

the implication and belief by some

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

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

As much as I love
interplanetary exploration,

I deeply disagree with this idea.

There are many excellent reasons
to go to Mars,

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

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

is happening later on the lifeboats.

(Laughter)

(Applause)

Thank you.

But the goals of interplanetary
exploration and planetary preservation

are not opposed to one another.

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

to understand, preserve
and improve life into the future.

The extreme environments
of our own world are alien vistas.

They’re just closer to home.

If we can understand how to create
and maintain habitable spaces

out of hostile, inhospitable
spaces here on Earth,

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

and moving beyond it.

I leave you with a final
thought experiment:

Fermi’s paradox.

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

that our universe has been around
for a very long time

and we expect that there
are many planets within it,

we should have found evidence
for alien life by now.

So where are they?

Well, one possible solution
to Fermi’s paradox

is that, as civilizations become
technologically advanced enough

to consider living amongst the stars,

they lose sight of how important it is

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

It is hubris to believe
that interplanetary colonization alone

will save us from ourselves,

but planetary preservation
and interplanetary exploration

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)

我们正处于人类历史的一个转折点,

一个处于获得恒星
和失去我们称之为家的星球之间的物种。

即使在过去的几年里,
我们也大大扩展

了我们对地球如何
适应我们宇宙环境的认识。

美国宇航局的开普勒任务在其他恒星周围发现了

数千颗潜在行星
,这

表明地球只是
我们银河系中数十亿颗行星之一。

开普勒是一台太空望远镜

,它可以测量恒星
在行星从它们前面经过时的微妙变暗,从而

阻止了一
点点光线到达我们。

开普勒的数据揭示了行星的大小

以及
它们与母星的距离。

总之,这有助于我们了解
这些行星是否


我们自己的太阳系中的类地行星一样小而多岩石,

以及
它们从母太阳接收到多少光。

反过来,这为
我们发现的这些行星

是否适合居住提供了线索。

不幸的是,在
我们发现这个

潜在可居住世界的宝库的同时,

我们自己的星球
在人类的重压下正在下垂。

2014 年是有记录以来最热的一年。

几千年来一直伴随着我们的冰川和海冰

现在
在几十年内就消失了。 我们已经启动的

这些行星规模的环境
变化

正在迅速超过我们
改变其进程的能力。

但我不是气候科学家,
我是天文学家。

我研究
受恒星影响的行星宜居性

,希望能
在宇宙

中找到我们可能
在我们自己的星球之外发现生命的地方。

你可以说我在寻找
外星人的房地产。

现在,作为一个深深植根
于寻找宇宙生命的人,

我可以告诉你,
你越是寻找像地球这样的行星

,你就越欣赏
我们自己的星球本身。

这些新世界中的每一个都
邀请我们

将新发现
的行星与我们最了解的行星进行比较

:我们自己的太阳系的行星。

想想我们的邻居,火星。

火星很小而且多岩石
,虽然它离太阳有点远,

但如果像开普勒这样的任务发现它可能会被认为
是一个潜在的宜居世界

事实上,火星过去很可能
是宜居的

,这也是
我们如此深入研究火星的部分原因。

我们的漫游者,就像好奇号一样,
爬过它的表面,

寻找关于
我们所知道的生命起源的线索。

像 MAVEN 任务这样的轨道器
对火星大气进行采样,

试图了解火星
是如何失去过去的可居住性的。

私人航天公司现在不仅提供
到近太空的短途旅行,还提供

我们在火星上生活的诱人可能性。

但是,尽管这些火星景观

类似于
我们自己家园世界的沙漠,这些

地方在我们的想象
中与关于开拓和前沿的想法联系在一起,但

与地球相比,

火星是一个非常糟糕的居住地。

想想我们在
多大程度上没有在

我们自己星球的沙漠中殖民,这些

地方
与火星相比更加茂盛。

即使在地球上最干燥、
海拔最高的地方

,空气也是甜美而浓密的,空气中

充满了我们的热带雨林从数千英里外呼出的氧气

我担心——我
担心殖民火星和其他行星的兴奋

带来了一个漫长而黑暗的阴影

:一些人暗示和

相信火星将在那里拯救我们
免于

对唯一真正可居住的星球造成的自我毁灭
我们知道,地球。

尽管我很喜欢
星际探索,但

我非常不同意这个想法。 去火星

有很多很好的理由

但是任何人告诉你火星
会在那里支持

人类,就像泰坦尼克号的船长
告诉你真正的派对将

在稍后的救生艇上举行。

(笑声)

(掌声)

谢谢。

但是星际
探索和行星保护

的目标并不相互对立。

不,它们实际上
是同一个目标的两个方面

:理解、保护
和改善未来的生活。

我们自己世界的极端环境是外星人的景象。

他们只是离家更近。

如果我们能够理解如何在地球

上充满敌意、荒凉的
空间中创造和维持可居住的空间,

也许我们
可以满足保护我们自己的环境

和超越它的需求。

我留给你一个最后的
思想实验:

费米悖论。

许多年前,物理学家恩里科·费米(Enrico Fermi)
提出,

鉴于我们的宇宙已经
存在了很长时间,

并且我们预计其中
有许多行星,

我们现在应该已经找到
了外星生命的证据。

那么他们在哪里呢?

好吧,
费米悖论的一个可能解决方案

是,随着文明变得
足够先进,

可以考虑生活在星际之中,

他们忽视

了保护
从一开始就促进了这种进步的家园世界的重要性。

认为仅行星际殖民就能

将我们从自己手中拯救出来是自大的,

但行星保护
和行星际探索

可以协同工作。

如果我们真的相信我们有能力

改变火星恶劣的环境以
供人类居住,

那么我们应该能够克服
保护地球宜居性这一更容易的任务

谢谢你。

(掌声)