All language subtitles for Ancient.Aliens.S22E12.1080p.WEB.h264-EDITH_track3_[eng]

[Narrator]
A mathematical message

encoded on opposite sides
of the globe.

Complex crop circles

designed to convey
sound frequencies.

And colossal figures

that can only be seen
from the sky.

♪ ♪

When author and ancient
astronaut theorist

Erich von Däniken wrote
Chariots of the Gods?

he presented
a groundbreaking theory.

He suggested
that extraterrestrials

not only came to Earth
in the distant past,

but that they left hidden
messages for us to discover

once we had developed the right
technology to decipher them.

One compelling example
are geoglyphs,

massive shapes and figures
carved into the landscape

that are only fully visible
from the sky.

[Narrator] Saudi Arabia. 2004.

While exploring the ancient
lava fields of Harrat Khaybar,

amateur archaeologist
Dr. Abdullah Al-Saeed

comes upon a number of
what appear to be stone walls,

each approximately
three feet high.

From the ground level,
Dr. Al-Saeed concludes

that the structures have no
discernable pattern or purpose.

That is,
not until four years later,

when he obtains satellite photos
of the very same area.

What he sees astounds him.

There, detectable from the sky,

are a vast collection of
more than 400 stone enclosures.

Known to the local Bedouin as
"The Works of the Old Men,"

these mysterious structures
are quickly examined

and are revealed to stretch
for hundreds of miles.

[Andrew Collins] They were
within what's referred to as--

as a lava field of activity.

And are generally described

either as kites...

...or as gates,

which are more
rectilinear forms of them.

And there are literally
hundreds of these.

In fact, they stretch
all the way from Saudi Arabia

right away across to Jordan

and into Syria.

[Hugh Newman] They're kind of
like angular pyramids, almost,

going off into
the distance like runways,

widening at one end to
being short at the other end.

[Narrator]
Although no record exists

indicating when
these structures were built,

who built them, or why,

the predominant theory
among mainstream archaeologists

is that they were constructed
for hunting purposes,

many thousands of years ago.

What we think they are,
are prehistoric hunting sites,

where gazelle and other animals

would be driven
into the enclosure,

and then, on the outsides
of the enclosure,

pits were dug, and the animals
would fall into the pits.

The kites, when you visit them
on the ground,

are really hard to find.

In the air,
you get the whole pattern.

There are literally
thousands of them.

And they must have been in use
for thousands of years.

And why did
they fall into disuse?

That's an answer
we haven't yet got.

[Narrator]
Although the theory that

the stone structures were used

for hunting purposes
is compelling,

ancient astronaut
theorists argue

that if these structures
were really used

for hunting gazelle,

the walls would have needed to
be more than three feet high,

since a gazelle can leap more
than ten feet into the air.

Instead, they suggest

that because the structures
are only viewable from the air,

they should be
considered geoglyphs.

[Paul Bahn]
A geoglyph is just, basically,

a drawing on the landscape.

Usually quite large-scale.

Most geoglyphs are in deserts,

and in deserts
you get a phenomenon

which we call desert varnish.

It's just a natural dark patina
that builds up on the surface.

And so, if you move
the dark parts to one side,

expose the lighter soil
or sand underneath,

that is one way
of making a drawing.

The second basic technique

is to use the dark stones

and pile them together
to make shapes,

geometric shapes,
animal shapes or whatever.

And the third basic technique

is simply a combination
of the two.

You move things to one side
to expose lightness,

you use the dark stones
to make patterns.

So you get very nice
combination of the two.

In recent years,
thanks to modern technology,

and particularly
satellite photographs,

there has been an explosion
in new discoveries

of-of geoglyphs that
we didn't know about before.

[Collins] The interesting fact
about all of these

is that they point
towards the sky.

And what might this tell us?

Well, the first thing is
that many of the geoglyphs

that we know today
were only discovered

once aerial survey started
in around the 1920s.

All of them were
only really revealed

once aircraft got up
into the air.

And this tells us something
very, very important.

[Bahn] Most geoglyphs really
only make sense from above.

It therefore seems that
they would be messages

to something non-human,
something up there.

[Narrator] When the
now-legendary Nazca Lines

of Peru were first
discovered in 1927,

they were considered
a unique phenomenon.

But now, with the benefit
of satellite imagery,

thousands of ancient geoglyphs
are being found

all over the world:

in Kazakhstan,

in the southwestern
United States,

in the Atacama Desert of Chile

and in Bolivia.

[Collins] Almost everywhere
around the world,

we find what are known
as geoglyphs,

whether they be
the Nazca Lines in Peru,

British geoglyphs,

to those in the Middle East,

they're something
that are virtually universal

around the world,

and they've been appearing
for many hundreds of years.

[Narrator]
But why would ancient people

in so many different locations
around the world

all be making signs that can
only be seen from above?

We don't know for sure what

ancient peoples were trying to
communicate through geoglyphs,

but the most important thing is

the amount of time and effort
that went into building them.

They're not quick sketches.

They're, many of them,
whole community projects.

And the time that
you spend working on them

is time
not spent gathering food,

not spent defending your land.

It's time not spent
looking after your children.

So, the first thing
that they communicate

is to the community itself,

what is important
to the community.

[Narrator]
But could there be another,

even more incredible
explanation?

Is it possible that
these ancient geoglyphs

were created
not for a terrestrial purpose

but for an extraterrestrial one?

Ancient astronaut
theorists say yes,

and suggest
further clues can be found

by examining similar
shapes and symbols

that occur
on a much smaller scale.

Geoglyphs are
gigantic-sized versions of

what we know as petroglyphs,

the most obvious being
the rock art that we'd see

on surfaces of stone rock
around the world

that date back many,
many thousands of years.

Petroglyphs are images
carved into stones

or incised or hammered away.

They occur all over the world,

from Australia up through Asia,

Europe, Africa,
through the Americas.

[Narrator]
Perhaps more intriguing

than the petroglyphs themselves

are the eerie similarities
between them

and their geoglyphic siblings.

We see certain symbols
recurring again and again.

There are many geometric forms.

These take the form of spirals,

of concentric rings,

and other more rectilinear
or abstract designs.

They're something
that are virtually

universal around the world.

One of the most
interesting geoglyphs

that you have at Nazca is
the Sun, Star, Cross geoglyph,

which is really
a very complicated,

huge mandala of interconnected
stars and triangles.

And it's something we see
all over the world,

and in Tibet and India
as mandalas, and even yantras.

So, things like this,

that are so
geometrically complicated

and are found
all over the world,

indicates that
there was some kind of

worldwide symbolic language

that was brought here
by a higher intelligence,

probably extraterrestrials.

In 2005, an unusual feature

was discovered in central Canada

that some believe
contains the best evidence yet

of a hidden message left
by extraterrestrial visitors.

It's a colossal geoglyph
that has become known

as the Badlands Guardian.

[Narrator] Gravelbourg,
Saskatchewan.

2005.

53-year-old grandmother
Lynn Hickox

is scanning GPS driving
directions to a local museum

on satellite view
when something catches her eye:

a geographical feature that
bears a striking resemblance

to a human face.

It looks so much like
a man-made structure

that she posts the image
on a message board.

Almost overnight,
the image goes viral

and becomes known
far and wide

as "the Badlands Guardian."

It is quite striking.

It is clearly a face.

The brow, the nose, the lips,
the chin are well-formed.

The headdress, a little less so,

but clearly could
be seen as feathers.

The Badlands Guardian
appears to be

a huge geoglyph
near Alberta, Canada.

And to see it from Google Earth
or from satellite imagery,

you would think it was created
by people many, many years ago.

[William Saunders]
Badlands Guardian is a bust,

or a head and shoulders
presentation,

of a male Indigenous person.

It is so striking
because that is

the Indigenous people
of the area.

It doesn't look like
a Scotsman wearing a kilt,

doesn't look like
an African warrior,

it looks like an Indigenous,
uh, native to the area.

[Narrator] Is it possible that
the likeness of a human face

naturally formed in the earth?

Many who have examined
the Badlands Guardian

suggest that, based on the
amount of detail it displays,

this is highly unlikely.

When the mainstream
scientific community looks

at the Badlands Guardian,

their first explanation is that

it was created by weathering,
rain and water runoff.

But there's just so much detail

that we're seeing
in this formation

that it goes way beyond
anything nature could make.

It not only has
basic facial features,

it has secondary facial
features, such as the eyelid.

The only thing missing from

the Badlands Guardian
is an ear feature.

Now, the interesting thing
about that is,

the local government in Canada,

they had found
a gas deposit there.

Right where the ear should be.

There might have been an ear
there at one time,

but now, because they put
an access road there

and they built this gas feature,
that was all erased.

Archaeologists are often
mistaken about ancient sites.

And what is actually a pyramid

that's now, say,
covered in soil

and has a forest on it

can be mistaken
for just a natural hill.

This has happened in...
in South America, in China.

Archaeologists are continually

finding that things
they think are natural

are actually artificial.

[Narrator]
Some of the geoglyphs found

around the world were formed

simply by removing
the top layer of soil

to expose the lighter-colored
dirt underneath.

But if the Badlands Guardian
is also a geoglyph,

creating it would have been
an enormous undertaking.

The massive, concave formation

is almost half a mile long,

and is over 1,100 feet wide.

For comparison, the Mount
Rushmore National Monument

in South Dakota,
which was completed in 1941,

is approximately 80 feet tall
and 200 feet wide.

And while it is only
a fraction of the size

of the Badlands Guardian,
constructing it required

an enormous amount of work,

even with modern technology.

The carving officially started
in 1927,

and it was considered
complete in 1941.

My grandfather was
on the mountain

approximately
from 1933 to 1941.

He was chief carver
on Mount Rushmore.

It took about 400 workers.

It took 14 years.

And when I think about
the amount of time and effort

that it took
for people in the '30s

to create Mount Rushmore,

I can't even begin to imagine

what the person
or persons had to do

working on something the size
of the Badlands Guardian.

I-I can't even
wrap my head around it.

How was it possible that
the people that carved these,

thousands of years ago,

were able to see
what they were doing

or know what they were doing?

They must have had assistance
by extraterrestrial beings.

[Tsoukalos] The Badlands
Guardian can only be

fully appreciated from the sky.

So you have to wonder: why?

Well, then, the answer is
people on the ground

wanted to signal
someone up in the sky.

[Narrator] For ancient
astronaut theorists,

the Badlands Guardian
could offer

some of the most compelling
new evidence

that extraterrestrial
intervention

occurred on Earth
in the distant past...

that is, if it really is
an artificial structure.

Boston, Massachusetts.

February 2019.

Aerospace engineer and satellite
imaging expert Mark Carlotto

has spent countless hours
examining

the Badlands Guardian to see
if he can determine for certain

whether it is something other
than a natural formation.

[Mark Carlotto] The image of
the Badlands Guardian is

very striking as this
Native American figure,

and some properties
that are unusual.

So I did some analysis, uh,
using some imaging software

and the height map
of the feature.

So we'll start with
an overview of

the Badlands Guardian
image here.

We see the figure in
the middle of the image here.

And notice
the surrounding landform

is very similar in morphology.

So now what we'll do is
we'll zoom up on the figure.

You can see it a little bit
more clearly, the, um...

this iconic face.

So what can we do to bring out,
you know, some information?

So, we ran a program
that extracts the height

or elevation from the figure.

And the way
it's depicted here is...

is dark is low
and bright is high.

So now, when we've--
after we've taken the image

and texture-mapped it
onto the elevation surface,

we can view it in 3D.

And, um,
now I'm moving around it

and viewing it like
we might see it in a drone.

And as you can see,
when you're looking

straight down
on the Badlands Guardian,

it's, uh, this
uncanny resemblance

to a Native American.

But as we look off-angle

and as we look at it
from ground level,

simulated ground level,

you see the illusion disappears.

So, clearly, this feature,
if it was created,

was meant to be viewed
from above.

[Travis Taylor]
To me, the Badlands Guardian

looks artificial.

It doesn't look like
a trick of nature

and that I'm suffering
from apophenia.

All humans do have apophenia,

meaning they see patterns
where patterns are not.

That's why we see Mickey Mouse
in the clouds and so on.

But this looks
too specifically like

some type of Native person
with a headdress on.

Looking at this picture,

you can see the natural
patterns of erosion.

So, it's clear to me
from this picture

that this is
an artificial structure.

High in the arid desert of Peru

is a strange,
mile-long earthwork

made up of over 5,000
shallow holes

dug out of the dirt.

What purpose
this Band of Holes served

and why it was created
remains a mystery.

But some researchers believe

that the pattern there
contains a hidden message

and point to
a nearly identical design

found thousands of miles
to the east,

in France.

[Narrator] Central Peru.

Just outside of Pisco,

at an elevation of
11,000 feet,

stretches an arid desert

known as
the Cajamarquilla Plain.

Here, thousands of holes of
varying dimensions and depths

have been dug
into a mountain range

in a pattern that runs north
and south for almost two miles.

This mysterious formation

has baffled archeologists
for decades,

and, like the Nazca Lines,

the holes can only be
appreciated in their entirety

from high above the ground.

[Tsoukalos]
In the mountains of Peru,

we have what's commonly referred
to as the Band of Holes.

It is one of the coolest places

in relation to
the ancient astronaut theory,

because who in their right mind

would go ahead
and dig all these holes?

For what?

They're a incredible mystery,

a very long-lived mystery.

Some people think it looks like
some kind of machine

was running over the territory.

Some people think
it was some kind of

systematic mining operation.

Some people say it was
just pot-hunters,

you know, looting,
looking for burials.

None of the explanations
make good sense.

[Narrator]
While the Band of Holes

continues to defy explanation,

some ancient astronaut
theorists believe

it may represent
a type of message,

a message
that can also be found

at another site
6,000 miles away.

The northwest coast of France.

Here, just south of Brittany,

lie the legendary
Carnac stones...

...an arrangement of
over 3,000 megalithic rocks

that stretch for more than two
miles across the countryside.

The megaliths of Carnac
in Brittany are just amazing.

Some of them stand
about 30 or 40 feet tall.

There are multiple avenues of
stones going right over hills.

And no one's really worked out
exactly what their purpose is.

[Narrator]
Like the Band of Holes in Peru,

the Carnac stones continue
to defy explanation.

But ancient astronaut
theorists suggest

that the clue to understanding
both mysterious sites

might be found
by comparing them side by side.

The Band of Holes runs
for approximately two miles.

So do the Carnac stones.

The width of the Band of Holes
measures eight holes across,

occasionally deviating
by one or two holes.

This, too, is often the case
with the Carnac stones.

And when viewed from high above,

the layout of the two sites
is eerily similar.

[Childress]
It would appear, in my mind,

that there's some connection

that's between Carnac, France
and Peru,

and a special code
put there for us

to find at a--
at a future time

when we could understand
these codes.

[Narrator]
Some ancient astronaut theorists

have even gone so far

as to suggest
that the Band of Holes

may have once held
some sort of standing totems...

...similar to what is
believed to have existed

at Stonehenge,

and that those totems
may have disappeared

because they were made of wood.

There are a series of postholes
that were found

all around Stonehenge

in which you can stick
sticks in the holes.

But they degraded over time

and it gradually crumbled away,

and perhaps
the same thing happened

in the Nazca Plain in Peru
with these holes.

[Narrator] Could there
really be a connection

between the Carnac stones
in France

and the Band of Holes in Peru,

as ancient astronaut theorists
suggest?

And if so, is it meant
to convey a message?

[Wilcock] If you look at
the stones at Carnac,

you see curious alignments.

And these alignments
actually duplicate

the Pythagorean triangle.

This appears to have happened
as much as 3,000 years before

Pythagoras allegedly invented
the Pythagorean triangle.

What you're seeing is remarkable
mathematical symbolism

and encoding messages

that seem to suggest
somebody wanted us to know

it was built with technology

far in excess
of what we have now.

[Erich von Däniken] Some
thousands of years in the past,

the extraterrestrials
who visited our planet

left a proof behind.

They knew that
in the far future

the humans will see
these stone patterns.

They will realize
that this is high geometry.

And sooner or later
the questions comes up,

"Have we maybe been visited
by beings from outer space?"

[Narrator] Is it possible
that these two ancient sites

are both conveying a message

left behind
by extraterrestrials?

And was it their intention

that it would one day
be deciphered by mankind?

Ancient astronaut
theorists say yes,

and claim that further clues
can be found

by investigating
magnetic anomalies

within mysterious,
colossal stone heads

unearthed in the jungles
of Central America.

A key tenet of the ancient
astronaut theory is

that extraterrestrials
left information for us

within megalithic structures
and monuments.

And a recent breakthrough
suggests

that some of
the largest statues ever built

could possibly be

ancient hard drives.

[Narrator] La Democracia,
Guatemala.

June 2019.

A team of researchers from MIT,
Harvard, and Yale announce

that they have discovered
unusual magnetic anomalies

within the colossal stone heads
attributed to the Monte Alto,

a Mesoamerican civilization

that emerged around 1800 BC.

[Childress]
Some of these statues

have very strong
magnetic fields.

The creators of these statues

were totally aware

of these magnetic fields.

And that is something that
shocked modern archaeologists,

that this rather primitive
culture, they thought,

was aware of magnetism

and that they actually chose
certain rocks

because of the magnetic field.

[Narrator]
In Mexico, similar statues

created by
the Olmec civilization

were also found to emit
magnetic anomalies.

These intricately carved heads

vary in height
from nearly five feet

to over 11 feet tall,

the largest weighing
approximately 50 tons.

Like the Monte Alto sculptures,

most of these heads were
made from basalt.

Basalt has large quantities

of-of iron and magnesium in 'em.

The Olmec were so precise

with knowing where
the magnetic fields were

that they actually
carved the structure

around these anomalies.

So, when scientists use
a magnetometer

around the stone statue,

they notice the nose
or the cheeks,

around the chin, the magnetic
fields are strongest there.

[Collins] The great heads of
the Olmec are made of basalt.

Basalt is a volcanic substance.

And the closest source
to many of these heads

is anything up to
a hundred miles away.

Now, this is interesting,

because I don't think
it's simply the case

that the basalt
was easy to sculpt

into the forms of heads.

[Williams]
Basalt is dense.

It's very, very heavy,
thick rock

and it's very difficult
to work with,

let alone carve
with rudimentary tools

like flint.

Because they range higher
on Mohs test

as far as density.

And flint is a much
softer material than basalt.

So, it's difficult
to understand how

they carved these things.

And the intricate detail
on some of them

is just incredible.

[Newman]
With these stone giants,

it really is a question
as to why they chose

these specific types of rock.

Like granite we find,
it's very crystalline.

It's also electrically
conductive.

We find basalt,
which is volcanic.

Again, this is very magnetic.

And so, again,
it can be conductive

for various different purposes.

And so what's going on here?

Were they
specifically choosing

certain types of rock

for technological reasons?

[Childress] When we look at
how the ancients were selecting

certain stones
that were magnetic

or had certain energies,

we wonder how they could know

about all of the-the properties
of these stones.

Are they getting
this information

from extraterrestrials?

[Narrator]
Extraterrestrials?

Is it possible that the ancient
people of Mesoamerica

were given instructions

to sculpt
these giant basalt heads

by alien visitors?

But if so, why?

As far as ancient astronaut
theorists are concerned,

the answer is simple:

they were intended to be used
for data storage.

In 2017, IBM made a huge
breakthrough in data storage.

They figured out how to store

201 gigabytes of data
on a square inch of tape.

That means a magnetic tape reel,

the size of
the palm of your hand,

can hold as much data
as you would have

in 330 laptops.

[Williams]
Mag tape, mag stripe tape,

is made out of, basically,

very, very tiny
magnetic particles.

And what they do is
they-they adhere them

to the back of a-a thin strip.

And the way it works is

the little metal filings,
which are very microscopic,

they would all align
in a certain pattern,

kind of like the grooves
on a record player.

And it would take
another piece of equipment,

similar to the one
that actually aligned them,

to interpret how
those particles are lined up.

And we still use it to this day
for backup data storage.

[Childress]
And so, once again,

we have to ask ourself
if these statues...

were in fact devices

that had recorded information.

And information could be
extracted from them.

Like a computer hard drive
or something like that.

[Nova Spivak] We've been
looking at these objects

primarily at
the macroscopic level.

What do they look like?

But maybe there's
information inside them,

encoded using nanotechnology.

Why is that likely?

Because we ourselves are
doing the same thing.

By trying to store information

for thousands
or millions of years,

you end up going to

the same physical materials
and solutions

that the hypothetical
ancient aliens may have also

figured out how to use.

Across the globe,

farmers have discovered
massive images in their crops.

These formations,
known as crop circles,

often appear overnight

and look like they were created
by an otherworldly force.

Curiously,
some researchers believe

that these complex patterns
contain hidden messages

that are encoded as sounds.

[Narrator] Yarnbury Castle.
Wiltshire, England.

July 26, 2020.

An intricate formation
of concentric circles,

featuring a number of
smaller semi-circles,

appears in a field of wheat.

While the design
may seem random,

some researchers believe
it contains a message

that can be both seen
and heard...

...because it is a perfect match

for what is known
as a cymatic pattern.

When we talk about
cymatic patterns,

we're talking about a frequency

that will create a image
that has a complexity to it.

So, specific frequencies
relate to specific patterns.

[Narrator]
The origins of cymatics

among human civilizations

can be traced back more than
ten centuries to West Africa.

There, tribal rituals

involved sprinkling
grains of sand

on the surface of drums.

Striking the drums created
specific audio tones,

causing the sand
to be instantly shaped

into distinct formations.

From the resulting formations
on the drum's surface,

tribal elders believed
it was possible

to predict future events.

[Childress] With cymatics,
you have these patterns

that are a visualization,
really,

of-of sound and vibration.

And physicists tell us

that the entire universe
comes down

to vibration and sound patterns,

and these patterns
that can be visualized.

[Narrator]
In 1787,

German physicist
and musician Ernst Chladni

offered a breakthrough
on the subject

when he published "Discoveries
in the Theory of Sound."

In the writing,
Chladni revealed

that specific tones
consistently create

the same visual pattern.

By applying sound vibrations to
metal plates covered in sand,

he identified
the images produced

by various frequencies.

[Henry] When we look at
so many crop circles,

they're consistent with what
we see in research on cymatics.

We find the same shapes

that are created
on Chladni plates.

We find the same shapes

that are created
in sound experiments.

So, there's
a very key connection

that is to be made here.

[Narrator]
But why would cymatic patterns

appear in crop circles?

Could extraterrestrials
be using audio frequencies

as a method of communication?

Ancient astronaut
theorists suggest

further clues can be found
by examining the teachings

found in ancient
Hindu religious texts

known as Vedas.

[Dominic Steavu]
The word "veda" means

"knowledge" in Sanskrit.

There is this
close association with

a special type of
wisdom or knowledge

that is transmitted
through the Vedas.

Now, originally, the Vedas
were revealed by the gods

to a certain class
of spiritual elect.

And they contain, again,
these primordial sounds

that are associated
with the creation

of the universe
and its proper functioning.

[Narrator]
In the Vedic texts, it is said

that the gods gave humankind
a visual guide to sacred sounds

in the form of elaborate
patterns called "mandalas."

Like Chladni's experiments,

the mandalas translate sound
into visual patterns,

but for a profound
and otherworldly purpose.

In Hinduism,
mandalas are considered to be

visual translations
of primordial sounds.

And these are the sounds

that gave rise to the universe,

and to the very nature
of reality.

They are divine,

they were uttered cosmically

by supernatural beings, by gods.

[Henry]
The Vedas tell us

that the gods taught humans
how to chant.

How to pray and to sing

in order to communicate
with the gods.

[Narrator]
The most powerful Hindu mantra

is the sound "Om,"

which is visually represented
by a simple circle

with a dot in the middle...

the fundamental element
of a mandala.

Incredibly,
when the "Om" frequency

is applied to a Chladni plate,

the exact same pattern emerges.

Higher-toned frequencies result
in more complex arrangements...

...that also identically match

the ancient mandala symbols.

[Collins]
Is it conceivable

that the writers of
the ancient Vedic texts

were given advanced knowledge

on how sound frequencies

can be converted
into visual patterns?

Some of the crop circle designs

are very clearly

reflections of sound.

Is it therefore possible

that what we are looking at
is sound signatures,

communication with
such higher intelligences?

[Narrator]
Many cultures around the world

believe it is possible
to commune with a higher realm

through ritualistic chanting,

singing, and prayer.

Like mandalas,
could crop circles contain

an otherworldly message
for humanity,

one that is based
on sacred sounds?

[Tsoukalos]
I certainly think that

crop circles are messages by...

other beings who are trying to

make contact with us,

or at least letting us know
they're there.

And the entire basis
of the universe is vibration,

and sound is vibration.

When we talk
about different ways

with which to communicate
with different civilizations,

scientists have proposed

that can be achieved
with sound frequencies.

[Childress]
What they're doing is

putting sound and vibration

into a communication device
of some sort,

but exactly what they're trying
to communicate to us

is the big question.

The idea that
an alien civilization

has left us hidden messages

may strike some
as sounding more like

science fiction than fact.

But in 2001, a crop circle
appeared in England

that many believe was sent

by extraterrestrials.

[Narrator] 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.

[Seth Shostack]
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.

It's 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.

[Nick 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.

It 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.

Was the so-called
"Arecibo reply" sent to Earth

by an alien civilization?

It's entirely possible.

But perhaps
the better question is,

are we ready to receive
the information contained

in these hidden messages
that are all around us?

One thing is clear:

whether they are
massive geoglyphs...

towering monoliths...

or elaborate crop circles...

once these extraordinary
sites are decoded,

we may be one step closer
to learning the truth

of our extraterrestrial past.

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