0:00:01.072,0:00:04.897
I'm here to tell you about [br]the real search for alien life.

0:00:04.897,0:00:07.930
Not little green humanoids[br]arriving in shiny UFOs,

0:00:07.930,0:00:09.678
although that would be nice.

0:00:09.678,0:00:11.488
But it's the search for planets

0:00:11.488,0:00:14.056
orbiting stars far away.

0:00:14.056,0:00:15.783
Every star in our sky is a sun.

0:00:15.783,0:00:17.161
And if our sun has planets --

0:00:17.161,0:00:18.798
Mercury, Venus, Earth, Mars, etc.

0:00:18.798,0:00:21.434
Surely those other stars should[br]have planets also

0:00:21.434,0:00:23.293
-- and they do.

0:00:23.293,0:00:24.701
And in the last two decades,

0:00:24.701,0:00:28.713
astronomers have found[br]thousands of exoplanets.

0:00:28.713,0:00:31.337
Our night sky is literally[br]teeming with exoplanets.

0:00:31.337,0:00:32.913
We know, statistically speaking,

0:00:32.913,0:00:36.152
that every star has at least one planet.

0:00:36.152,0:00:37.985
And in the search for planets,

0:00:37.985,0:00:40.775
and in the future, planets [br]that might be like earth,

0:00:40.775,0:00:42.168
we're able to help address[br]

0:00:42.168,0:00:44.872
some of the most amazing[br]and mysterious questions

0:00:44.872,0:00:47.987
that have faced humankind for centuries.

0:00:47.987,0:00:49.390
Why are we here?

0:00:49.390,0:00:51.607
Why does our universe exist?

0:00:51.607,0:00:54.073
How did earth form and evolve?

0:00:54.073,0:00:57.880
How and why did life originate[br]and populate our planet?

0:00:57.880,0:01:00.555
The second question that[br]we often think about is:

0:01:00.555,0:01:03.039
Are we alone?

0:01:03.039,0:01:05.317
Is there life out there?

0:01:05.317,0:01:07.300
Who is out there?

0:01:07.300,0:01:09.190
You know, this question[br]has been around

0:01:09.190,0:01:10.413
for thousands of years,

0:01:10.413,0:01:12.942
since at least the time[br]of the Greek philosophers.

0:01:12.942,0:01:15.550
But, I'm here to tell you[br]just how close we're getting

0:01:15.550,0:01:18.447
to finding out the answer[br]to this question.

0:01:18.447,0:01:20.264
It's the first time in human history

0:01:20.264,0:01:22.969
that this really is within reach for us.

0:01:22.969,0:01:24.975
Now when I think about[br]the possibilities

0:01:24.975,0:01:26.297
for life out there,

0:01:26.297,0:01:28.550
I think of the fact that our sun

0:01:28.550,0:01:30.825
is but one of many stars.

0:01:30.825,0:01:32.727
This is a photograph of a real galaxy,

0:01:32.727,0:01:35.197
we think our milky way [br]looks like this galaxy.

0:01:35.197,0:01:37.031
It's a collection of bound stars.

0:01:37.031,0:01:41.271
But our milky way is one of[br]hundreds of billions of stars

0:01:41.271,0:01:45.619
and our galaxy is one of upwards[br]of hundreds of billions of galaxies.

0:01:45.619,0:01:49.498
Knowing that small planets [br]are very common,

0:01:49.498,0:01:52.035
you can just do the math.

0:01:52.035,0:01:55.449
And there are just so many stars[br]and so many planets out there,

0:01:55.449,0:01:58.777
that surely, there must be life[br]somewhere out there.

0:01:58.777,0:02:02.742
Well, the biologists get furious [br]with me for saying that,

0:02:02.742,0:02:05.082
because we have absolutely no evidence.[br]

0:02:05.082,0:02:07.231
for life beyond earth, yet.

0:02:07.231,0:02:10.815
Well, if we were able to look[br]at our galaxy from the outside

0:02:10.815,0:02:14.026
and zoom in to where our sun is,

0:02:14.026,0:02:16.196
we see a real map of the stars.

0:02:16.196,0:02:19.004
And the highlighted stars are[br]those with known exoplanets.

0:02:19.004,0:02:22.860
This is really just[br]the tip of the iceberg.

0:02:22.860,0:02:26.801
Here, this animation is zooming in[br]onto our solar system.

0:02:26.801,0:02:28.381
And you'll see here the planets[br]

0:02:28.381,0:02:31.583
as well as some spacecraft[br]that are also orbiting our sun.

0:02:31.583,0:02:35.553
Now if we can imagine going to[br]the west coast of North America,

0:02:35.553,0:02:38.723
and looking out at the night sky,[br]

0:02:38.723,0:02:40.808
here's what we'd see on a spring night.

0:02:40.808,0:02:42.842
And you can see[br]the constellations overlaid

0:02:42.842,0:02:45.313
and again, so many stars with planets.

0:02:45.313,0:02:47.375
There's a special patch of the sky

0:02:47.375,0:02:49.353
where we have thousands of planets.

0:02:49.353,0:02:53.841
This is where the Kepler Space Telescope[br]focused for many years.

0:02:53.841,0:02:58.743
Let's zoom in and look at[br]one of the favorite exoplanets.

0:02:58.743,0:03:02.856
This star is called Kepler-186f.

0:03:02.856,0:03:04.603
It's a system of about five planets.

0:03:04.603,0:03:06.585
And by the way, most of these exoplanets,

0:03:06.585,0:03:08.802
we don't know too much about.

0:03:08.802,0:03:11.760
We know their size, and their orbit[br]and things like that.

0:03:11.760,0:03:15.796
But there's a very special planet[br]here called Kepler-186f,

0:03:15.796,0:03:19.721
this planet is in a zone that is not [br]too far from the star,

0:03:19.721,0:03:23.282
so that the temperature may be [br]just right for life.

0:03:23.282,0:03:25.587
Here, the artist conniption[br]is just zooming in

0:03:25.587,0:03:28.936
and showing you what that planet[br]might be like.

0:03:31.186,0:03:36.949
So, many people have this[br]romantic notion of astronomers

0:03:36.949,0:03:40.280
going to the telescope[br]on a lonely mountaintop

0:03:40.280,0:03:42.407
and looking at the spectacular night sky

0:03:42.407,0:03:44.089
through a big telescope.

0:03:44.089,0:03:47.465
But actually, we just work on[br]our computers like everyone else

0:03:47.465,0:03:50.906
and we get our data by email[br]or by loading from a database.

0:03:50.906,0:03:53.048
So instead of coming here [br]to tell you about

0:03:53.048,0:03:56.800
the somewhat tedious nature [br]of the data and data analysis

0:03:56.800,0:03:58.890
and the complex computer models we make,

0:03:58.890,0:04:01.258
I have a different way to try [br]to explain to you

0:04:01.258,0:04:03.178
some of the things that we're [br]thinking about exoplanets.

0:04:03.178,0:04:04.909
Here's a travel poster:

0:04:04.909,0:04:07.315
"Kepler-186f,

0:04:07.315,0:04:10.234
Where the grass is always redder [br]on the other side."

0:04:10.234,0:04:13.001
That's because Kepler-186f[br]orbits a red star,

0:04:13.001,0:04:16.323
and we're just speculating that[br]perhaps the plants there,

0:04:16.323,0:04:19.165
if there is vegetation that [br]does photosynthesis,

0:04:19.165,0:04:22.296
it has different pigments and looks red.

0:04:22.296,0:04:26.519
"Enjoy the gravity on HD 40307g, "

0:04:26.519,0:04:28.189
a super-earth.

0:04:28.189,0:04:30.183
This planet is more massive than earth

0:04:30.183,0:04:32.496
and has a higher surface gravity.

0:04:32.496,0:04:35.419
"Relax on Kepler-16b,

0:04:35.419,0:04:38.173
where your shadow always has company."

0:04:38.173,0:04:43.544
We know of a dozen planets[br]that orbit two stars,

0:04:43.544,0:04:45.507
and there's likely many more out there.

0:04:45.507,0:04:47.689
If we could visit one of those planets,

0:04:47.689,0:04:49.599
you literally would see two sunsets

0:04:49.599,0:04:51.436
and have two shadows.

0:04:51.436,0:04:53.970
So actually, science fiction [br]got some things right,

0:04:53.970,0:04:55.765
Tatooine from Star Wars.

0:04:55.765,0:04:58.142
And I have a couple of other [br]favorite exoplanets

0:04:58.142,0:04:59.771
to tell you about.

0:04:59.771,0:05:01.392
This one is Kepler-10b,

0:05:01.392,0:05:03.797
it's a hot, hot planet.

0:05:03.797,0:05:06.601
It orbits over 50 times [br]closer to its star

0:05:06.601,0:05:08.964
than the earth does to our sun.

0:05:08.964,0:05:10.396
And actually, it's so hot

0:05:10.396,0:05:13.053
we can't visit any of these planets,[br]but if we could,

0:05:13.053,0:05:15.051
we would melt long before[br]we got there.

0:05:15.051,0:05:17.404
We think the surface is[br]hot enough to melt rock

0:05:17.404,0:05:19.672
and has liquid lava lakes.

0:05:19.672,0:05:21.065
We use 1214b.

0:05:21.065,0:05:23.188
This planet, we know the mass[br]and the size

0:05:23.188,0:05:24.800
and it has a fairly low density.

0:05:24.800,0:05:25.970
it's somewhat warm.

0:05:25.970,0:05:28.635
We actually don't know really[br]anything about this planet.

0:05:28.635,0:05:31.290
One possibility is that [br]it's a water world,

0:05:31.290,0:05:34.529
like a scaled-up version of one[br]of Jupiter's icy moons

0:05:34.529,0:05:37.551
that might be 50 percent water by mass.

0:05:37.551,0:05:40.313
In this case, it would have[br]a thick steam atmosphere

0:05:40.313,0:05:42.514
overlaying an ocean,

0:05:42.514,0:05:43.727
not of liquid water,

0:05:43.727,0:05:45.947
but of an exotic form of water,

0:05:45.947,0:05:46.756
a superfluid --

0:05:46.756,0:05:48.770
not quite a gas, not quite a liquid.

0:05:48.770,0:05:50.294
Under that wouldn't be rock,

0:05:50.294,0:05:54.713
but a form of high pressure ice, [br]like ice-nine.

0:05:54.713,0:05:56.956
So out of all these planets out there,

0:05:56.956,0:06:00.275
and the variety is [br]just simply astonishing,

0:06:00.275,0:06:02.118
we mostly want to find the planets

0:06:02.118,0:06:05.184
that are Goldielocks planets,[br]we call them,

0:06:05.184,0:06:07.125
not too big, not too small

0:06:07.125,0:06:08.996
not too hot, not too cold --

0:06:08.996,0:06:10.369
but just right for life.

0:06:10.369,0:06:12.500
But to do that, we'd have to [br]be able to look

0:06:12.500,0:06:14.039
at the planet's atmosphere

0:06:14.039,0:06:16.058
because the atmosphere acts[br]like a blanket

0:06:16.058,0:06:16.978
trapping heat --

0:06:16.978,0:06:18.338
the greenhouse effect.

0:06:18.338,0:06:21.182
We have to be able to asses[br]the greenhouse gasses

0:06:21.182,0:06:23.368
on other planets.

0:06:23.368,0:06:25.796
Well, science fiction got[br]some things wrong.

0:06:25.796,0:06:28.910
The Star Trek Enterprise [br]had to travel vast distances

0:06:28.910,0:06:32.333
at incredible speeds [br]to orbit other planets

0:06:32.333,0:06:35.817
so that First Officer Spok [br]could analyze

0:06:35.817,0:06:38.895
the atmosphere to see[br]if the planet was habitable

0:06:38.895,0:06:40.999
or if there were lifeforms there.

0:06:40.999,0:06:43.259
Well, we don't need[br]to travel at warp speeds

0:06:43.259,0:06:45.412
to see other planet atmospheres,

0:06:45.412,0:06:48.220
although I don't want to dissuade [br]any budding engineers

0:06:48.220,0:06:50.167
from figuring out how to do that.

0:06:50.167,0:06:52.483
We actually can and do study[br]planet atmospheres

0:06:52.483,0:06:54.120
from here, from earth orbit.

0:06:54.120,0:06:55.347
This is a picture, a photograph

0:06:55.347,0:06:57.321
of the Hubble Space Telescope

0:06:57.321,0:07:00.095
taken by the shuttle Atlantis[br]as it was departing

0:07:00.095,0:07:02.073
after the last human space [br]flight to Hubble.

0:07:02.073,0:07:03.926
They installed a new camera, actually,

0:07:03.926,0:07:06.640
that we use for exoplanet atmospheres.

0:07:06.640,0:07:11.366
And so far, we've been able to study[br]dozens of exoplanet atmospheres,

0:07:11.366,0:07:13.514
about six of them in great detail.

0:07:13.514,0:07:15.710
But those are not [br]small planets like earth.

0:07:15.710,0:07:18.128
They're big, hot planets[br]that are easy to see.

0:07:18.128,0:07:19.190
We're not ready,

0:07:19.190,0:07:21.068
we don't have the right technology yet

0:07:21.068,0:07:23.789
to study small exoplanets.

0:07:23.789,0:07:25.160
But nevertheless,

0:07:25.160,0:07:26.916
I wanted to try to explain to you

0:07:26.916,0:07:29.874
how we study exoplanet atmospheres.

0:07:29.874,0:07:32.748
I want you to imagine,[br]for a moment, a rainbow.

0:07:32.748,0:07:35.515
And if we could look [br]at this rainbow closely,

0:07:35.515,0:07:39.287
we would see that some[br]dark lines are missing.

0:07:39.287,0:07:40.572
And here's our sun,

0:07:40.572,0:07:42.523
the white light of our sun split up,

0:07:42.523,0:07:44.673
not by raindrops, but by a spectrograph.

0:07:44.673,0:07:47.148
And you can see [br]all these dark, vertical lines.

0:07:47.148,0:07:48.726
Some are narrow, some are wide,

0:07:48.726,0:07:50.883
some are shaded at the edges.

0:07:50.883,0:07:54.059
And this is how astronomers have studied[br]objects in the heavens,

0:07:54.059,0:07:55.812
literally, for over a century.

0:07:55.812,0:07:58.028
So here, each different atom and molecule

0:07:58.028,0:07:59.577
has a special set of lines,

0:07:59.577,0:08:01.157
a fingerprint, if you will.

0:08:01.157,0:08:03.544
And that's how we study[br]exoplanet atmospheres.

0:08:03.544,0:08:05.902
And, I'll just never forget[br]when I started working

0:08:05.902,0:08:08.187
on exoplanet atmospheres[br]20 years ago,

0:08:08.187,0:08:09.553
how many people told me,

0:08:09.553,0:08:11.491
"This will never happen,[br]we'll never be able to study them.

0:08:11.491,0:08:13.038
Why are you bothering?"

0:08:13.038,0:08:14.674
And so that's why I'm pleased [br]to tell you about

0:08:14.674,0:08:16.232
all the atmospheres studied now,

0:08:16.232,0:08:18.723
and this is really a whole field[br]of its own.

0:08:18.723,0:08:21.555
So when it comes to[br]other planets, other earths,

0:08:21.555,0:08:23.656
in the future when we can observe them,

0:08:23.656,0:08:26.373
what kind of gasses would be looking for?

0:08:26.373,0:08:29.343
Well, you know, our own earth [br]has oxygen in the atmosphere

0:08:29.343,0:08:31.689
to 20 percent by volume.

0:08:31.689,0:08:33.457
That's a lot of oxygen.

0:08:33.457,0:08:35.811
But without plants [br]and photosynthetic life,

0:08:35.811,0:08:37.660
there would be no oxygen,[br]

0:08:37.660,0:08:40.299
virtually no oxygen in our atmosphere.

0:08:40.299,0:08:42.063
So oxygen is here because of life.

0:08:42.063,0:08:44.102
And our goal then is to look for gasses

0:08:44.102,0:08:46.194
in other planet atmospheres,

0:08:46.194,0:08:48.255
gasses that don't belong,

0:08:48.255,0:08:50.662
that we might be able [br]to attribute to life.

0:08:50.662,0:08:52.767
But which molecules should [br]we search for?

0:08:52.767,0:08:55.454
I actually told you how diverse[br]exoplanets are.

0:08:55.454,0:08:57.375
We expect that to continue in the future

0:08:57.375,0:08:58.888
when we find other earths.

0:08:58.888,0:09:00.619
And that's one of the main things[br]I'm working on now,

0:09:00.619,0:09:02.892
I have a theory about this.

0:09:02.892,0:09:05.237
It reminds me that nearly everyday,

0:09:05.237,0:09:06.492
I receive an email --

0:09:06.492,0:09:07.424
email or emails--

0:09:07.424,0:09:11.745
from someone with a crazy theory[br]about physics of gravity

0:09:11.745,0:09:13.424
or cosmology or some such.

0:09:13.424,0:09:18.023
Please don't email me[br]one of your crazy theories.

0:09:18.023,0:09:20.209
Well, I had my own crazy theory.

0:09:20.209,0:09:23.077
But, who does the MIT professor go to?

0:09:23.077,0:09:26.938
Well I emailed a Nobel Laureate [br]in physiology and medicine

0:09:26.938,0:09:28.935
and he said, "Sure, come and talk to me."

0:09:28.935,0:09:30.858
So I brought my two biochemistry friends

0:09:30.858,0:09:33.234
and we went to talk to him[br]about our crazy theory.

0:09:33.234,0:09:36.799
And that theory was that life produces[br]all small molecules,

0:09:36.799,0:09:38.497
so many molecules.

0:09:38.497,0:09:41.337
Like, everything I could think of,[br]but not being a chemist.

0:09:41.337,0:09:42.423
Think about it:

0:09:42.423,0:09:44.677
carbon dioxide, carbon monoxide,

0:09:44.677,0:09:46.835
molecular hydrogen, molecular nitrogen,

0:09:46.835,0:09:47.723
methane, methal choloride (?) --

0:09:47.723,0:09:48.822
so many gasses,

0:09:48.822,0:09:51.094
they also exist for other reasons,

0:09:51.094,0:09:53.117
but just life even produces ozone.

0:09:53.117,0:09:54.927
So we go to talk to him about this,

0:09:54.927,0:09:56.918
and immediately, he shot down the theory.[br]

0:09:56.918,0:09:59.517
He found an example that didn't exist.

0:09:59.517,0:10:01.553
So, we went back to the drawing board

0:10:01.553,0:10:03.973
and we actually think we have[br]found something very interesting

0:10:03.973,0:10:05.337
in another field.

0:10:05.337,0:10:06.649
But back to exoplanets,

0:10:06.649,0:10:09.952
the point is that life produces[br]so many different types of gases,

0:10:09.952,0:10:12.188
literally thousands of gasses.

0:10:12.188,0:10:14.762
And so what we're doing now [br]is just trying to figure out

0:10:14.762,0:10:16.492
on which types of exoplanets,

0:10:16.492,0:10:20.892
which gasses could be attributed to life.

0:10:22.032,0:10:24.254
And so when it comes time[br]when we find gasses

0:10:24.254,0:10:25.629
on exoplanet atmospheres,[br]

0:10:25.629,0:10:27.577
that we won't know if they're [br]being produced

0:10:27.577,0:10:29.987
by intelligent aliens or by trees,

0:10:29.987,0:10:32.037
or earth(?) swamp,

0:10:32.037,0:10:35.757
or even just by simple, [br]single-celled microbial life.

0:10:35.757,0:10:36.992
And so working on the models

0:10:36.992,0:10:38.790
and thinking about biochemistry

0:10:38.790,0:10:40.011
it's all well and good.

0:10:40.011,0:10:42.911
But a really big challenge[br]ahead of us is how.

0:10:42.920,0:10:44.834
How are we going to find these planets?

0:10:44.834,0:10:46.994
They're actually many [br]ways to find planets,

0:10:46.994,0:10:48.853
several different ways.

0:10:48.853,0:10:50.676
But the one that I'm most focused on

0:10:50.676,0:10:52.736
is how can we open a gateway

0:10:52.736,0:10:53.997
so that in the future,

0:10:53.997,0:10:56.094
we can find hundreds of earths.

0:10:56.094,0:10:58.447
We have a real shot[br]at finding signs of life.

0:10:58.447,0:11:01.508
And actually, I just finished[br]leading a two-year project

0:11:01.508,0:11:04.391
in this very special phase[br]of a concept

0:11:04.391,0:11:06.167
we call the Starshade.

0:11:06.167,0:11:09.144
And the Starshade is very[br]specially shaped screen

0:11:09.144,0:11:11.035
and the goal is to fly that Starshade

0:11:11.035,0:11:14.153
so it blocks out the light of a star

0:11:14.153,0:11:17.116
so that a telescope can see [br]the planets directly.

0:11:17.116,0:11:19.533
Here, you can see myself [br]and two team members

0:11:19.533,0:11:21.624
holding up one small part[br]of the Starshade.

0:11:21.624,0:11:23.350
It's shaped like a giant flower,

0:11:23.350,0:11:27.160
and this is one of the prototype petals.

0:11:27.160,0:11:31.598
The concept is that a star shade [br]and telescope launch together,

0:11:31.598,0:11:35.150
with the petals unfurling[br]from the stowed position.

0:11:35.150,0:11:37.222
The central trust(?) would expand,

0:11:37.222,0:11:40.092
with the petals snapping into place.

0:11:40.092,0:11:42.346
Now, this has to be made very precisely,

0:11:42.346,0:11:43.958
literally, the petals to microns

0:11:43.958,0:11:46.697
and they have to deploy to millimeters.

0:11:46.697,0:11:48.776
And this hole structure would have to fly

0:11:48.776,0:11:50.466
tens of thousands of kilometers

0:11:50.466,0:11:51.672
away from the telescope.

0:11:51.672,0:11:53.730
it's about tens of meters in diameter.

0:11:53.730,0:11:58.783
And the goal is to block out[br]the starlight to incredible precision

0:11:58.783,0:12:03.006
so that we'd be able to see [br]the planets directly.

0:12:03.006,0:12:05.084
It has to be a very special shape

0:12:05.084,0:12:07.245
because of the physics of defraction.

0:12:07.245,0:12:09.742
Now this is a really project [br]that we worked on,

0:12:09.742,0:12:12.234
literally, you would not believe how hard.

0:12:12.234,0:12:14.920
Just so you believe that it's [br]not just in movie format,

0:12:14.920,0:12:18.186
here's a real photograph[br]of a second generation

0:12:18.186,0:12:20.930
Starshade deployment [br]test bed in the lab.

0:12:20.930,0:12:22.044
And in this case,

0:12:22.044,0:12:23.498
I just wanted you to know,

0:12:23.498,0:12:25.793
that that central trust[br]has heritage left over

0:12:25.793,0:12:28.999
from large radio deployables in space.

0:12:28.999,0:12:31.052
So after all of that hard work

0:12:31.052,0:12:33.555
where we try to think of all [br]the crazy gasses

0:12:33.555,0:12:34.765
that might be out there,

0:12:34.765,0:12:37.215
and we build the very[br]complicated space telescopes

0:12:37.215,0:12:38.519
that might be out there,

0:12:38.519,0:12:41.039
what are we going to find?

0:12:41.039,0:12:42.507
Well, in the best case,

0:12:42.507,0:12:46.554
we will find an image [br]of another exo-earth.

0:12:46.554,0:12:48.611
Here's earth as a pale blue dot.

0:12:48.611,0:12:51.194
This is actually a real photograph[br]of earth

0:12:51.194,0:12:53.321
taken by the Voyager 1 spacecraft,

0:12:53.321,0:12:55.536
four billion miles away.

0:12:55.536,0:12:59.315
And that red light is just scattered light[br]in the camera optics.

0:12:59.315,0:13:02.516
But what's so awesome to consider is that[br]

0:13:02.516,0:13:07.206
if there are intelligent aliens[br]orbiting on a planet

0:13:07.206,0:13:08.786
around a star near to us

0:13:08.786,0:13:10.855
and they build complicated[br]space telescopes

0:13:10.855,0:13:12.911
of a kind that we're trying to build,

0:13:12.911,0:13:15.589
all they'll see is this pale blue dot,

0:13:15.589,0:13:17.727
a pinprick of light.

0:13:17.727,0:13:20.869
And so sometimes when [br]I pause to think about

0:13:20.869,0:13:24.733
my professional struggle[br]and huge ambition,

0:13:24.733,0:13:27.601
it's hard to think about [br]that in contrast

0:13:27.601,0:13:30.351
to the vastness of the universe.

0:13:30.351,0:13:33.912
But nonetheless, I am devoting[br]the rest of my life

0:13:33.912,0:13:36.439
to finding another earth.

0:13:36.439,0:13:39.868
And I can guarantee that in [br]the next generation

0:13:39.868,0:13:40.942
of space telescopes,

0:13:40.942,0:13:42.506
and the second generation,

0:13:42.506,0:13:46.855
we will have the capability to find[br]and identity other earths.

0:13:46.855,0:13:49.019
And the capability [br]to split up the starlight

0:13:49.019,0:13:52.211
so that we can look for gasses

0:13:52.211,0:13:55.541
and assess the greenhouse gasses[br]in the atmosphere,

0:13:55.541,0:13:57.343
estimate the surface temperature,

0:13:57.343,0:14:00.009
and look for signs of life.

0:14:00.009,0:14:01.076
But there's more,

0:14:01.076,0:14:03.742
in this case of searching[br]for other planets like earth,

0:14:03.742,0:14:07.413
we are making a new kind of map

0:14:07.413,0:14:10.472
of the nearby stars and [br]of the planets orbiting them,

0:14:10.472,0:14:15.244
including stars that actually might be[br]inhabitable by humans.

0:14:15.244,0:14:17.670
And so I envision that our descendants,

0:14:17.670,0:14:19.149
hundreds of years from now,

0:14:19.149,0:14:21.513
will embark on an interstellar journey

0:14:21.513,0:14:23.059
to other worlds.

0:14:23.059,0:14:26.261
And they will look back at all of us

0:14:26.261,0:14:29.894
as the generation who first found[br]the earth-like worlds.

0:14:29.894,0:14:30.785
Thank you.

0:14:30.785,0:14:37.794
(Applause)

0:14:37.794,0:14:38.970
June Cohen: And I give you, [br]for a question,

0:14:38.970,0:14:41.759
Rosetta Mission manager Fred Jansen.

0:14:41.759,0:14:43.434
Fred Jansen: You mentioned halfway through

0:14:43.434,0:14:47.683
that the technology to actually look[br]at the spectrum

0:14:47.683,0:14:50.736
of an exoplanet-like earth[br]is not there yet.

0:14:50.736,0:14:52.360
When do you expect this will be there

0:14:52.360,0:14:53.865
and what's needed?

0:14:53.865,0:14:55.620
Sara Seager: Well actually, [br]what we expect is what[br]

0:14:55.620,0:14:58.748
we call our next-generation[br]Hubble telescope.

0:14:58.748,0:15:00.593
And this is called the [br]James Webb Space Telescope,

0:15:00.593,0:15:03.043
and that will launch in 2018

0:15:03.043,0:15:04.459
and that's what we're going to do,

0:15:04.459,0:15:06.097
we're going to look at [br]a speicla kind of planet

0:15:06.097,0:15:07.857
called transient exoplanets,

0:15:07.857,0:15:09.642
and that will be our first shot

0:15:09.642,0:15:11.423
at studying small plants [br]for gasses that might indicate

0:15:11.423,0:15:12.602
the planet is habitable.

0:15:12.602,0:15:18.210
JC: I'm going to ask you one[br]follow-up question, too, Sara,

0:15:18.210,0:15:19.431
as the generalist.

0:15:19.431,0:15:22.657
So I am really struck by the notion[br]in your career

0:15:22.657,0:15:24.216
of the opposition you faced,

0:15:24.216,0:15:25.983
that when you began thinking about[br]exoplanets,

0:15:25.983,0:15:28.422
there was extreme skepticism[br]in the scientific community

0:15:28.422,0:15:29.226
that they existed,

0:15:29.226,0:15:30.826
and you proved them wrong.

0:15:30.826,0:15:33.143
What did it take to take that on?

0:15:33.143,0:15:36.457
SS: Well, the thing is that[br]as scientists,

0:15:36.457,0:15:37.219
we're supposed to be skeptical.

0:15:37.219,0:15:39.520
It's our job to make sure that[br]what the other peson is saying

0:15:39.520,0:15:41.164
makes sense or not.

0:15:41.164,0:15:43.814
But being a scientist,

0:15:43.814,0:15:46.518
I think you've seen it[br]from this session,

0:15:46.518,0:15:48.611
it's like being an explorer.

0:15:48.611,0:15:50.398
You have this immense curiosity,

0:15:50.398,0:15:51.721
this stubbornness,

0:15:51.721,0:15:54.127
this sort of resolute will[br]that you will go forward

0:15:54.127,0:15:56.633
no matter what people say.

0:15:56.633,0:15:57.764
JC: I love that. [br]Thank you, Sara.

0:15:57.764,0:16:02.039
(Applause)