I'm here to tell you about
the real search
for alien life.
Not little green humanoids
arriving in shiny UFOs,
although that would be nice.
But it's the search for planets
orbiting stars far away.
Every star in our sky is a sun.
And if uur sun has planets --
Mercury, Venus, Earth, Mars, etc.
Surely those other stars should
have planets also
-- and they do.
And in the last two decades,
astronomers have found
thousands of exoplanets.
Our night sky is literally
teeming with exoplanets.
We know, statistically speaking,
that every star has at least one planet.
And in the search for planets,
and in the future, planets
that might be like earth,
we're able to help address
some of the most amazing
and mysterious questions
that have faced humankind for centuries.
Why are we here?
Why does our universe exist?
How did earth form and evolve?
How and why did life originate
and populate our planet?
The second question
that we often think about
is are we alone?
Is there life out there?
Who is out there?
You know, this question
has been around
for thousands of years,
since at least the time
of the Greek philosophers.
But, I'm here to tell you
just how close we're getting
to finding out the answer
to this question.
It's the first time in human history
that this really is within reach for us.
Now when I think about
the possibilities
for life out there,
I think of the fact that our sun
is one but many stars.
This is a photograph of a real galaxy,
we think our milky way
looks like this galaxy.
It's a collection of bound stars.
But our milky way is one of
hundreds of billions of stars
and our galaxy is one of upwards
of hundreds of billions of galaxies.
Knowing that small planets
are very common,
you can just do the math.
And there are just so many stars
and so many planets out there,
that surely, there must be life
somewhere out there.
Well, the biologists get furious
with me for saying that,
because we have absolutely
no evidence
for life beyond earth, yet.
Well, if we were able to look
at our galaxy from the outside
and zoom in to where our sun is,
we see a real map of the stars.
And the highlighted stars
are ones with known exoplanets,
this is really just
the tip of the iceberg.
Here, this animation is zooming in
onto our solar system.
And you'll see here some planets
as well as some spacecraft
that are also orbiting our sun.
Now if we can imagine
going to the west coast
of North America and looking out
on the night sky,
here's what we'd see on a spring night.
And you can see
the constellations overlaid
and again, so many stars with planets.
There's a special patch of the sky
where we have thousands of planets.
This is where the Kepler Space Telescope
focused for many years.
Let's zoom in and look at
one of the favorite exoplanets.
This star is called Kepler 180-6F.
It's a system of about five planets.
And by the way, most of these exoplanets,
we don't know too much about.
We know their size, and their orbit
and things like that.
But there's a very special planet
here called Kepler 180-6F,
this planet is in a zone that is not
too far from the star,
so that the temperature may be
just right for life.
Here, the ar