(French Music)
- [Paul Butler] The famous Italian monk Giordano Bruno
in 1586 published a book in which he said,
"the sun is a star and that the earth was a planet,
and that other stars certainly had planetary systems
and probably even had life."
And for that and other radical things that he said
the church burned him publicly.
You could say that extrasolar planets
was a much hotter field back then.
- [Debra Fischer] Exoplanets were almost as silly as
looking for extraterrestrials, you know, little green men
on other planets.
- [Didier Queloz] Seriously, looking for planets
was a kind of weird topic.
- The whole field had sort of a snake oil sheen about it
because over the previous 50 years or so there have been
many many claims of the first extrasolar planet ever
and the one thing all those claims had in common
was they were wrong.
- [Voiceover] In San Francisco, California, astronomers
Geoff Marcy and Paul Butler were quietly looking
for doppler shifts;
changes in the observed color of light from the star.
- I literally spent the first eight years of the program
simply trying to improve the techniques involved
in making these sort of measurements.
Mostly totally under the radar, nobody knew what we were doing
and nobody cared.
- [Voiceover] A ray of hope that it might be possible
to detect a planet came with the discovery by
Dave Latham and Tsevi Mazeh,
of a mysterious object orbiting the star HD114762.
- They announced the detection of an object
that they called a brown dwarf.
They looked, and they didn't see it in a telescope
so if it was a star
if it was a thousand times the mass of Jupiter,
they would have seen it.
- [Voiceover] To this day it is not known whether this object
is a planet, a brown dwarf or even a low-mass star.
But its discovery emboldened others to continue the search.
A different and dangerous approach to planet hunting
was underway in Canada.
The team of Gordon Walker and Bruce Campbell
employed the deadly gas Hydrogen Fluoride
in an attempt to precisely measure Doppler shifts.
- [Paul] And he showed me their setup in Canada at one point.
One person would be in there doing the setup.
And the other person would have been outside of the room
looking through a porthole with two gas masks.
And his job was if something went wrong, throw on a gas mask,
run into the room, throw the gas mask on the other guy
and drag him the hell out.
Any good science should have an element of danger.
There should always be at least
the vague hint of death involved.
Otherwise you're not really on the cutting edge.
They really pioneered the whole field.
Just a spectacular achievement.
- We're all here because of the work that they did.
- [Voiceover] In 1992, another incredible discovery piqued the
interest of astronomers looking for exoplanets.
But these knew exoplanets were not orbiting a regular star.
They were orbiting a pulsar.
- [Jill Tarter] Two very small bodies got detected at Arecibo
by Wolszczan and his colleagues.
And they really got us scratching our heads.
So, we call them pulsar planets.
- Wolszczan and Frail is somewhat of a special case
because I don't think anyone really doubted
that these were planets as much at the time,
but they were planets around a bizarre object, a pulsar.
- But they really were the first two bodies to orbit...
a dead star, not a currently shining star.
- The formation of planets is an incredibly robust process.
And that's what that discovery told us and we missed it
because we didn't understand it.
- We should've understood that planets don't come in one's,
that they come in systems,
but we were still focused on finding the very first planet.
- [Voiceover] Half way around the world in Geneva,
a pair of Swiss astronomers
were hard at work developing a different technique.
Their instrument relied on fiber optic technology,
and they used it to turn their eyes on exoplanets.
- My first day of work, I got this booklet from Michel
that was the ultimate knowledge of data processing
of spectroscopy, there was almost nothing at that time.
to do this, this instrument. And that's it, and we had
And we designed it, practically, without much support
from anybody else because the other people
felt that this was not interesting.
- [Michel Mayor] After a few months, already at the end
of '94, we got a signal of viability for several stars,
not only one, several stars.
- We realized very rapidly that the instrument
could be far more precise than we thought.
So I started with a couple of star a bit more intensively
and 51-Peg was one of them because it was bright.
And very rapidly, 51-Peg had a very weird behavior.
- On one side we were absolutely sure of the
quality of our measurement.
All the signal was in favor of a planet,
but it's evident it was a so unusual planet.
- I really thought at that time, oh there is something
really bad in the software and the instruments
and I better to figure out, because otherwise
my Phd will be compromised.
- [Voiceover] Over the next several months,
the two astronomers checked and re-checked their data.
The problem was no one could imagine a giant planet
with such a short orbit.
- So, we came back in July, this time together with Michel.
Very excited, I said okay, lo--let's see whether
the conclusion that we had with the first bunch of data
we had still holds.
- The real moment where we had the confirmation of the reality
of 51-Peg was really a planet was in July '95.
- First data up, just on it, We said, ok, just luck.
Second data, still on the curve.
We said, ok well two is far but still two is not enough.
The third one was still on it, following a track, I mean,
and then we say well, let's just wait the fourth...
to be really really sure.
Because it was so, so, so embarrassing conclusion
that planet that we really wanted to make sure that
that was real.
- We got the good period, the good amplitude and so on,
so at the time was really the time for the celebration.
Before we were not sure at that it was a planet.
- I mean there is a real planet.
Believe it or not, there is no theory to predict that planet,
but there is a planet there.
- [Voiceover] Following days of rumor circling the globe,
at a conference in Florence, Italy,
the news unofficially leaked.
A Jupiter-sized planet had been discovered.
This massive planet was making a complete orbit of its star
in only four days.
How could that be?
- Suddenly there's this 51-Peg which is a Jupiter-sized planet,
but in a four day orbit.
Well, people knew that was impossible.
Jupiter-like planets
orbit at like-Jupiter and Saturn orbital distances.
- [Voiceover] Back in San Francisco, Marcy and Butler,
by mere coincidence, had four consecutive days
of reserved telescope time at the Lick Observatory -
the exact amount of time needed to confirm or debunk the claim.
- [Paul] We hit the star very hard for those four nights.
We reduced the data as quickly as we can.
We were blown away.
We saw exactly the signal
that Mayor and Queloz had announced.
- Confirming my data,
to me was just the best gift I could have had.
Because I said, oh fine, so all the work I did is right.
- [News Announcer] Here in San Francisco the discovery
was dramatically verified just this past weekend
- [News Announcer] October 19th, 1995.
- [Ted Koppel] what may be the discovery of new planets
outside our solar system has created enormous excitement
among astronomers.
[Voiceover] The confirmation was made
before the official announcement of the discovery itself.
- It went completely out of control.
- Everybody was discussing of this new object except us.
- [Voiceover] By tradition, scientists have their
discoveries peer reviewed by other scientists for accuracy.
- [Alan Boss] I was one of the referees on the paper.
There were three referees.
And normally I think they only do two, but this was so big
that the Nature editor, Leslie Sage, was being very careful.
- Because of the situations, Nature was very strict.
They said "Well look guys, if you talk to people,
then we're not going to publish your paper."
- So, it's only after one month or something like this
that I receive a message from Nature that
ok, now you are relaxed from the embargo.
- Because the discovery of was just too big,
just far too big to follow the usual scheme
that is required for scientific paper.
As soon as you start talking about that,
I mean everybody wanted to know about this.
- 51 Peg B is a real planet, no question about that.
- As soon as we detected 51-Peg,
he had on his data plenty of something like that.
He just need to look at it.
- At this point we hadn't analyzed all our data.
We had two computers,
and it would have literally have taken us
five or six years to get through all of the data.
So, literally about a half a dozen different groups said
"You know we've just received these new computers and
we're not gonna use them for the next several months.
You wanna dump your jobs on it?"
- [Voiceover] Within two months, two other "Jupiters"
circling around their stars were found by Marcy and Butler
and the floodgates of planet hunting were now wide open.
- You know from no planets at all to the point
where we were discovering a new planet every month
or even sometimes every week.
And almost all of the planetary systems that we found
were very different from the Solar System.
Weren't even similar in the least bit.
- I remember asking at a meeting,
you know "How long do you think this will go on?"
And I think Michel Mayor said,
"Oh maybe, you know, another five or ten years,
and then the game is over."
Fortunately, the game just got a lot more exciting.
- [Natalie Batalha] After getting my PhD,
I became aware of this fellow
at NASA Ames Research Center, Bill Borucki.
- I would see him at all these meetings.
They were very small meetings back in the day.
And like he'd literally be by himself out having dinner,
so we would join him and chat about things
and he was very persistent.
- Bill walked around the halls and whenever the Ames managers
saw him coming they turned and walked the other way.
- Bill Borucki wrote a paper in the 1980s
that described the Transit Method.
When that planet passes in front of the star,
the starlight drops by a tiny, tiny amount.
And by measuring the brightness of the star minute by minute,
we can detect planets going in front of the star.
And we call that the Transit Method.
And detectors that could measure that precise drop in brightness
didn't exist yet.
- To be successful all one needed to do
was build a photometer
a thousand times better than anyone ever built one.
But I'd worked on the Apollo program,
I've worked on other programs.
So that's not really that scary.
You just need to get down to brass tacks, and
find out what's required, and build it.
There just is no way of finding small planets
in orbits like that of the earth,
unless you go into space. You must go into space.
- He kept getting shot down by the review panels
for various reasons, and each time he'd fix the reason
and go back a second time.
They basically said it's not gonna work.
Well, Bill Borucki didn't bother reading that report.
Or at least he did not take it to heart.
He kept on his crusade to show that
transit detection should work.
- [Sara] And he was able to demonstrate in the lab
that he could measure the precision required
to find earth-sized planets orbiting sun-like stars.
- Some people call it stubbornness,
but the point is I knew it would work.
- So he proposed, and re- proposed, and eventually
he conceived of a Discovery Class mission
that was later called Kepler.
- It was 25 years between the date of publication
and the date that Kepler actually launched.
- [TV Announcer] ...one, zero!
And liftoff for the Delta 2 rocket with Kepler...
on a search for planets in someway like our own.
- Kepler just delivered so much tremendously new things
we never even conceived of.
And the things that were on our wish list, Kepler found for us.
- This data was being displayed for the first time
on the computer monitors.
And there was the transit of that Jupiter-sized planet
and the data was like beads on a string.
- [James Fanson] Kepler's transformed our
understanding of exoplanets.
What Kepler was designed to do specifically
was to go after terrestrial or rocky planets
that are in closer orbits to stars.
We now know from the Kepler data, that planets
like the earth are in fact common in the galaxy.
And that's something
we fundamentally didn't know before Kepler.
- The first exoplanet was already diverse
and Kepler continued to find more and more planets
that didn't fit the norm...both in the size, in composition,
in distance from their star.
So when you think about how many stars there are in our galaxy,
a few hundred billion, and if each one has one or maybe more,
we're looking at a few hundred billion planets.
- [Natalie] To accomplish something great,
you have to have persistence.
- To succeed in exoplanets,
we have to be very ambitious and very bold.
- Kepler's impact was extreme,
certainly more than I ever ever imagined.
It's basically opened up an entire new era of astronomy.
- Now that we know that the galaxy is teaming with planets
we are ready to go to the next chapter
of planetary exploration.
- [Jason Kalirai] I truly believe that the 2020s
are shaping up to be a Golden Age
for observational astrophysics.
You know we have these amazing telescopes like TESS,
the Transiting Exoplanet Survey Satellite.
We have WFIRST, which is this Hubble-sized telescope
that can see a hundred times as much of the sky in each image.
We have the James Webb Space Telescope which is
the largest and most powerful telescope we've ever built.
You know the reason we can even dream about that and
create something like that is because of the success of
Spitzer and Hubble and the previous great observatories.
- I'm looking forward to space-based missions
where they're gonna have coronagraph technology
and maybe even star-shield technology in order to
image exoplanets by blocking out the light from stars.
- And we have the next generation large
30-meter class telescopes on the ground
which are gonna be coming online in the 2020s.
But the question that has me most excited
about the future of astronomy is to answer the question:
Are we alone in the universe?
- Finding evidence of life on an exoplanet,
finding an indication of a living world,
is within our reach.
- What is life?
Life is a process to transfer information
from one generation to another.
- Everybody is interested in the search for planets...
the search for places that remind us of home.
- [Scott] We're looking for some hint of our origins,
where we came from,
and exoplanets may very well provide that context.
- [Jill] There may be more habitable real estate out there
beyond our solar system than we once thought.
- [Jason] I think we're naturally curious to find out
if there are other conditions in the universe
that might be similar to our own.
And finding exoplanets around other stars
is the first important clue.
- [Debra] The search for planets is a search for life.
And even though we didn't really say that out loud,
that was always in the back of our minds.