Original subtitles

NARRATOR: Space ships over Los Angeles...

Body snatchers controlling our minds...

E.T.'s making contact.

These and other alien-based scenarios

have been the plot lines of countless

science-fiction movies and television shows.

But what if extraterrestrial beings

came to Earth tomorrow?

Would they signal the birth

of a new age of peace and prosperity,

or trigger a war of the worlds?

NICK POPE: The day that it's announced we're not alone

is the day that this planet changes forever.

BILL BIRNES: The very structures of government

and the very structures of religion will crumble.

SARA SEAGER: Everybody wants to meet an alien.

But we have to start small.

We have to learn how to walk before we can run.

NARRATOR: Millions of people around the world

believe we have been visited in the past

by extraterrestrial beings.

What if it were true?

Did ancient aliens really help to shape our history?

And if so, what might happen when they return?

NARRATOR: Throughout human history,

man has gazed up at the stars in awe and with wonder.

Our ancient ancestors charted their movements,

identified constellations

and marked time by creating celestial-based calendars.

The stars also became the source of countless myths and legends.

Many of these describe visitors

coming down to Earth from somewhere out there.

Others speak of entire civilizations

existing out in the cosmos.

MICHAEL CREMO: The ancient Sanskrit writings of India

tell us, for example,

there are 400,000 humanlike species

scattered throughout the cosmos

in different planets, different solar systems,

even different dimensions.

NARRATOR: But where are these alien beings?

Did they come to Earth in the past,

as the ancient astronaut theory suggests, and then leave?

If so, will they ever come back?

Today, scientists around the world

have stopped waiting around and are taking steps

to find intelligent extraterrestrial life.

Will technology finally be able to prove

what our ancient ancestors believed thousands of years ago?

In 1960, astronomer and physicist Frank Drake

set up an unusual telescope in the hills of West Virginia.

The strange device was made

from surplus World War II radar equipment.

But rather than containing a traditional optical lens,

it housed a directional radio antenna.

PAUL DAVIES: A few simple calculations showed

that radio telescopes have the power to transmit

and receive across literally interstellar distances.

We're talking many light-years.

So Frank Drake turned a radio telescope

on a couple of nearby stars and tuned in

to see if he could pick up a message from the aliens.

So this was a sort of crazy thing to do.

NARRATOR: Drake failed to pick up any sounds that day,

but the science of radio astronomy was born.

If we couldn't see aliens in space,

maybe we could hear them.

MICHAEL DENNIN: The things we've focused on in the past

for searching for extraterrestrial life

is really passively trying to discover signals

on the basis that if they were technologically advanced,

they would have some form of electricity like we do,

and all electricity generates radiation.

And it sends out the signals, and hopefully we detect it.

NARRATOR: In 1961, Frank Drake and a group of astronomers,

physicists and biologists

formed a privately funded organization called SETI:

the Search for Extra-Terrestrial Intelligence.

Their goal was to focus massive radio telescopes

towards space and listen.

Drake estimated the probability

that intelligent life existed out in the universe

in a formula that became known as the Drake equation.

SEAGER: The Drake equation is like a bridge

between scientists and non-scientists,

because it explains what you would want to know

to give a number about how common alien life could be.

JENNIFER HELDMANN: There are multiple factors

within the Drake equation.

Like the fraction of stars that could have planets;

and the fraction of those planets that could be habitable;

and the fraction of those that might have liquid water;

and how many could have evolved intelligent life?

And then one important factor

is the lifetime of those civilizations,

and that is a big unknown.

We only know of one-- that's ourselves.

And how long are we going to be around?

That's to be determined.

NARRATOR: Using his equation, Drake estimated

that over 100 million advanced civilizations

could exist in just the Milky Way galaxy.

BIRNES: SETI presupposes

that if you’ve got an alien civilization

capable of traveling that's developed electronics,

they have a fingerprint.

That fingerprint is a repetitive signal.

A repetitive signal will tell them

that it's not just noise, junk frequencies out there,

but a real attempt at communicating,

maybe not with us, but with each other.

NARRATOR: On August 15, 1977,

astronomer Dr. Jerry Ehman

was working on a SETI project at Ohio State University

when he recorded an intermittent signal

coming from the direction of the constellation Sagittarius.

The signal lasted 72 seconds before being lost.

Ehman believed that it was of extraterrestrial origin.

But despite repeated searches

and increasingly larger telescopes,

the signal has never again been detected.

But what if SETI intercepts a transmission from another world?

What would happen next?

According to SETI's Post-Detection Protocols,

once an extraterrestrial radio signal is confirmed,

news of the event should be kept secret

until the authorities have been notified.

The government will then decide

whether or not to try and make contact.

DAVIES: I think all bets are off.

Because here's this message.

It could contain enormously important information

that would transform our society and maybe destabilize it.

What is it going to mean for the future of our civilization?

These are momentous questions.

NARRATOR: Today, SETI continues to scan

the vicinities of nearby stars

for artificially produced signals

using several of the world's largest telescopes.

In the next several years,

when it becomes fully operational,

SETI's new Allen Telescope Array

will allow for the reconnaissance

of up to a million stars.

SEAGER: SETI has to search a huge, huge area.

They'll tell you that now,

they have searched the equivalent of, like,

a glass of water compared to the entire ocean on Earth.

They have a long way to go.

NARRATOR: While SETI listens passively

to signals from outer space,

NASA has attempted to contact alien life directly,

through messages sent aboard its space probes.

DENNIN: It's a long shot,

but there's no reason, in my mind,

not to expect that life evolved elsewhere.

What's harder to predict, or try and understand,

is how likely is it that it happened close enough

that there'd be someone we could actually communicate with.

NARRATOR: In 1972, NASA agreed to attach small plaques

onto the outside of its twin Pioneer space probes,

the first human-built objects

destined to leave our solar system.

NASA contacted Cornell University professor,

Dr. Carl Sagan, to craft the message.

DENNIN: Carl Sagan was one of the most active astronomers

in the search for life outside our planet.

He was a very prominent scientist,

he was an excellent astronomer, and he really did a lot

to help us understand how we might contact other life

or detect life elsewhere in the universe.

NARRATOR: Sagan, along with SETI founder Frank Drake,

designed a gold-anodized aluminum plaque,

measuring roughly six by nine inches,

that contained a collection of symbolic images

representing humans and Earth.

ALBERT HARRISON: The man and the woman were nude,

and the gentleman was holding one arm up like this

in what was intended to be

a sign of, uh... a sign of greeting.

NARRATOR: A schematic design of the solar system

was also shown, with the planned trajectory

of the Pioneer spacecraft marked on it,

and a diagram of 14 pulsar stars around the sun

made a chart that might help someone work out

where the craft originated.

DENNIN: We tried to give them an idea of where we're located--

and that's an interesting problem, is to figure out

how you would tell someone where you're located in space,

'cause you don't know where they're going to find it.

And it was all in a very stylistic design,

but in an attempt to hopefully communicate

at least some of these ideas.

NARRATOR: Five years later, in 1977,

Dr. Sagan got a second chance

at designing an interstellar message

when NASA agreed to attach another one

to the Voyager space probes.

This time, Sagan created a record album

made of gold-plated copper,

along with a series of basic instructions

in how to make it work.

Sagan estimated that the metallic disc

could survive in space for at least a billion years.

DENNIN: One of the challenges with technology

is trying to figure out one that can do what you want--

so here you want to encode audio,

and even some video images,

but do it in a way that almost any other

technologically advanced society could figure out.

And the advantage of a record player is,

it's both mechanical and electrical.

The grooves are obvious.

And so, they actually put on the cover

instructions on how to play it.

NARRATOR: The recording included a wide variety of sounds--

a babys cry...

wind...

surf and rain, animal noises,

as well as classical and cultural music

from around the world.

One interesting song selection

was Chuck Berry's rock and roll hit, "Johnny B. Goode."

DENNIN: Music is a good choice

'cause almost anything vibrates and makes sound.

So I would have bet that almost any culture would develop music.

I believe it's Bach who gets the most time on the record.

I don't know why they picked that, to be honest,

but he is one of the more mathematical composers,

and that might have been one of the reasons,

because math is a more universal language.

NARRATOR: Sagan also included a wide array of photographs

of well-known man-made structures

and greetings in 55 different languages.

GIORGIO TSOUKALOS: I think the most important one

is the Sumerian language.

Now, why would they include Sumerian on that record?

Well, according to the ancient alien theory,

ancient Sumeria is the first place

where we made contact with an extraterrestrial entity.

DENNIN: At this point,

we obviously haven't learned anything yet

about extraterrestrial life,

because we haven't been contacted back.

But I think, for our own purposes,

any time you try and go and figure out

how you want to communicate something,

it pushes your boundaries and understanding

of communication itself.

SEAGER: We all want to find aliens.

Whether it's the planetary scientists

looking for signs of life on another distant planet.

Whether it's the ancient alien proponents

who want to find signs of life

of aliens who visited in the past.

And whether it's people today who want to have experiences

with UFOs and aliens that have visited them recently.

All of us are trying to do the same thing.

NARRATOR: While the search

for extraterrestrial beings continues,

a new space-based telescope

is hunting for planets that may contain life.

Are there other Earths out there?

And if so, how will we find them?

MAN: Ignition.

Lift off. Lift off...

NARRATOR: On March 6, 2009,

NASA launched a Delta II rocket into space.

On board was a new telescope named in honor

of German astronomer, Johannes Kepler.

The space-based telescope was designed specifically

to discover the existence of earthlike planets

located outside our own solar system.

The Kepler search is focused on a specific section

of the Milky Way known as Orion's Spur.

Kepler's job is to answer the question,

how common are other Earths?

And to do this, Kepler is looking at one part of the sky

for three and a half years.

Imagine, like, keeping your eyes open

and staring at just one part of the sky.

HELDMANN: And what they're doing is they're looking at stars.

And then, as a planet goes around that star,

when the planet gets in front of the star, the starlight dims,

just a little bit, from our vantage point,

because it's being blocked by the planet.

And so, you look for that dimming of those stars.

And then that's how you're able to detect these planets.

NARRATOR: So far, the Kepler telescope

has confirmed the existence of five planets

outside our own solar system.

NASA officials expect to find

several hundred more exoplanets like these

before their mission is completed.

Once a planet has been located,

scientists must then determine if it might contain water.

HELDMANN: We know from Earth

that all life on Earth requires liquid water.

(croaking)

So that is the approach that we've been taking

for looking for life elsewhere in the universe--

follow the water.

And so, that is the step one.

(crackling)

(bubbling)

DAVIES: On Earth, wherever we find liquid water, we find life.

And it's true.

Life on Earth can exist

under an extraordinary range of conditions.

There are extreme organisms

that live in the scalding effluent

coming out of the Earth's crust deep beneath the ocean.

There are other remarkable organisms

living in the waste pools of nuclear reactors

of extreme radiation environments and so on.

But the one thing that seems to be absolutely necessary

for life as we know it is liquid water.

NARRATOR: To determine if a planet

contains water and possibly life,

scientists use special telescopes

to analyze its atmosphere.

SEAGER: We look at the light coming from the planet.

And we split that light up, like a rainbow.

Now, if you look at a rainbow in the sky,

and you look really, really carefully,

you will see some dark lines.

You'll see some colors missing from the rainbow.

And those colors are missing

because of absorption by gases in Earth's atmosphere.

So effectively, we're getting a rainbow from another planet,

and we're looking for dark lines

that tell us what kind of gases are in the atmosphere.

NARRATOR: To better understand how life affects its atmosphere,

NASA scientists study microbial mats

at California's Moss Landing Wildlife Area.

BRAD BEBOUT: Microbial mats are important to NASA

for a whole bunch of reasons.

The organisms that are in microbial mats

have been on Earth just about longer

than any other kind of organism.

They make a number of things

which we call biomarkers, which are important

in our search for life on other planets.

So, there are textural biomarkers,

so when you pull up a piece of microbial mat

and look at the surface-- what does that look like?

One of the things that we're doing with these microbial mats

is we're measuring the fluxes of methane.

Methane is a gas that's produced by certain kinds of organisms

that use the organic matter that's in these mats.

And when that methane goes into our atmosphere,

it can be detected by other missions,

such as Terrestrial Planet Finder,

is one of NASA's concept missions for looking for gases

that are produced by life on exoplanets.

DENNIN: We can look for the signature

of oxygen or water on a planet, and at least that

would give us an idea of life-forms like ourselves--

ones that are carbon-based,

and use oxygen and carbon dioxide cycles.

Our atmosphere is not stable without living organisms.

It would have evaporated away by now.

And so, if you're looking out in space,

and you detect around a star

a signature of the chemicals that we know exist for life,

that's very strong evidence that life is there.

Now, it doesn't help you know if it's intelligent life,

but it does give you an evidence for life.

NARRATOR: With a universe literally full of possibilities,

planet hunters focus their search

on an area they call a Goldilocks Zone.

SEAGER: The Goldilocks Zone for planets

is the place where a planet is not too hot, not too cold,

but just the right temperature for life.

Right now, we know of no planets like Earth in a Goldilocks Zone.

One planet comes close.

It's called Gliese 581 d.

But we're not entirely sure if that planet

is really in the Goldilocks Zone or not.

DAVIES: In recent years, it's been recognized

that there's more than one Goldilocks Zone.

For example, there could be life inside icy planetesimals--

these, like, small planets or large moons.

The moon of Jupiter, Europa, is a very good example.

Europa is liquid beneath an ice cap.

It's liquid underneath because of tidal heating

and friction going on inside the planet.

So it could be that there is life--

microbial, probably, only--

deep down under the ice on Europa.

HELDMANN: It's a very challenging question--

if there is life elsewhere in our solar system.

You have so many components that have to come together.

We have to have an understanding of the science.

We have to ask the right questions.

I wish I had a tricorder that I could just go

and, like, point, and it would say "life"

or "no life," right? But we don't have that.

So, we have to be smart, and we have to be clever,

and we have to develop instruments

that can actually address the questions

we're trying to answer.

SEAGER: It's inevitable.

There are so many planets out there, it's inevitable

that we'll find one in the Goldilocks Zone any day.

NARRATOR: But while the Kepler telescope

has only just begun scanning the horizon,

NASA is already planning the next step

in its search for extraterrestrial life:

the 2014 launch of the James Webb Space Telescope.

People always ask me,

"Do you expect to find an Earth in your lifetime?"

And I say, "Yes, absolutely."

DAVIES: When I was a student,

there was almost nobody prepared to argue that way.

The feeling back in the '60s and '70s

was that even if there were other earthlike planets,

life is such an improbable freak event

that it would never ever happen anywhere else.

Now the prevailing view is,

yes, the universe is teeming with life.

Everybody wants to meet an alien.

But we have to start small.

We have to learn how to walk before we can run.

GEORGE NOORY: The fascinating thing for me

is that we're only four and a half billion years old

in a universe that's close to 14 billion years old.

What would happen with some of these earthlike planets

that had a five or ten billion-year head start on us?

Gosh, you can only imagine.

NARRATOR: But what if humans

are not the only intelligent creatures

searching for life in the universe?

What if there are beings on other planets

conducting a search of their own?

And what if, in their search,

they find us before we find them?

Some believe they already have.

On October 30, 1938,

radio listeners across the United States

sat stunned as a series of news bulletins

described Martians invading Earth.

MAN (over radio): Martian cylinders are falling

all over the country.

This is the end now.

NARRATOR: While the broadcast sounded real,

it was a fictional production,

directed and narrated by Orson Welles.

Incredibly, many of those listening

believed it to be true, and panicked.

Newspaper reports described families

fleeing their homes for the mountains,

while others armed themselves with weapons

and prepared to fight off the alien invaders.

It was just presented, maybe, with a brief introduction

saying it was not really happening.

But from then on, it was played as if it was really happening.

Well, most people who heard that

thought that it was really happening.

HARRISON: People became upset.

Some of those literally headed for the hills.

They drove places to try to, uh,

pick up other people, family and friends.

They reported to the army for duty.

NARRATOR: The response to this fictional alien attack

resulted in many people preparing for the worst.

But if the public's reaction to a radio dramatization

resulted in a nationwide wave of terror,

what would happen if they really came?

Los Angeles, California.

In the early months of 1942, the city was on edge.

The recent surprise attack on Pearl Harbor

had propelled America into World War II,

and the threat of a Japanese invasion,

by sea or by air, kept the military on full alert.

CHRIS PITTMAN: Pearl Harbor was a very recent memory for people.

People were in high alert.

There was a great deal of suspicion.

Japanese-Americans were being put in internment camps.

There were German U-boats in the Atlantic,

Japanese submarines in the Pacific,

and people were very fearful.

NARRATOR: In a well-organized defense operation,

air-raid wardens and the coast guard

were monitoring the Pacific shoreline as never before.

ALBERT METZ: The war had started.

I was a 13-year-old kid, and...

this one night, which was February 1942,

the sirens started wailing in the middle of the night.

Blackout.

(sirens wailing)

And we'd had several blackouts before this.

NARRATOR: On February 25,

between the hours of 3:12 and 4:15 a.m.,

the 37th Coast Artillery Brigade in Los Angeles

fired off a barrage of antiaircraft shells

at an unidentified flying object.

NEWSMAN: Watchers on the rooftop

of the Columbia Broadcasting Building

in the heart of Hollywood

could plainly see the flashes of guns and searchlights

sweeping the skies in a wide arc

along the coastal area.

C. SCOTT LITTLETON: I think what woke me up initially

was the sound of antiaircraft guns.

I jumped out of bed, and my parents were up.

My father was an air-raid warden.

He figured, this has to be the real thing.

DOROTHY MATICH: My mother was telling my brother and I,

"Get under the bed! Get under the bed!

Stay there!"

And, of course, we got out and we peeked.

There was all this firing.

It was almost like a Fourth of July.

METZ: I started hearing a lot of loud explosions.

My brother and I looked out the bedroom window,

saw searchlights twisting and turning in the sky.

NARRATOR: But what was the strange UFO

that the searchlights were focused on?

Where had it come from?

Japan?

Or somewhere from out of this world?

Could this incredible photograph,

published the next morning in the Los Angeles Times,

provide the proof?

Could ancient astronaut theorists

have been right all along?

It was practically overhead-- and I mean overhead.

NARRATOR: Retired anthropology professor,

C. Scott Littleton, was nine years old

and growing up in Hermosa Beach

when he spotted the strange object

hovering right over his house.

LITTLETON: We saw what my mother always called a "silver bug."

I'd characterize it today as a lozenge, a long oval.

It was something I'll never ever forget.

It was caught in searchlight beams,

and antiaircraft shells were exploding all around it.

It gradually went like this,

and then began to lose altitude a little bit

as it moved over what had to have been Redondo Beach.

We lost track of it, but the banging continued.

And very quickly afterward, I saw-- we all saw--

a flight of planes

following the track of the object going overhead,

anywhere from three to five interceptors,

clearly piston-driven U.S. planes.

No one has ever admitted that those planes were in the sky.

Our first thought immediately

was a Japanese observation plane.

Later, the Japanese records definitively prove

there were no Japanese planes over Southern California

that night, or indeed ever.

NARRATOR: After ruling out the possibility

that a Japanese plane had invaded American airspace,

Secretary of the Navy Frank Knox

attributed the incident to "war nerves."

But Secretary of War Henry Stimson

quickly refuted this explanation,

defensively declaring that an actual aircraft

had been the target of the assault.

To this day, no one seems to know just what-- or who--

was hovering over Los Angeles that night.

Some claimed that the Los Angeles air raid

was nothing more than an elaborate training exercise,

a show put on by the military

to keep citizens on the ready in case of a real attack.

Others alleged that the unidentified flying object

was, in fact, a barrage balloon

that had broken loose from its tether.

But even that explanation doesn't seem credible

to those who witnessed the actual event.

One place where there were barrage balloons

that were anchored above the aircraft plants

in El Segundo, Douglas North American.

It would have to have slipped its tether,

floated north up to the Santa Monica Mountains,

and then back down this way.

Barrage balloons don't maneuver like that.

NARRATOR: Regardless of the controversy,

one fact is undisputed:

an estimated 14,000 shells

were fired at the strange object,

and shrapnel rained from the sky for over an hour.

But what were the guns aimed at?

Would the army really have put

civilian lives in danger for a drill?

TOM HORSFALL: Major panic.

Six people got killed, uh, due to car accidents

and hit by falling shrapnel.

LITTLETON: A friend of mine said he witnessed a piece of shrapnel

go through his neighbor's garage roof.

So, oh, yeah, there was some damage from falling shrapnel.

MATICH: The next morning,

there was something in our backyard

my mother told me to go roll up--

it was, like, a tarp or something.

And when I bent down-- or kneeled down-- in the grass,

I cut my knee, and I have my piece of shrapnel.

I've kept it all these years.

There's my shrapnel, and it's very sharp.

LITTLETON: By a process of elimination,

the most efficient-- and I say this as a scholar--

the most efficient explanation

is that it was what we would call today a UFO--

something not of this world,

something that belonged to another technology.

If that’s true, then this event

was one of the largest mass UFO sightings in history.

Over a million people saw it.

NARRATOR: But whether it was a UFO or not,

the memories remain vivid for those

who saw something in the sky that night.

So vivid, in fact, that many of them gather each year

at Fort MacArthur, in San Pedro, California,

to reenact this mysterious event.

HORSFALL: The city went crazy.

They thought it was

we were being attacked by Japanese planes.

Some theories said weather balloon.

Others said, you know,

"Oh, I saw a plane, I know I saw a plane,"

and others say, "Nope, no such plane."

MATICH: Back then, it was a scary thing. I think to this day

they don't know what they were firing at--

if it was a weather balloon or flying saucers.

NARRATOR: But for those who believe

they saw an alien craft that night,

one important question remains:

What happened to it?

LITTLETON: The rumor is that it finally crashed in the water

and was recovered by navy divers.

So maybe it was wounded, and it crashed,

and this might explain why the military

was so quick to react to Roswell five years later.

Because they may already have had at least some inkling

of what they would find there.

NARRATOR: Was Earth really visited by an alien spacecraft

on the morning of February 25, 1942?

And could the global threats

posed by World War II have provided a trigger?

Perhaps the idea is not as far-fetched as some would think.

Is it possible that alien spacecraft

could have been mistaken for enemy fighter planes

in Adolf Hitler's Germany?

NARRATOR: In his 1993 book,

The Gods of Eden, author William Bramley

theorized that extraterrestrials played a part

in nearly every catastrophe in human history,

and have even used war as a means to control the growth

of the human population.

But while many are skeptical about Bramley's claims,

there is one thing on which they agree.

That the number of reported UFO sightings

always increases during wartime.

BIRNES: In times of war,

when vast civilizations are in conflict,

and in conflict so terrible

that it seems as though the civilizations

will wipe themselves out,

suddenly, out of nowhere, UFOs appear.

NARRATOR: While skeptics and military historians

attribute these alleged sightings

to war nerves or stress, those who believe in UFOs

find the number of instances hard to dismiss.

When World War II broke out in September of 1939,

there were numerous reports of unidentified flying objects

spotted over Hitler's Germany.

Although the term, UFO, had not yet been coined,

the Allies believed the bogeys, as they were then known,

were new fighter planes being developed by the Nazis.

But the first combat bomber jets,

the German Messerschmitt ME-262,

weren't deployed by the German Air Force until 1943.

PITTMAN: It certainly doesn't escape notice

just how advanced the Nazi propulsion systems

and their aeronautics technology really was.

They had the first operational jet fighter to see combat.

They were building and test-flying aircraft

that look incredibly similar

to UFOs that are reported even today.

They had greatly advanced rocket technology.

There have long been rumors about Nazi projects

to build aircraft using UFO technology.

BIRNES: At the end of the 19th century,

there was Aleister Crowley,

H.G. Wells, Bram Stoker, who wrote Dracula,

and Jules Verne, who wrote From Earth to the Moon.

They were in a society called the Golden Dawn.

In that society, they actually believed in the existence,

not only of UFOs, but extraterrestrials.

That culture influenced Hitler

in the late 1920s, early into the 1930s.

In looking for the origins of the Aryan race,

they went all the way to India and the Vedic texts,

which talk about UFOs.

So Hitler, in his own way, was a UFO believer,

and sought to develop his own version of a UFO,

based on the Vedic texts,

to have a dramatic wunderwaffen--

a wonderweapon-- that would end the war.

NARRATOR: Although the Nazis never developed

this so-called wonder weapon,

reports of strange flying machines

in German airspace continued throughout the war.

But just what was it that the Allied pilots were reporting?

BIRNES: In the 1940s,

as waves of American bombers

were literally obliterating German cities--

Dresden,

Hamburg,

Berlin--

in these raids, American fighter pilots

saw these balls of light coming at their planes.

They didn't know what they were.

They thought they were German secret weapons at first.

So they called them Foo Fighters.

The word, feu, in French is fire,

and these were balls of fire coming out.

So, instead of Feu Fighters, they were Foo Fighters.

PITTMAN: They were seen in large numbers

over Germany and over Western Europe,

where they were described variously as structured craft,

or simply balls of light.

NOORY: It was so important at the time

that the military began to notice it,

and they began to investigate these things.

There were hundreds of cases.

None seemed to be very harmful to planes.

But they were all over the place.

NARRATOR: Curiously, when the Foo Fighters appeared,

Allied aircraft would sometimes experience mechanical failure.

And perhaps most mystifying of all

was that some pilots reported flying right through the UFOs,

as if they had no mass.

It was never discovered what the Foo Fighters were

or where they came from, but the theory

that they were some sort of German secret weapon

was widely accepted among Allied pilots at the time.

But could the Third Reich have possessed technology

more advanced than even our most modern aircraft?

Some believe what the Nazis had developed

was an advanced mechanism that scientists

are still working on today-- mercury-powered

antigravity technology.

This involves mercury being in a closed system.

Like a glass bulb.

Once that mercury becomes spinning in a gyroscopic manner

within a closed system, that creates a lift.

It's electrified lift.

It's also a very bright light.

And, in fact, many UFOs are described as exactly that.

Towards the end of World War II,

the Germans started producing massive amounts of mercury.

And, in fact, a number of the U-boats

that were later sunk--

one was sunk near Singapore, another in Norway--

only a few years ago, they actually found it,

and its entire cargo was mercury.

What the few historians

have actually written about Foo Fighters,

which is still apparently a secret today,

is that they were a kind of mercury plasma ball.

And the purpose of the Foo Fighters

was to make a highly pulsed magnetic charge

and field around the bombers,

which would then cut out the engines and interfere

with the electrical systems in the planes.

NARRATOR: Could Foo Fighters

really have been based on extraterrestrial technology?

If so, where did the Germans get it?

UFO theorists point to the discovery of a flying saucer

that allegedly crashed in the Black Forest,

near Freiburg, Germany, in 1936.

Some believe German scientists repaired the craft

to test its energy and propulsion systems,

and through reverse engineering, were able to replicate

some of these so-called alien technologies.

L.A. MARZULLI: Did the Nazis take this craft,

and was there some sort of a pact that happened there?

Did the Nazis... did they retrieve bodies?

It's hard to pin down how much they had.

Was there contact?

NOORY: There's always been that theory--

that they had a captured craft,

and that they were reverse engineering it.

It's very possible.

They were truly way more advanced

than any culture at the time.

Thank God for the American know-how,

because we were combating them

with our own kind of knowledge and technology, as well.

BOB FRISBEE: After World War II,

there was an exercise mounted by the Americans

called Operation Paperclip.

The Allies had been confronted

with all this amazing technology from Germany.

The jet engines, airplanes,

the rocket engine airplanes, all these amazing devices.

To give you an example of some of the material

that was collected by Operation Paperclip,

right at the end of the war, Von Braun and his team

had begun designing multistage rockets

capable of reaching the United States.

They also had plans for a space station,

the classic circular sci-fi space station,

and on this, they had a huge sunlight collector,

a mirror that was designed to focus sunlight

down on the Earth as a kind of death ray.

There were all these wild ideas coming out of that team

that turned it into a very valuable coup

for the United States.

Ultimately, it was Von Braun

who built the Saturn Five rocket

that took people to the moon.

NARRATOR: The story of the World War II Foo Fighters,

much like that of the Battle of Los Angeles,

has been largely forgotten

or dismissed by traditional historians.

But an event that happened just two years after the war

had even the skeptics wondering.

What if aliens really did exist?

And could one of their craft have crashed to Earth?

Mainstream archeologists have long rejected the notion

that extraterrestrial beings had a hand in creating

the pyramids of Egypt.

Theologians and religious scholars refute the idea

that stories of the Bible or the Mahabharata

could be describing alien encounters.

And governments throughout history

have officially denied reports that the Earth

has been visited by flying saucers.

But on July 8, 1947, a UFO sighting

was reported that even the United States Government

had trouble denying.

Why? Because this time,

the report was issued by the U.S. Army.

I'm walking on the Foster Ranch

between Corona and Roswell, New Mexico,

not far from what is called

the debris field right over that hill.

And that debris field

refers to headlines back in July of 1947

about a disc-- one of those mysterious UFOs--

actually crashing right out here.

(thunder crashing)

NARRATOR: One night in early July, 1947,

a major thunderstorm rolled across New Mexico.

The next morning,

rancher Mac Brazel went out to check on the damage.

JULIE SHUSTER: Mac Brazel went out to make sure

everything was where it was supposed to be.

And he came across this really extensive area of debris,

stuff he had never seen before.

He brought it to the local sheriff's office.

In 1947, Roswell was home to Roswell ArmyAir Field.

The sheriff called the base,

the base sent Major Jesse Marcel,

and at that point, it basically became a military site,

as they gathered up every bit of debris they could find.

NARRATOR: In their initial report,

Army officials made a vague claim of having started

the recovery of the debris "sometime last week."

But why didn't the Army report their findings right away?

And why were they so ambiguous about the timeline?

One of the biggest things we have is the newspaper

of July 8, 1947, where Colonel Blanchard issued a order

to Lieutenant Walter Haught,

who was a public information officer, saying basically,

"We have in our possession a flying saucer;

it's being taken to Fort Worth, to higher headquarters."

Roswell was a real turning point for UFOlogy.

I think that was because the military,

for the first time, admitted

that they had a crashed disc.

And because it was admitted at the time,

of course, it caused a sensation.

SHUSTER: But then, July 9, General Ramey issued

a press release saying, no, it was a weather balloon.

And that started the best-documented

UFO cover-up ever.

NARRATOR: Army officials referred to the debris

as being part of a flying disc.

Internal memos even referenced the crash site

as having victims.

So, why, less than 24 hours later,

did they suddenly decide that what they had retrieved

was nothing more than a weather balloon?

Although Blanchard and Ramey stuck by the revised story,

Lieutenant Haught stood by the contents

of his initial report his entire life.

And those who believe him think modern technology

may have recently provided the irrefutable evidence

they have been looking for.

SHUSTER: When Major Marcel took the debris to Fort Worth,

and General Ramey spread it out to give this press conference

that it was a weather balloon, there was a picture taken,

and in his hand is a piece of paper.

It's a very little piece of paper.

I mean, and this has been blown up.

And it is a memo.

There is a leading researcher in the field

who is pulling the words out of this.

And they include things like "team at Fort Worth,"

"forwarded victims of the wreck," "pod or pan."

And so, every year that the technology improves,

General Ramey may be the one to solve it.

MOULTON HOWE: Bob Wood, a researcher in UFOs,

had received leaked documents in 1996,

and shared them with me and a few others.

This document called the Interplanetary Phenomena Unit,

with a War Department stamp dated July 22, 1947.

The most disturbing aspect of this investigation

was that there were other bodies found

not far from landing zone one, the Mac Brazel site

between Corona and Roswell that looked as if they had been

dissected as you would a frog.

It does not define, were those bodies human?

Were those bodies nonhuman?

But suddenly, for me, this electric jolt

that came into holding that document

and reading at the end of the '90s what would explain finally

that our government knew

that extraterrestrial biological entities

from somewhere else in the cosmos

was interacting with our planet for a very long time.

NARRATOR: Five years after Roswell,

the United States Air Force coined the term

Unidentified Flying Object or UFO.

In the decades since, thousands of UFOs have been reported...

-MAN: Whoa. -...photographed and videotaped

all over the world.

MAN: Oh, my God.

Perhaps one of the biggest, most revolutionary

pieces of technology to change

our view of UFOs and flying saucers

is the video cam.

MAN: Whoa, I'm getting a series of lights right there.

I got it, I got it, I got it.

BIRNES: You only have to look at what happened

in Phoenix, Arizona, in March of 1997,

when these huge flying boomerangs went

right across Phoenix, right through the whole valley,

heading south to the Mexico border.

These were all caught on cameras.

Network news caught these; local news caught these.

You saw these on CNN; you saw these on Larry King.

MAN: Oh, there it is, over to the left. -MAN 2: Wow.

BIRNES: And yes, people called them flares--

of course they did.

But, the fact is, when you see something

with your own eyes...

MAN: Look, dude. Pat, you got it?

MAN 2: I see it.

BIRNES: ...even if it's on a video camera,

suddenly your perspective changes.

MAN: And that middle one is moving quick.

It's only the beginning, you guys.

So, now, according to recent polls--

Gallup polls and Roper polls--

well over 50% of Americans believe

that flying saucers exist,

and close to 50% believe that the government knows

that flying saucers exist,

and that the government is hiding that fact.

NARRATOR: But why so many UFO sightings after Roswell?

Is it a coincidence?

Or is the world's growing belief in aliens providing cover

for those who might previously have been too afraid of ridicule

to come forward?

Perhaps there is another reason.

Perhaps there are more sightings

because there is a genuine increase in alien visitations...

...ever since the dawn of the Space Age.

BRAMLEY: There had been plenty of stories

of UFOs and aliens

prior to that-- a lot of sightings.

They weren't as widely reported somewhat also because

World War II had been going on, prior to that.

But because now we had a crash

and there was more room in the newspaper, so to speak,

I think that really helped the subject take off.

NARRATOR: If, as some suggest,

aliens from other worlds truly are among us

and have done their best to keep themselves hidden

for thousands of years,

will they ever reveal their presence?

More importantly, what happens if they do?

And what if it is already happening?

NARRATOR: In March, 2010, a mysterious pulsating light

floated over Cleveland, Ohio, for 1 1 consecutive nights.

MAN: We're having a sighting right now over the lake.

I'm going to say 270 degrees south.

There are, uh, two objects.

One is coming up from the left.

These are extremely close to each other.

There's absolutely no way these are planes.

Right now, uh, what's happening is the initial object

that came out-- it's sitting there, it's hovering,

it's getting extremely bright.

It's illuminating different colors.

And the second object appeared from, I'm going to say,

the top left of it.

And now it looks like it's moving around it.

Wow!

They completely just switched spots.

Oh, my God, this is beautiful.

It knows we're watching. It knows we're watching.

NARRATOR: The Cleveland sighting is

one of thousands reported each year.

And while many are proved to be false alarms,

others are not so easily discredited.

-MAN: Right below it. -MAN 2: Right below it.

A big bright white flash just occurred.

NARRATOR: In 1991, Britain's Ministry of Defence

assigned author and journalist Nick Pope to track

the hundreds of sightings reported

over England, Scotland and Wales every year.

NICK POPE: The Ministry of Defence has been

looking at the UFO issue since the 1950s.

And the whole reason for looking at these UFO sightings

is not necessarily because the department corporately believes

in extraterrestrial visitation.

It's more to do with keeping a watchful eye

on any unusual activity in British airspace.

Clearly if there's something there that's a little bit

out of the ordinary, we want to know about it.

My beliefs when I was given this job were, I think,

what on earth have I let myself in for here?

I had no particular knowledge or interest in the UFO phenomenon.

Certainly no belief in anything unusual.

But the more I looked back through the archive

of old files, and the more I began to investigate the ones

that were being reported to me on a daily basis,

I began to change my mind, and realized that some of these

UFO sightings couldn't be explained in conventional terms.

MAN: It's definitely moving.

NARRATOR: Many of the most intriguing cases Pope researched

involved eyewitness reports from pilots, police

and military officers, while others featured

classified radar, video or photographic evidence.

NICK POPE: One case that was a particular turning point for me

was the so-called Cosford Incident.

Now, Cosford is a military base in the United Kingdom.

And on the particular night in question,

which was 30th of March, 1993, there was a wave of sightings

over a period of about six hours.

And there were many police and military witnesses.

And two Air Force bases, Cosford and Shawbury,

were directly overflown by a vast triangular shaped craft.

Now, the meteorological officer at one of these bases

described this to me as the size of a jumbo jet

hovering, or moving very, very slowly,

and then accelerating away to the horizon at incredible speed.

He said many times faster than a military jet.

And this was a man with eight years experience

in the air force.

This sighting was thoroughly investigated not only by

private UFO investigators, but also by the British Government,

who were unable to explain all of the sightings

reported during this incident.

NARRATOR: Another intriguing British UFO sighting

took place in December 1980.

U.S. Air Force personnel stationed in Suffolk, England,

reported seeing a brilliantly illuminated spaceship

that landed in Rendlesham Forest on two consecutive nights.

POPE: What made this case particularly unusual

is that this was not vague lights in the sky.

This was a landed metallic craft that some of the witnesses

claimed they got, uh, so close to,

they could actually touch the side of it.

One witness saw strange symbols on the hull,

which he likened to Egyptian hieroglyphs.

He made a sketch of this in his police notebook

and took some photos, though he was subsequently told

they didn't come out.

The Ministry of Defence looked at this,

and the Defence intelligence staff

assessed radiation readings that had been taken

at the landing site as being

"significantly higher than background."

And that's a direct quote from the government's own assessment.

PITTMAN: The British Government

generated a massive file of information

about this sighting report.

But at this date, it's very unlikely that the actual truth

about the sighting will ever be known.

NARRATOR: But in spite of the compelling eyewitness testimony,

the Ministry of Defence soon declared the case closed.

22 years later, when the government declassified files

on the Rendlesham incident, the evidence was inconclusive.

But what stood out was the credibility of

the main witnesses, who were trained military personnel.

BIRNES: Obviously, as a UFO hunter,

I've met a lot of people who've encountered UFOs.

Just flying on a plane, for example.

You're on a plane,

and suddenly the pilot comes out of the cockpit--

and this has happened on five separate occasions.

And he'll say to me,

"I saw a UFO over Phoenix; I saw a UFO over Texas;

half my crew saw a UFO."

And you'll say to the pilot, "Well, well, do you report it?"

And they say, "When the flight controller says at the airport,

"'Do you want to report a UFO sighting,'

and then bursts out laughing, what you say is, 'No."'

There are UFO sightings every single day.

Real people with real sightings of real UFOs.

It is very prevalent as more and more people talk about it.

Something is going on.

In terms of the government response to all this,

certainly in Britain,

the Ministry of Defence policy for many years has been

to try and downplay this subject.

Not really in any great sinister attempt

to cover up the truth about UFOs, whatever that might be,

but more out of embarrassment.

There are things in our airspace,

we don't know what they are, and that's not a good place

for the government and the military to be.

NARRATOR: On December 1, 2009, the British Ministry of Defence

quietly terminated its UFO project,

citing that there had been no credible evidence that UFOs

posed a potential threat to the United Kingdom.

(bell tolling)

There are a number of aspects of this decision

that were particularly controversial.

Firstly, UFO sightings are at a ten-year high

in the United Kingdom.

So it seemed the most inopportune moment

to pull the plug on 50 years of research and investigation

into the UFO mystery.

The other point that made this particularly controversial

was the way in which the decision was announced.

There was no proactive statement issued on this.

It simply said: The department will not respond

to any inquiries on this subject

and will no longer investigate sightings.

NARRATOR: One hurdle confronting those in favor of

fully disclosing classified information related to UFOs

is the fact that most mainstream scientists believe

that the study of alien phenomena

is little more than just fringe science.

It is this fear of dismissal or ridicule

that keeps many scientists hidden in the shadows.

TED PETERS: Our best scientists,

who communicate with one another around the world,

have rules of protocol, which include--

they cannot appear to be religious... (laughs)

...they cannot believe in flying saucers,

and they certainly shouldn't hang around with

anybody who believes in flying saucers.

HARRISON: But it's all done, you might say, behind closed doors,

because nobody really wants to, uh, draw attention to it.

You know that, uh, they understand, you know,

that there's a penalty associated

with this kind of research.

And so consequently, it's done, it's done "invisibly."

ROBERT BAUVAL: To be blockaded and stopped by worries

about peer reviews and so forth, to me, is wrong.

We can speculate whether there is life outside this planet.

We can speculate whether there has been a contact

with, with other civilizations. Why not?

NARRATOR: But as more scientists openly embrace the probability

that there is intelligent life existing

elsewhere in the universe,

will the belief that alien beings are visiting us

also become more accepted?

What might be the reaction today if extraterrestrials were to

actually arrive on Earth and make themselves known to us?

Countless science fiction books and films tend to portray aliens

coming either to warn us or destroy us.

BIRNES: Since the 1960s, people have been thinking about:

Well, what do we do?

Do we have a Day The Earth Stood Still scenario if aliens come?

Do they warn us that our planet's facing disaster?

Do they attack us,

the way the Martians did in War of the Worlds?

Well, the answer is more complicated than it seems.

It's not just somebody landing and saying,

"Take me to your leader."

TSOUKALOS: The general consensus today

is that if extraterrestrials were to show up tomorrow,

they'd be hostile, and they would want to enslave us

and-and battle us and-and destroy us

and all this crazy stuff.

In my opinion, that won't be the case,

because any civilization that's mastered to travel

interstellar space would be benevolent

to a lesser advanced society, technologically speaking.

DAVIES: A simple statistic shows that if we make contact

with extraterrestrial civilization,

we are the new kids on the block.

We're the ones who are at the back of the queue

when it comes to intelligence.

So, uh, they'll be teaching us stuff.

We won't have a great deal to teach them.

JEFF PECKMAN: There are a wide range of benefits

that can be derived from accepting that we have neighbors

in the galaxy that are visiting us.

There are reports of medical treatments

that have been performed for the benefit

of several people who have had contact.

There are advanced energy technologies.

Reports are that some of these have been

reverse-engineered already and are used in military craft.

There are communications technologies.

So, really, any area of life that we have could be

beneficially impacted by acknowledging that there are

these other people out there, that they have information,

knowledge that they can share with us that would benefit us.

HARRISON: It's going to depend how the discovery comes about.

If, in fact, it's a distant radio broadcast,

we might expect one thing.

If, in fact, there's, uh, some type of visitation that fits in

with beliefs about UFOs, that might be something else.

But, on the whole, I think people are much more prepared

for, uh, shall we say "contact"?

NARRATOR: Many who believe contact with extraterrestrials

is inevitable suggest governments

need to prepare themselves.

It's a field of study known as exopolitics.

Exopolitics poses the question: What should our response be

to that situation at a societal level?

Not necessarily at a governmental level,

but actually individuals-- how can we reach out

with a hand of friendship?

STEVEN GREER: Exopolitics has really been

a grassroots movement of people concerned about this issue

and want disclosure on the UFO subject,

and also want to help organize people locally

to get the information out to their governments

and make this big change happen.

NARRATOR: But if we reach out in friendship,

what guarantee do we have that it will be returned in kind?

Many scientists, including famed theoretical physicist

Stephen Hawking, believe alien beings could pose a threat

and suggest we do everything possible to prevent contact.

BIRNES: If extraterrestrials, or aliens, were aggressive,

were warlike, and they came here,

is it a case where resistance is futile?

How do you wipe out life on planet Earth?

That's easy-- a plague.

Simple-- no UFOs,

no zorching beams from the sky, no explosions,

no Empire State Building collapsing, none of that.

We can do that.

Why can't aliens do that?

TSOUKALOS: To think that we would be able to come up with

some type of a defense mechanism or have defenses

against interstellar traveling society is ludicrous.

NARRATOR: Whether they came as friend or foe,

if extraterrestrials did land somewhere in the United States,

it's possible the aliens would be greeted by government

or military personnel wearing Hazmat suits

and testing for harmful pathogens and radiation.

Many conspiracy theorists suspect

the government's next step would be to cover up the visitation.

They cite as evidence a reputed sighting that took place

over Washington, D.C. in 1952.

BIRNES: In full view of the entire world,

a squadron, a formation of UFOs buzzed Washington

and fought our own F-93 jet fighters.

General Samford willingly and deliberately--

maybe on instructions from Harry Truman,

who was president-- lied to the American people.

We have received and analyzed

between one and two thousand reports.

Of this great mass of reports, we have been able, adequately,

to explain the great bulk of them.

BIRNES: His own Captain Ruppelt,

in his own book on flying saucers, says Samford was lying.

We have the letter from the Air Force to Dean Condon

saying "Deep-six UFOs."

So, have UFOs come to planet Earth in full view,

have manifested themselves, have shown themselves?

Yes.

Did we see it? Yes.

Was there a protocol for handling it?

Yes. That protocol was called "deny."

NARRATOR: But if an alien visitation proved undeniable,

who might be chosen

to then speak to those inside the spacecraft?

Who could best represent all the nations and interests of Earth?

SEAGER: If aliens do land on Earth,

I think we should send our best world leaders

who are the most open-minded and reasonable,

but who also have the ability

to defend themselves against those aliens.

BIRNES: In my opinion,

that's one of the reasons we have a United Nations.

Yes, it prevents wars and delivers food.

But on the other hand, just imagine

the Security Council itself convening to deal with aliens--

an image on a big screen at the United Nations.

The answer is: I think it all happened back in the 1940s,

and that was one of the reasons that Roosevelt

and Eleanor Roosevelt pushed so hard

for the formation of a United Nations

to replace the League of Nations.

Somebody had to confront the aliens.

LEVINSON: The notion that our leaders-- elected or otherwise--

should speak on our behalf,

I don't necessarily think that makes sense.

There are a lot of people who might have better ideas

than the people who are in government.

I'd like to see a profoundly democratic-- with a small D--

unauthoritarian interaction with aliens.

NARRATOR: Currently, there are no known official protocols

in place for an alien visitation.

But there are those who think that contact

with extraterrestrials is imminent,

and that our world leaders must plan for the event now.

PECKMAN: We're not alone in the universe.

We have friends and relatives out there in the galaxies.

And we need to take on this task, one way or the other,

of just getting the job done and getting to the point

where we're considering the practical details of

interacting with these friends and neighbors out there.

GREER: Who is responsible for that relationship?

Well, the State Department isn't.

The United Nations isn't.

And I think this is a very big problem.

So, well, there needs to be a diplomatic effort

to make contact with these interstellar civilizations

in such a way

that it puts wiser people in charge of that.

POPE: Even if you don't

corporately believe in extraterrestrials,

if you think the possibility of alien visitation

is vanishingly small,

the consequences if it does happen are immense.

And, therefore, it's prudent to have

something in place to deal with it.

DENNIN: Personally, I think it would be very, very exciting.

I mean, it would be just like the first time, you know,

the explorers came, um,

from Europe to the Americas and discovered

a whole new culture, and they had to interact.

Hopefully, it won't work out as some of

the bad things that occurred then;

it would be a more positive experience.

And maybe we've learned from that and we can go forward.

NARRATOR: What would happen after

any potential extraterrestrial contact

is open to much speculation.

But most people concede one thing:

The world as we know it would change dramatically.

GREER: The result would be

that the fundamentalist orthodox belief systems

of every organized religion on Earth would collapse.

Meaning that it would really bring into question

the origins of the human race, uh, the Genesis stories

and a whole lot of other issues.

BIRNES: The very structures of government

and the very structures of religion will crumble.

NARRATOR: But in 2008,

a stunning announcement was made from a very surprising source.

Proof to some that miracles, like aliens,

do indeed exist.

NARRATOR: The Vatican, Rome.

This walled enclave has been the center of power

for the Catholic Church since the fifth century.

It's not only the Pope's residence,

but a place of homage for one billion Catholics,

and represents nearly 2,000 years

of Christian teaching and tradition.

But, in 2008, the Vatican made an announcement

that some say might threaten its own existence.

The chief astronomer of the Vatican Observatory,

Father Gabriel Funes, acknowledged the possibility

alien life exists on other planets.

They basically said that belief in planetary life

outside of Earth does not negate one's belief in God.

Now, 500 years ago, if the Vatican would have said that,

they would've burned everybody on the stake.

WILLIAM FULCO: The present Pope, Benedict, of course,

has a very scientific bent.

And he respects intellectual life

in-in a way that is-is quite extraordinary.

He seemed quite open to entertain the idea:

What if there is life on other planets?

It's certainly an interesting question for a Christian.

To approach it scientifically, it challenges your belief

of how much of this you attribute to God.

NARRATOR: Many wondered about the Church's motives and timing.

Why, after centuries of belief

in man as God's supreme creation and the only intelligent life

in the universe, did the Vatican make an announcement

that could turn Christianity on its head?

Did they know something the rest of us did not?

TSOUKALOS: This is something

that is completely new in the history of the Church

that the extraterrestrial question

is not only addressed, but at the same time, it's okay.

I mean, that is a major change in opinion.

A major change in the status quo.

And I ask: Why?

Would it have huge ramifications?

Of course.

Does it change anything?

Of course.

But at the same time, would that change religion

or belief in God?

Not really.

Some people say, well,

the Catholic Church must know something.

Uh, maybe they're trying to get ahead of the game here.

On the other hand, it may just be that they're being

very clever and simply trying to cover all the bases,

in case there is some great announcement

or discovery about alien life.

Because, make no mistake about it,

if it is announced that alien life has been discovered,

people are going to look to their religious leaders for

some sort of guidance about this, whether it's Christians,

Jews, Muslims, Hindus.

CHRIS CORBALLY: If extraterrestrial life was found,

then the Church would react presumably as it does

with any data-- see what there is.

I don't think there would be any conflict

in the way that we look on our humanity.

What we would find is that God creates

intelligent life in a variety of ways.

And I think what we would learn from that is,

we can't restrict God to any one mode

of making intelligent life.

NARRATOR: The idea that intelligent life exists

elsewhere in the universe has been debated by

religious leaders, historians and scientists.

But not everyone agrees how its proof would affect

human spirituality or the many religious institutions.

PETERS: What would happen to our interpretation

of the Book of Genesis?

Well, the Book of Genesis looks at the universe

from the point of view of Earth.

We look at the sun, we look at the moon, we look at the stars.

So, to realize that the Earth is just

one small, pale-blue dot in this immense universe,

I think it would only expand our interpretation of Genesis.

I don't think it would, uh, change it

in any fundamental way.

FULCO: It's an interesting question for Christianity

in general, since Christianity would teach that salvation

comes through Jesus, who was apparently an earthling.

Um, what do you do if there are people on Mars?

Are they saved?

According to our viewpoint, um, I don't know.

DAVIES: Christians have always had this problem

that if there are aliens out there, are they not to be saved?

It's not a problem for Jews.

Certainly not a problem for Buddhists or Hindus.

But Christians are in a particular fix.

For a very simple reason that Christianity alone

among the world's religions has an incarnation.

What they mean by that is that God became incarnate

in the form of Jesus Christ, in order to be the savior.

When you talk to Christians, they sort of say,

"Oh, well, there isn't a problem really because, you know,

"we've accommodated Galileo, we've accommodated Darwin.

Why can't we accommodate E.T.?"

Well, I think there's a big difference.

PAUL LEVINSON: I think science and religion have more in common

than perhaps the popular perception suggests.

On one hand, we have science,

which deals with reason and fact.

On the other hand, we have religion,

which deals with faith.

Science is an evolving proposition,

and what we know today will almost certainly be reformed

and maybe even replaced at some point in the future.

So, to think that science somehow provides the truth

in contrast to religion, I think is a mistake.

NARRATOR: While scientists and religious leaders

may still ponder the notion of aliens visiting Earth,

ancient astronaut theorists claim that the evidence exists

in plain sight around the world.

But if this theory was accepted, would we have to change

our beliefs about our knowledge, our history

and the very beginnings of human civilization?

For thousands of years,

humans have recorded events that seem to suggest

other-worldly beings came down from the skies to visit Earth.

These ancient visitations represent the foundations

of those who believe Earth was visited in the past

by advanced beings from other planets.

These sightings are also said to explain

many mysteries surrounding our past.

ERICH V. DANIKEN: The most important was religion.

The gods have descended to our ancestors' time.

Now it enters into the holy books, into mythology.

Now, later, people try-- reason the people try

to understand this, they make out religions of it.

But the core is

extraterrestrials have come here.

That was the beginning of all the big religions.

There are two main components why we are

who we are today as a species.

One, someone tampered with our genetic makeup,

and two, technology.

Because all of a sudden, we were doing and building things

that we would still have difficulties recreating today.

And the ancient texts are very clear

that many of our achievements in the past

happened due to a direct intervention

of extraterrestrials that arrived from the skies.

NARRATOR: Ancient astronaut theorists also cite as evidence

the amazing similarities between

isolated cultures all over the planet.

Why did different civilizations build immense

megalithic structures to honor otherworldly beings?

Why do so many ancient texts

seem to reference men flying in the sky?

And why do the ancient Egyptians, Hopi Indians

and the Dogon tribe of North Africa

all believe their ancestors came from

what we know as the constellation Sirius?

TSOUKALOS: If the extraterrestrials wanted

to leave behind a message of where they came from,

then it would serve them very well

to build those structures with a reference

to their location of origin.

So, if we have connections to the Sirius star system,

well, it would lend us to believe that here we have

a reference of where they might come from.

NARRATOR: The question of extraterrestrial life

is as old as civilization itself.

Ancient astronaut theorists, as well as many noted scientists,

point to the immense size of the universe and concede

that other beings must exist somewhere else besides Earth.

But the question remains:

Did aliens visit us in the past?

And is it happening again?

The way we look at history is very fragile.

Any discovery, which is made somewhere,

can change the way we look upon history.

I think if we were to identify that an alien presence

has been here on Earth in the past,

I think there are two very important questions.

Did E.T. just come by and visit, and then disappear?

Or did actually E.T. come, stay and contribute to civilization?

I think the second one is far more important,

because it shows us far more.

It actually rewrites mankind's identity rather than

just whether or not, you know, some extraterrestrial being

came here on a holiday and then left

without really leaving something behind.

TSOUKALOS: In all of the ancient texts,

there is one thing that is very clear,

and that is that these gods one day will return.

NARRATOR: But short of an alien spacecraft

landing on the White House lawn,

ancient astronaut theorists know there will always be skeptics.

PECKMAN: People are always looking for

an ultimate proof of the existence of

extraterrestrial intelligent beings.

But I think a more useful and honest question is:

How much and what kind of evidence would be enough for you

to believe that they're out there,

that they have been visiting us?

GRAHAM HANCOCK: I believe, through the experiences

that shamans have been documenting and reporting

for tens of thousands of years, that, uh, we are in contact

with entities and beings that are not of this Earth.

But precisely what those entities and beings are

remains to be established.

PITTMAN: There is evidence that indicates

that it's possible that humans were visited

by extraterrestrials in the distant past.

And if we are too quick to discard that possibility,

then we might be shutting ourselves out from something

that might be really fascinating and might take us

to a, to a next level that we can't even imagine.

DAVID CHILDRESS: It's very possible that

those extraterrestrials who've allegedly been coming here

for thousands of years, I mean, they are us.

They look like us.

And, in fact, that's part again of the Bible,

in that the God

or the gods created us in their image.

I mean, we are to be like them.

We are to look like them.

We are to have the technology they have.

We're to go into space, just like they did.

I think there is life, simple life, bacterial life,

microbial life on other planets.

I think we're going to find that.

And who knows?

Maybe one day we'll find some other planet

that's capable of sustaining life that has evolved people

over a long period of time that are also looking up

at the stars, wondering: Is there anybody else out there?

Are we the only ones?

TSOUKALOS: We are a species of explorers.

So, ultimately, we will come across

some other type of intelligence.

And when that happens,

if that society, technologically speaking,

is primitive, we'll become ancient astronauts

with that culture.

HANCOCK: Human history has become too much a matter

of dogma, uh, taught by professionals

in ivory towers, as though it's all fact.

Actually, much of human history is up for grabs.

The further back you go,

the more that the history that's taught in the schools

and universities begins to look like some kind of fairy story.

BAUVAL: We have logic, we have intuition, we have our senses.

And to limit ourselves

through the scientific route is a mistake.

We can send people on the moon,

we can plan journeys to Mars, we can make cell phones.

But we haven't explained the fundamental questions

that we should be dealing with.

Where do we come from?

What are we supposed to do here?

And where are we going?

We really have not come with the answers, and we know no better

than the ancients that we're trying to explain.

TSOUKALOS: Exploring the ancient astronaut theory is

the ultimate quest to find out: Where did we come from?

How did it all begin?

And most importantly, who are we?

And the ancient astronaut theory

has the capability of answering all those questions.