Name: 【TED】Lucianne Walkowicz: Let's not use Mars as a backup planet (Let's not use Mars as a backup planet | Lucianne Walkowicz)
Uploaded: 2017-06-26T04:55:44.000Z
Duration: 5 min 55 s
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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.

thousands of potential planets around other stars,

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

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.

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

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

our own planet is sagging under the weight of humanity.

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:

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

it might be considered a potentially habitable world

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.

resemble the deserts of our own home world,

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

Consider the extent to which we have not colonized

places that are lush by comparison with Mars.

Even in the driest, highest places on Earth,

exhaled from thousands of miles away by our rainforests.

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

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,

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

But the goals of interplanetary exploration and planetary preservation

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.

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

I leave you with a final thought experiment:

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.

Well, one possible solution to Fermi's paradox

is that, as civilizations become technologically advanced enough

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

It is hubris to believe that interplanetary colonization alone

but planetary preservation and interplanetary exploration

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【TED】Lucianne Walkowicz: Let's not use Mars as a backup planet (Let's not use Mars as a backup planet | Lucianne Walkowicz)

subtle

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potentially

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