Original subtitles

NARRATOR: For thousands of years,

humankind has attempted to make contact

with beings from beyond Earth.

GIORGIO A. TSOUKALOS: Even our ancestors

tried to send messages to the sky,

and we're still doing it today.

NARRATOR: Now, in the 21st century,

the search for extraterrestrial intelligence is ramping up

like never before.

TRAVIS TAYLOR: We might find life on another planet

in the next few years.

We might even find civilizations.

We're that close.

NARRATOR: And powerful new technologies

are allowing us to explore trillions of stars

all across the universe.

ROD PYLE: We've never had this many eyes,

this many lenses, this many radio dishes

looking for things at the same time.

NICK POPE: It's now only a matter of time

before science finds other earths,

and where there are other earths,

there'll be other life and other civilizations.

NARRATOR: There is a doorway

in the universe.

Beyond it is the promise of truth.

It demands we question everything

we have ever been taught.

The evidence is all around us.

The future is right before our eyes.

We are not alone.

We have never been alone.

French Guiana, South America.

December 25, 2021.

At the Guiana Space Center,

NASA launches the James Webb Space Telescope,

which is 100 times more powerful

than any telescope that's come before.

It represents an ambitious,

ten-billion-dollar effort by NASA

to see into the deepest parts of the universe.

To many, this highly sophisticated device

will finally enable scientists to answer an age-old question:

Are we alone in the universe?

The James Webb Telescope is our latest

and greatest space telescope,

uh, which has two basic missions.

One is to understand how stars and galaxies began,

and its other mission is to understand

whether there's life out there.

WILLIAM HENRY: The James Webb Telescope has the ability

to detect chemical signatures on planets

that suggest that life is, in fact,

present in those worlds.

TSOUKALOS: We can now look into space

with more clarity

than in all of our previous human history.

And with the new James Webb Telescope,

scientists are looking for extraterrestrial intelligence,

not just extraterrestrial, you know, biology.

The fact that we are investigating is

something very exciting because the search

for extraterrestrial intelligence

is the ultimate quest

of humanity to find out,

how did it all begin?

NARRATOR: With the launch of the James Webb Space Telescope,

astronomers are now able to examine thousands of planets

outside our own solar system,

often referred to as exoplanets.

And they are discovering more and more

that are located within the so-called Goldilocks zone.

There's something called the Goldilocks zone

where everything is just right.

You're just right from the Sun in terms of distance,

in terms of heat, in terms of ecology.

And that's where to find life.

TAYLOR: Now we're discovering

many tens of planets that seem to be

in the Goldilocks zone,

where it-it can have water

and an atmosphere that's warm enough for life.

MICHIO KAKU: We now realize there could be hundreds,

thousands of twins of the Earth in outer space.

This is big news 'cause it may mean that life could be

much more readily abundant in our galaxy

than we previously thought.

DAVID CHILDRESS: These new discoveries

by the Webb Telescope are pretty amazing.

They're finding these exoplanets that can hold life.

And now the search for extraterrestrials is on,

like, steroids.

We've got NASA involved in it.

We've got Chinese

and Japanese scientists who are looking at this.

We have a wide array of international players

who are searching for extraterrestrials.

NARRATOR: As far as ancient astronaut theorists are concerned,

our willingness to devote

so much time, energy and resources

towards the search for extraterrestrial intelligence

is firmly rooted in the distant past.

Since the very beginning of human civilization,

we have been looking for signs

of extraterrestrial intelligence.

You go back to the most ancient civilizations--

the Sumerians, the Babylonians, the Egyptians, the Mayans--

they all track the stars, they track the planets.

They built incredible monuments like the pyramids

that were in alignment with various star systems.

TSOUKALOS: You have multiple ancient megalithic structures

that are in the form of constellations,

mainly Sirius, Orion and Pleiades.

Why those three?

Well, we are suggesting

that that is where the extraterrestrials

who taught us a long time ago came from.

NARRATOR: Could it be that our earliest ancestors

had encounters with otherworldly beings?

And did they align

their most important structures with the stars

because they hoped this would be noticed

by the extraterrestrials who had visited Earth?

Ancient astronaut theorists suggest

that support for this notion can be found

by examining the theories

of a prominent 19th-century German scientist

named Carl Friedrich Gauss.

In 1820, Carl Friedrich Gauss was on the cutting edge

of our science and technology.

He's a mathematician and a physicist.

But he has one question:

Can we communicate with extraterrestrials?

He thought it was entirely possible.

Gauss proposed an incredible idea.

He said we need to go out into the Siberian tundra

and create a giant Pythagorean triangle that would be so big,

it could be seen from the Moon

and an extraterrestrial civilization would see it

and know that we were mathematically advanced

and make contact with us.

NARRATOR: While most scientists

regarded Gauss's idea as fanciful,

ancient astronaut theorists suggest there is evidence

that our ancestors used this exact method

to try to communicate with otherworldly beings.

In the 1930s,

more than a century after Gauss proposed his theory,

pilots flying over southern Peru reported seeing enormous shapes

carved into the earth--

the Nazca Lines.

TSOUKALOS: The Nazca Lines are the animals,

the hummingbird, the monkey,

all these different things from the animal kingdom.

And straight lines,

some of which go up to 15 miles.

The Nazca Lines clearly were created by humans

to signal somebody up there, not on the ground.

Why? Well, according to the ancient astronaut theory,

the local population was visited by extraterrestrials,

but at some point, they left.

And so the local population wanted them to come back.

And that is why the Nazca Lines were created on a bigger scale.

The Nazca Lines are a giant signal

to someone up in the sky.

NARRATOR: Is it possible that ancient people

created the Nazca Lines

to attract the attention of intelligent beings,

like Gauss proposed in 1820?

Today, scientists believe

that we will soon have the technology

to see surface features on distant planets ourselves,

and the James Webb Telescope is already allowing astronomers

to observe the universe in greater detail

than ever before.

Our current technology isn't such that we can

truly image Earth-sized planets around other stars.

But we can look at what elements

and what chemical compounds are in that planet's atmosphere.

CHRISSY NEWTON: The James Webb Telescope

has found multiple different exoplanets

that have markers of life, that have markers of carbon.

We see that some of these exoplanets have water in them,

and water is a major marker for life.

So it's exciting to see what the James Webb Telescope is doing

and what else it will find.

NARRATOR: Could it be that in searching

for extraterrestrial intelligence,

we are carrying on the work of our earliest ancestors,

as ancient astronaut theorists suggest?

And might new technology

like the James Webb Space Telescope

help us to finally succeed in achieving this goal?

Many experts believe it will

and suggest there is evidence

that Earth has already received communication

from an alien race.

NARRATOR: Colorado Springs.

July 1899.

Famed scientist and inventor Nikola Tesla

is conducting radio experiments at his laboratory

when he receives an unusual repeating transmission

from an unknown source.

Nikola Tesla believed that

extraterrestrial communication was possible.

And this signal was exactly the type of signal

he would've expected to have seen

from an extraterrestrial civilization

if they were trying to make contact.

And Tesla himself believed

he had received radio signals from Mars.

NARRATOR: More than 5,000 miles away,

Italian radio pioneer Guglielmo Marconi

observed similar seemingly extraterrestrial transmissions.

Marconi was the first to really

broadcast radio across long distances.

And he, of course, was also listening.

And he also thought that he might have heard

some radio signals from-from the planet Mars.

HENRY: Nikola Tesla and Marconi were on the cutting edge

of this new frontier of discovery,

believing in their hearts, in their minds

that radio waves would lead to our connection

with an extraterrestrial civilization.

NARRATOR: Is it possible that the mysterious transmissions

detected by both Nikola Tesla and Guglielmo Marconi

came from an extraterrestrial intelligence?

While the answer will likely never be known,

the observations of these early radio pioneers

had a major impact on humanity's search for alien life.

Marconi and Tesla

kind of got the ball rolling when it comes to

trying to find the aliens by eavesdropping on radio signals.

And it turns out radio waves would be a great way

to communicate over very long distances

from one star system to another.

They're better even than ordinary light,

because there are dusty, dark clouds in the universe

and they can... they can block the light.

So the point about radio waves

is that they would go right through the dust and gas

that hangs between the stars.

NARRATOR: Tesla and Marconi may not have found definitive evidence

of alien intelligence,

but they were foundational in establishing the primary means

by which scientists search

for extraterrestrial civilizations today.

This effort is led by the SETI Institute,

established in 1984.

SETI is the Search for Extraterrestrial Intelligence.

And a lot of it has been done by the SETI Institute

based in California.

It is primarily the use of radio telescopes

to listen for a signal from another civilization.

SETH SHOSTAK: The SETI Institute,

its flagship program is to use big antennas,

point them in the direction of other nearby star systems

and, you know, tune over the radio dial to see

if there's any transmission coming from those planets.

POPE: The thinking is that we have been a detectable civilization

for years through our television and radio broadcasts,

and almost any conceivable advanced civilization

will be using that technology

or will have used it in the past--

maybe they've gone on to more advanced things now--

but that will be detectable.

And people look for a beacon, maybe,

to just draw our attention to the fact

that there's life out there.

But also a message.

Maybe there's scientific and technical knowledge encoded

in a signal being sent to us.

Well, if we don't listen, we'll never get it.

NEWTON: The work of the SETI Institute is so important

for the fact that they are a pioneer.

They're a pioneer in the world of academia,

in the world of science

and have pushed the boundaries, I would say,

in the understanding and the acceptance

of looking into extraterrestrials.

NARRATOR: But not all scientists were content to merely listen

for alien communication.

A decade before the establishment

of the SETI Institute,

one of its founders, famed astronomer Carl Sagan,

was part of an effort to send a message out into the cosmos.

♪ ♪

Arecibo Observatory, Puerto Rico.

November 16, 1974.

Scientists, dignitaries

and other public officials gather to watch

as astronomers send out

the first official radio communication

directed to extraterrestrials

using the largest, most powerful telescope in the world.

SHOSTAK: The message was just a series of, you know,

dots and dashes, if you will.

But you could order them into a-a matrix

and actually get a picture

as a way of sending a greeting card, if you will, from Earth.

NARRATOR: Designed by renowned scientists like Carl Sagan and Frank Drake,

the Arecibo message contains binary-encoded information,

including the numbers one through ten,

an image of human DNA,

a human figure

and a graphic of the solar system,

highlighting the position of Earth.

POPE: This was a calling card from planet Earth.

It was really reaching out across the galaxy

and saying, "We're here."

Now, some scientists condemned it.

And, in fact, SETI has been very controversial

when it moves into active-- what's called METI--

"messaging to extraterrestrial intelligence."

Some people have said it's like a suicide note to the universe,

because if there's a super predator species out there,

you were saying, "Come and get us."

Now, SETI scientists say, "Well, it's too late.

"We've been a detectable civilization for decades

because of our radio and television broadcasts."

But it's still controversial.

NARRATOR: In August 2001,

almost three decades after the Arecibo message was sent,

there was an extraordinary development.

Workers at the Chilbolton Observatory

in Hampshire, England,

discovered a mysterious crop circle in a nearby field

that was an almost exact replica of the Arecibo message.

It's actually called sometimes the Arecibo reply,

because it-it's essentially very similar

to the Arecibo message but with some subtle changes.

For example, the DNA swaps out carbon for silicon.

And also, there's a-a representation of a figure,

but it's not a human.

Looks like an alien.

Instantly, the astronomers proclaimed this a hoax.

And as people started to investigate this,

they realized that maybe it was possible

that it came from extraterrestrials.

One reason why was that the message was so perfect.

How likely is it that some crop circle hoaxer

could have duplicated that message in a crop circle?

Crop circles are a very important potential way

that an extraterrestrial intelligence could use

to communicate with us.

They're very public,

and they have caught the curiosity of humanity.

NARRATOR: Was the so-called Arecibo reply a message sent to Earth

by an extraterrestrial civilization?

While its origin continues to be debated,

some scientists suggest

that the best evidence of intelligent life

that the best evidence of intelligent life

can be found by simply looking deep into space

for what aliens may have built

in the stars.

NARRATOR: At the Murchison Radio-astronomy Observatory,

one of the world's most powerful telescopes detects a signal

that catches the attention of scientists

from multiple institutions.

They discover interstellar radio waves

that are reaching Earth every 22 minutes.

Even stranger,

the signals have been sent, like clockwork,

for more than 30 years.

HENRY: Astronomers in Australia made an amazing discovery--

a timed pulse, a radio wave pulse

that went completely undetected.

This was a milestone, a benchmark

in our search for extraterrestrial intelligence.

SHOSTAK: The thought is, it turns on and off every 20 minutes--

a little too regular to be due to nature.

And, uh, you know,

when you find something unexpected,

of course you're excited.

PYLE: Now, normally when you see a repeating signal like that,

you think of either a pulsar,

which is a rotating star that's sending out a radio burst

on a regular schedule,

or a magnetar,

which is a similar kind of star that is...

has a very intense magnetic field that's rotating.

And so you get spikes of a signal from that magnetic field.

The problem is, this signal doesn't match either of those.

TAYLOR: We don't know what this signal is,

but we do know that it seems interesting

and possibly artificial,

which means it was broadcast by someone.

We may find that there's a, uh,

natural phenomena that explains it.

We may not.

POPE: Some people have speculated

that this could mean that extraterrestrials

have been signaling to us

for a very long time.

Now, there's still a lot that we don't know about this,

but there's something very odd about it.

CHILDRESS: This is the kind of thing that we've been searching for

for decades.

It's tremendously important, this discovery.

NARRATOR: Is it possible

that the strange radio pulses detected in 2023

are signals being sent out by alien life-forms?

Perhaps further clues can be found

by examining another discovery

that some scientists believe

is evidence of an extraterrestrial civilization.

Astronomer Tabetha Boyajian publishes a paper

in the Monthly Notices of the Royal Astronomical Society

that captures the attention of the scientific world.

Using data gathered by NASA's Kepler space telescope,

Boyajian documented strange behavior in a distant star.

GIBOR BASRI: The Kepler telescope was searching for exoplanets

by waiting for them to cross in front of their star

and block a little bit of light.

Well, she found a star

where the amount of light that was blocked kept changing.

It was much more light than a planet could block.

So Tabby's Star was-was kind of a...

a surprising discovery at the time.

KAKU: Tabby's Star suddenly diminished in terms of its intensity,

uh, by quite a bit, and then flared up again

and has been doing this for years.

What could cause that?

What is big enough

to diminish starlight by that much?

It must be huge.

NARRATOR: The bizarre dimming led some astronomers to consider

a profound possibility:

that the dimming was caused

by an extraterrestrial megastructure

known as a Dyson sphere.

This hypothetical technology

was first proposed by Princeton physicist Freeman Dyson

in a 1960 Science Magazine article.

TAYLOR: One of the Manhattan Project scientists,

Freeman Dyson, had the idea that a really advanced civilization

could build a sphere around their star

at about an Earth orbit distance from that star.

And it could capture all of the energy

from that star on the surface of this sphere.

SHOSTAK: This idea that advanced societies

will build stuff that they put into orbit

around the star, their sun,

you know, that makes perfect sense.

There's a lot of reasons why you might want to do that.

Maybe just collecting solar energy. I mean, who knows?

But if they built anything like that,

then we would see a star that gets dimmer,

then it gets brighter, it gets dimmer.

NARRATOR: Is it possible that Tabetha Boyajian discovered

an enormous alien spacecraft?

One so big it could block out the light of a star?

It's an idea that seems ripped

from the pages of science fiction.

But not only do NASA scientists

believe such structures could exist,

they are actively searching for them.

The effort that I lead at SETI

is a search for what we call alien megastructures.

These are large panel-like objects

that may have been put in orbit around other stars

by civilizations, um, well beyond Earth.

It would immediately indicate to us

that there are beings out there in the universe

that are more advanced than us.

Alien megastructures should not be that hard to find.

I mean, if they're out there, there are various telltale signs

that a big enough telescope, especially a space telescope,

should be able to spot

if we have an idea what we're looking for.

The problem is going through

hundreds and thousands of hours of data.

So, Ann Marie Cody started a project

specifically targeting alien megastructures

with artificial intelligence, A.I.

TSOUKALOS: The fact that Dr. Cody is getting funding

to investigate this is unheard of.

And the fact that it is happening means

that a paradigm shift has happened.

CODY: We need to know who is out there possibly

so that we can learn more about ourselves

and what sort of course humanity is going to take.

Right now, we are dealing with

unprecedented problems on Earth.

If we found beings out there that were

more intelligent than us,

they may offer useful information

if we were ever to learn from them.

NARRATOR: Might strange radio pulses

and the mysterious dimming of stars

be evidence that we are not alone in the universe?

According to some scientists,

the best evidence of alien technology

the best evidence of alien technology

can be found closer to home,

right here on Earth.

NARRATOR: Ever since the first radio telescope

was invented in the 1930s,

astronomers have listened to the heavens

for signals from extraterrestrial beings.

But in 2021,

Harvard professor Avi Loeb breaks with tradition

and sets out to find alien life

not by scanning for radio waves

but by looking for physical evidence.

He calls it the Galileo Project.

KAKU: Professor Loeb says, why not monitor

meteors and things in outer space?

Perhaps one of them is remnants of an advanced civilization.

For example, if an advanced civilization is like us,

they would leave Coke bottles everywhere,

and why not search for them?

The previous paradigm was: sit, wait, open your telescope,

open your computer and cross your fingers.

That's the way science is usually done in astronomy.

Now he's saying, "Why not reach out?"

LOEB: All we need to do is search around

and we might find objects

that were sent by civilizations.

Those civilizations, they could have launched probes

to interstellar space that would have populated

the entire Milky Way galaxy by now,

and the only question is: Do we live in such a reality?

NARRATOR: According to Dr. Loeb,

if alien civilizations do exist...

...their spacecraft might appear to us

as something as simple as a meteor.

POPE: The Galileo Project involves the idea that

alien probes may have visited our solar system

and possibly crashed on

the Earth's surface or the oceans in the past.

NARRATOR: If extraterrestrial craft have landed on Earth,

is it possible that the Galileo Project could find them?

While the idea of a Harvard scientist

searching for a crashed UFO

struck many in the scientific community as laughable,

in 2023, Dr. Loeb shocked the world

when he announced he found one.

June 2023.

100 miles north of Papua New Guinea.

Dr. Loeb and members of the Galileo Project

are combing the Pacific Ocean in search of a meteor

that exploded over the region ten years earlier.

LOEB: I came across a meteor catalogue

that the government compiled

using its missile warning system.

The meteor, uh, burned up

about 100 miles off the coast of Papua New Guinea,

and it released a few percent of the energy

of the Hiroshima bomb when it exploded.

The government released data of the explosion,

and from that, we inferred that the object

has material strength that is very unusual.

It's made of some alloy that is much tougher

than iron meteorites,

and that raises the possibility

that it may have been a spacecraft.

NARRATOR: For two weeks, Dr. Loeb and a team of scientists

drag a large magnetic sled along the ocean floor.

And then they make what could be an extraordinary find.

PYLE: Loeb did find a number of beads,

little spherules, not much bigger than a BB,

that they were able to dredge up.

Upon first glance, they look kind of exotic.

They have little swirls in them.

They're almost perfectly round.

HENRY: The spheres are sub-millimeter size.

When they get back to the lab and they put these spheres

underneath a microscope,

they describe them as beautiful metallic marbles.

This suggests, in a preliminary way,

that we're dealing with perhaps an extraterrestrial technology,

something that was not made by nature.

PYLE: Just finding little metal beads

isn't proof that they're ball bearings

for an alien spaceship or something,

but they could be, and that's the exciting part.

You can't prove it yet, but you can't disprove it, either.

NARRATOR: Initial testing showed that some of the spherules

had an unusually high concentration of beryllium,

lanthanum and uranium in a composition

that is unlike anything found in our solar system.

CAROLINE WHITEHILL: That composition

does not exist in any known

mineral or rock that we know of,

which would imply something about the conditions

under which it was formed-- the temperatures, the pressures.

And when you combine that with the spheroidal shape,

it does speak to his hypothesis

that they were manufactured extraterrestrially.

NARRATOR: Could the strange spherules found on the ocean floor

really be of alien origin?

While more tests are underway,

Dr. Loeb continues to recruit experts to the Galileo Project

like renowned UFO researcher Jacques Vallée,

retired intelligence officer Christopher Mellon

and former British Ministry of Defence UFO investigator

Nick Pope.

POPE: Now, I'm not a scientist,

but I'm one of a number of people who are involved

and actually part of Galileo Project

as a research affiliate.

So, people like myself, with government backgrounds,

who can perhaps help the science team with this,

we've come on board, and-and it's fascinating work.

And think about this-- Harvard alien hunter?

This represents an enormous step forward in humanity's quest

for extraterrestrial intelligence because

we're-we're seeing signs and signposts of academic acceptance

of the reality that we are not alone.

Just the fact that Harvard University

has the Galileo Project,

this shows that we're in a brand-new era

where prestigious universities

and scientists associated with them

are trying to find extraterrestrial life.

NARRATOR: Will the Galileo Project find irrefutable proof

that we are not alone in the universe?

Only time will tell.

But while researchers like Avi Loeb

are making great strides in the search

for extraterrestrial intelligence,

some believe even more exciting evidence

is being discovered by NASA scientists,

is being discovered by NASA scientists,

who recently found strong indications

of a planet inhabited by alien beings.

NARRATOR: A team of astrobiologists

at Washington State University

complete an analysis of more than 4,500 exoplanets.

After combing through the data,

they are surprised to find 24 planets

that fit the classification of "superhabitable."

TAYLOR: Very recently, we have discovered many planets

that might be better for life than Earth is.

Earth is still in an ice age right now.

We have polar caps on both sides of the planet.

So, these planets might be even more habitable

or-or better for life to spring up on than here on Earth.

PYLE: For the most part, they're larger than Earth.

They tend to be older.

The longer you give life to evolve,

the more likely you're gonna see advanced life-forms there.

NARRATOR: The first exoplanets were discovered in the 1990s,

and since then, scientists have been astounded

by the number of potentially habitable planets

they have found throughout the universe.

Before 1995, we didn't know whether

there were other planets out there.

Today, we know that the majority of stars

have planets orbiting them.

And, you know, one in ten of those

have a planet that's at the right distance

from that star so that the temperatures,

you know, are agreeable for life.

And there might be liquid water on the surface

and that sort of thing.

So what we're finding is that the Earth

may not be unique, that there are other planets

that also have things like atmospheres and oceans.

And if you're looking for E.T., well, it's good to find

that there are other locales that might at least have life.

NARRATOR: It's only recently,

with the launch of the James Webb Telescope,

that scientists have been able

to study nearby planets for signs of life.

The James Webb Telescope is now powerful enough

to pick out some of those planets

and actually measure their atmospheric composition.

And then we'll-we'll be a step closer

to-to actually knowing whether there's life out there.

HENRY: The James Webb Telescope has the ability

to peer into the infrared level,

where it can detect heat signatures

and also chemicals on exoplanets that

previously have gone undetected.

Early results are astonishing.

It's already made major discoveries

on two planets that are suggestive that life

might actually be present on these planets.

PYLE: The Webb allows you to see things that tell you

whether or not there might be life there.

And more excitingly, might tell you

that there's been technology there.

When you start seeing radioactive isotopes,

now you've got a better idea that there might be technology.

It's probably high technology,

and that's what we're looking for.

NARRATOR: In September 2023,

scientists found what many consider to be

the best evidence yet that life is not unique to planet Earth.

In the atmosphere of a planet

124 light-years from Earth called K2-18 b,

the James Webb Telescope detected the presence

of a molecule called dimethyl sulfide.

TAYLOR: Dimethyl sulfide is created through

organic processes only, as far as we know.

Meaning some living creature,

during its life cycle, secretes or excretes this material.

KAKU: The very fact that that chemical is there

indicates there's a high probability

that a life-form was responsible for creating it.

In other words, this could be the first sign

of life in outer space.

NARRATOR: Is it possible that NASA has finally discovered

life on an alien planet?

While scientists need more evidence

before they can be certain, the presence of dimethyl sulfide

suggests this is a strong possibility.

If proven true, the next question is:

Are these life-forms intelligent?

Could it be that planet K2-18 b is home

to an extraterrestrial civilization?

TSOUKALOS: The fact that they've discovered DMS on a planet out there,

and if this can be corroborated, well, there you go.

And now the next step will be, we now know E.T. exists.

Number two will be, not only are we not alone,

but they've been here.

TAYLOR: We are right on the edge

with our modern-day technology that we might find

life on another planet in the next few years.

We might even find civilizations that have

sprung up on these planets in the next few years.

We're that close. Our technology is there.

NARRATOR: Could advances in human technology,

like the James Webb Space Telescope,

be the key to finally discovering life

and maybe even intelligent life beyond Earth?

Some scientists predict our search will end

with direct contact from advanced alien civilizations

not at some distant point in the future

but any day now.

NARRATOR: Astronomers at the University of Toronto

announce that they are using artificial intelligence

to search for evidence of extraterrestrial technology

from 820 nearby stars...

...and have detected some highly intriguing signals.

HENRY: Astronomers have used a machine-learning algorithm

to sift through 480 hours of tapes,

and they found eight signals

that they believe potentially could be a techno signature.

A signal suggesting an advanced extraterrestrial civilization

might even be inhabiting these planets.

NARRATOR: While more research needs to be conducted

to determine exactly what is producing

these mysterious signals,

many experts believe the use of A.I.

will astronomically accelerate

the search for extraterrestrial intelligence.

CODY: Artificial intelligence is playing

an increasingly important role

in the search for extraterrestrial technology

and intelligence,

simply because there is so much data

coming through astronomers' telescopes nowadays

that we need help with our needle-in-the-haystack searches

to find the most unusually behaving

stars and signals embedded in that starlight.

BASRI: What A.I. is particularly good at

is it's really good at recognizing patterns,

and patterns are really what we're looking for in SETI.

So, we want to find patterns that we don't think

nature would produce.

Feeding all the radio signals that we...

that we receive from the stars

into the right A.I. system would help enormously

in identifying patterns that humans might not find.

NARRATOR: While scientists are excited

by the prospect of humankind's first encounter

with an advanced alien civilization

in the near future,

ancient astronaut theorists view this possibility

through a different lens.

To them, such an event would not be first contact

but a reunion.

TSOUKALOS: Does official contact mean

a signal that has been received through SETI?

Or will it be, you know,

a validation of the ancient astronaut theory?

That, you know, hey, not only are we not alone in the universe

but they've visited in the past and they've been here.

In my opinion,

the E.T.'s are here, they're observing us,

and SETI is one way

with which to prepare the masses.

POPE: It may be at the moment that civilizations

are aware of us, visiting us, but don't make open contact.

But all that secrecy will end the day we find out about them,

because the cat will be out of the bag

and we'll have open first contact.

Up close and personal interaction between

extraterrestrials and humanity.

And that will tell us something interesting

about the extraterrestrials, but it may also tell us

something rather interesting about ourselves.

MAN: Look at it fly!

TAYLOR: It's very likely that we're right at the edge

of the next era for humanity

when we realize we're not alone in the universe.

Extraterrestrials make contact with us,

that's gonna change humanity more than you can imagine.

HENRY: We need protocols in place.

We need to begin to prepare

human civilization for this reality

and the transformation that will result

once contact is established.

CHILDRESS: I think planet Earth will be ready for it

and we will hopefully rejoice

in the fact that we are in contact with extraterrestrials

and that we are not alone in the universe.

NARRATOR: Now that the search for extraterrestrial intelligence

has been taken up by top scientists

and academics all over the world,

are we on the verge of making contact

with an alien race?

Could powerful new technologies detect life

and even civilizations on other planets?

Or might we even uncover an otherworldly presence

right here on Earth?

Perhaps one day soon,

we will learn the truth that we have been seeking

since the beginning of humankind.

We are not alone.

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