Original subtitles

Tonight, an ancient mechanical device

found on a 2,000-year-old shipwreck.

It's so complex that even the world's top scientists

can't figure it out.

It's like finding a jet plane in the tomb of King Tut.

But who actually made it?

Known as the Antikythera mechanism,

its origin and purpose are shrouded in secrecy.

ANDREW NICHOLS: The entire façade of it is covered

with writing that had never been seen previously.

How is it possible that this thing was made

over 2,000 years ago?

Now, we'll explore the top theories

surrounding this cryptic machine.

MICHAEL DENNIN: This is essentially a device

tracking the motions of the heavens.

What if it was made in the future,

and traveled back to the past?

Is there any evidence that aliens

built the Antikythera mechanism?

Can modern technology unlock its secrets?

JONATHAN SAYRE: Suddenly, it's capable of making

life and death decisions.

This is one of the greatest mechanical inventions

of all time.

What is the Antikythera mechanism?

Where did it come from?

And how does it work?

[music]

The Greek Isles, 1900.

A team of sponge divers are on their way home

from their fishing grounds off the coast of North Africa

when they're hit by a powerful storm.

[thunder crashing]

The sponge divers' boat swept into an area

off the island of Antikythera,

which is located north of Crete,

and south of the Greek mainland.

It is a rocky and barren island

with swift currents right off of its coast.

It's a very dangerous and treacherous area.

So, the group is incredibly lucky

that they don't wreck out there.

And after the storm settles down,

they decide to go back out and dive for sponges

one more time.

LAURENCE: Diver Elias Stadiatos goes first.

SAMI: He's underwater for about a minute,

and then he just jumps back into the boat terrified.

He's mumbling about men, women, horses in the deep.

LAURENCE: The team's captain,

Master Diver Demetrios el Kondos,

decides to go see for himself.

JONATHAN: El Kondos descends into the water,

and when he comes back up, he has an arm in his hands--

a bronze arm from a statue.

The quote-unquote "bodies" down there

were actually corroded statues from a shipwreck.

The team can't believe

what they found.

This ship is huge. It's 180 feet long,

even though only parts of the cargo

and the vessel still remain.

It's clearly very old,

and it lies at a depth of about 150 feet,

just to the north of Antikythera Island.

SAMI: It's an incredible find, but you have to remember,

it is the year 1900, and scuba diving

is in its infancy.

By that, I mean the suits are made out of canvas,

you've got copper helmets.

Scuba tanks, not a thing yet.

And many consider this to be the first major discovery

in underwater archaeology.

LAURENCE: Eventually, Greek authorities ask the divers

to help salvage items from the shipwreck.

AMORY: They start pulling out statuary,

and pottery, and silver and bronze coins, and jewelry.

It's an unimaginable bounty.

LAURENCE: As the treasure haul grows,

authorities begin to ask, what is this mysterious ship,

and where did it come from?

The coins and pottery on board appear to be Ancient Greek

and come from about anywhere from 80 to 50 B.C.

ANDREW: Because it's such a huge ship

and contains many high-end marvelous goods,

it's believed the ship was on its way to Rome

for a triumphal parade of Julius Caesar.

It does fit the timeline, since Julius Caesar ruled

until his death in 44 B.C.

LAURENCE: But not everything appears to be valuable.

JONATHAN: Amongst all these amazing artifacts,

they find this squarish piece of, you know,

corroded metal and dirt that looks like a rock.

It's about seven inches wide, and they bring it up with them,

but we're not really sure why they even looked twice at it.

Frankly, I'm surprised they even bothered

to bring it up from the sea floor.

SAMI: It isn't until a year later

that archaeologist Valerios Stais

is going through this pile

of some of the more unimportant artifacts that were found.

And he comes across this piece of corroded metal,

and at first doesn't think much of it,

until he looks inside, and he comes across

what appears to be a mechanical gear.

And he is confused, he is puzzled by this.

EVAGGELOS VALLIANATOS: Most scholars were convinced

that the gear technology

was invented primarily in Europe

maybe during the Renaissance or later.

So, we can imagine the astonishment and confusion

of Mr. Stais.

LAURENCE: The device is dubbed the Antikythera mechanism,

named for where it was found.

And it's much more complex than originally thought.

SAMI: Turns out that they brought up

about three main pieces of the mechanism,

with 82 separate fragments, many of which also had gears.

But it appears that this is only a small part of the machine.

And Stais is looking at all of this

and trying to figure out how it all goes together.

The fragments are not in great shape.

I mean, they're really,

really hard to get at.

They're covered in dirt, they're aged.

SAMI: Imagine trying to put this thing together.

It'd be like putting together a 3D puzzle

and all of the pieces are the exact same color.

Two-thirds of this thing are missing,

and the parts that we do have are covered in sediment

because they've been sitting at the bottom of the ocean

for 2,000 years.

LAURENCE: Faced with these challenges,

Stais ultimately gives up,

and no one attempts to decode the machine for decades.

Then in 1951, a British physicist

named Derek de Solla Price is studying the history

of scientific instruments of the ancient world,

and he becomes fascinated with the Antikythera mechanism.

He goes to Greece to see it in person.

He examines what he thinks are inscriptions on the device.

Now, that in and of itself is remarkable,

because it's pretty uncommon to see Greek writing

inscribed in metal.

SAMI: Many of the letters are rubbed off

or corroded beyond recognition.

But they do manage to translate one word,

which translates to "ray of the sun"

in Ancient Greek.

And then, there are other letters

which might be part of the word "Aphrodite."

LAURENCE: As Price manages to translate more of the text,

he develops a theory.

Most of the words that you could read

had to do something with the sky.

So, because of the gearing and the inscriptions,

this is what convinced Derek de Solla Price

that he was dealing with an astronomical computer.

Think about that, and really let it sink in.

This makes it a computer

that was built more than 2,000 years ago.

SAMI: Price sketches out a rendering of what he thinks

the original mechanism must have looked like.

We're talking about a box with dials on the outside.

You've got a hand-turned crank, and on the inside,

you've got a series of very complex gears

interlocking and interweaving with each other.

Price believes that this device actually calculates

the movement of the sun, of the moon,

and possibly the planets.

What the user would have to do, is they'd have to input,

for example, a date,

and then it would spit back out the information for you

as to where the sun, or the moon,

or potentially a planet was in the sky at that time.

That is just one definition of a computer, right?

You input information,

and then it will output data right back to you.

JONATHAN: The entire concept of that

is so far ahead of its time, like over 1,000 years ahead.

Having the math, the astronomy,

the technological prowess to create it,

it's just completely baffling.

LAURENCE: The discovery challenges everything

scientists thought they knew about the ancient world.

AMORY: There weren't astronomical

calendrical computers in Ancient Greece.

There were sundials.

That's what we thought was the height of their technology.

SAMI: The Ancient Greeks get a lot of credit

for being very advanced in the realms of places

like arts, philosophy, architecture.

But building a computer,

that's out of the realm of possibility.

This device should not have existed in 80 B.C.

MICHAEL: For this level of technology,

it's really when we start making mechanical clocks

in the 1300s that you finally get gears like this

on a regular basis.

And the first analog calculators,

we really don't see till the 1600s,

so it's like at least 1,500, 1,600 years

after this device was built.

SAMI: This is considered to be one of the greatest

mechanical inventions of all time.

And Price sums it up by saying that from all we know

of Hellenistic math and science,

we would think that a device like this could not exist.

LAURENCE: Price spends the next two decades

trying to uncover more answers.

Price becomes convinced in his study

that it is a planetary computer,

but he's never really able to figure out who built it,

or how it could have been built in that time period.

SAMI: So, Price works with what he has

and with what he can see, but remember,

there are still two-thirds of this device missing.

So, what are those components, what might they do,

and could they help to truly explain

what the purpose is behind the Antikythera mechanism?

Not only that, but the pieces that Price does have

are all fused together.

It's almost like a solid piece of stone.

It's very hard to discern what's going on inside.

LAURENCE: But it won't be for long.

LAURENCE: The mysterious Antikythera mechanism

stumps scientists for 10 decades.

How could something this complex date to Ancient Greece?

And what is its purpose?

British physicist Derek de Solla Price

thinks he knows.

JONATHAN: He believes that the device

is an astronomical computer

that was able to track

the heavenly bodies over time.

AMORY: But the technology that he's using

to study the mechanism

just isn't very advanced.

The best he can do

is an X-ray machine in the 1970s.

And those images are flattened.

You can't see the detail of the gears inside.

So, some of his conclusions are, by necessity, educated guesses.

LAURENCE: Then in 2002, the British Science Museum's

curator of mechanical engineering, Michael Wright,

applies new technology to the device.

Wright and his research partner

take radiographs of the machine

to fill in more of its functionality.

As opposed to just a flat two-dimensional scan,

these scans can focus on one plane at a time,

which allows for a more precise location

for each of these gears inside the machine.

After analyzing his scans,

Wright believed that this machine

was far more complex than what Price had originally asserted,

and additionally, there was a turntable on the inside of it

that rotated for each planet.

MICHAEL: One of the other cool things Wright finds

is a half-white, half-black marble

that he postulates can be used

to predict the phases of the moon.

This is confirmation of Price's theory

that this is essentially a device

tracking the motions of the heavens.

But now, we know more specifically

what it's tracking-- the moon, the sun,

and the several planets the Greeks were aware of.

LAURENCE: The question is, why was it used?

In 2013, a team at Cardiff University

performs even more advanced scans.

Led by astrophysicist Mike Edmunds

and mathematician Tony Freeth,

the approach that they take is two-pronged.

They use high-resolution surface scanning

to make their way through all of the corrosion

and the sediment that had built up on the device.

And they also use a computed X-ray tomography

to get closer looks on the inside.

What this will help them to do

is to create a highly detailed 3D image of the mechanism

for the very first time.

LAURENCE: The approach yields yet another breakthrough.

After they were able to finish their thousands of scans

of the 82 pieces, something truly amazing emerges,

and that is, they find writing.

EVAGGELOS: It's extremely difficult to read something

that is corroded.

But because they had more advanced technology

in their scanning of the device,

now you have hundreds,

hundreds of letters.

ANDREW: The entire façade of it is covered with writing

that had never been seen previously.

SAMI: Now, keep in mind that a lot of the parts

of the machine are still missing.

But the pieces that they're looking at

have about 3,400 pieces of text

that are written in Ancient Greek.

So, what they're really looking at

is a partial user's manual for the machine.

LAURENCE: The manual confirms the mechanism can track stars

and planets, but it also reveals something new.

There's a lower dial on the back of the device

that no one has been able to figure out yet.

But Freeth and his team, they think they have the answer,

because there are glyphs etched onto the segment

in the intervals of one, five, and six months.

And Freeth thinks that this is used

to predict the timing of eclipses.

Now, why is this important?

Because to the Ancient Greek,

predicting eclipses is predicting the future.

In the machine's instructions, there are references

to the size, and even to the colors of the eclipse.

And that's what keys Freeth in,

because eclipses don't have colors in nature.

But what's interesting here is that the colors

are what the Greeks used

for what they called astral divination.

LAURENCE: In Ancient Greece, astral divination,

or the reading of the stars, is a vital part of daily life.

The Greeks used this large-scale astrology

to determine the fortunes of entire countries

and civilizations.

Eclipses were omens, and the colors

determined whether they were good or bad omens.

They inherited this belief system from the Babylonians

who used to obsess over the sky and everything in it.

They would record whatever they saw

and the effects that it may have had on their lives.

For instance, on the day they set sail on a voyage,

any particular planet is in the sky

and the ship wrecks, the next time that planet

happens to appear, they won't send a ship out.

Now, we might call that superstition,

but to them that is very, very real.

SAMI: Now, imagine the value of being able

to have this information in advance.

Before the Antikythera mechanism,

if they had planted a bunch of crops,

and then an eclipse came and it was a bad omen,

and the crops die out, bad luck, right?

But with this device, they can now plan in advance,

because they know when the eclipses are coming.

ANDREW: This would allow them to plan far up ahead

when the best time to make offerings to the gods,

when to plan for big events,

and especially when to embark on campaigns

and to invade and launch wars.

LAURENCE: If this theory is correct,

the Antikythera mechanism is much more significant.

JONATHAN: Suddenly, it's capable of making

life and death decisions.

It's quite possible the device could operate the government

and make decisions about state craft.

LAURENCE: And as some historians are quick to point out,

they've only recovered a third of the machine.

Just imagine what the mechanism may have been tracking

or predicting in its full form.

Perhaps the weather, perhaps natural disasters.

Maybe even the rise and fall of entire dynasties

and civilizations, all laid out like clockwork.

LAURENCE: A map of the stars, or a way to predict the future?

Whatever its purpose,

the ancient Antikythera mechanism

is a technical marvel.

Scientists have been studying this device

for over 100 years now,

ever since it was first discovered

on that shipwreck in 1900.

And again, with something so enigmatic,

by all rights, something that should not exist,

you are dying to know, what was its original purpose?

What is it meant to do?

JONATHAN: But perhaps even more,

you want to know where it comes from,

what brilliant civilization

built this.

MICHAEL When we think about whoever created this device,

and compare 'em to other

creative geniuses,

like Leonardo da Vinci, Thomas Edison,

Albert Einstein,

clearly, this person is in the same class,

if not somewhat above them

because of the nature of the time they were in.

AMORY: Da Vinci conceived of a helicopter

400 years before a working one was built.

And then you have this society in 80 B.C.

that imagines this complex mechanical device,

the likes of which weren't seen for another 1,500 years.

And not only did they imagine it,

they built the thing.

So, that might have Leonardo beat.

SAMI: But who actually made it?

Was it really the Ancient Greeks?

I mean, the writing inscribed on it

would suggest that it comes from there,

but what workshop in Ancient Greece

has the skillset to actually build something like this?

And we know the great minds of Ancient Greece,

and it seems that almost nobody fits that bill.

Almost.

AMORY: Probably the only person in Ancient Greece

who comes to mind as maybe possessing

the constellation of skills needed to build

something like this is Archimedes.

ANDREW: Archimedes is an inventor,

a scientist, an engineer,

whose fame grew

and whose legend grew amongst those

who lived even soon after him.

AMORY: Around 50 B.C. the Roman statesman Cicero

actually writes about Archimedes owning a sphere

quote, "binding the disparate motions

of the seven heavenly bodies."

Could that have been the Antikythera mechanism?

LAURENCE: If Archimedes' workshop is the source,

the device would be even older than anticipated.

MICHAEL: Archimedes dies around 212 B.C.

and archaeologists and experts

thinks the device was made about 20 years

before the ship sank, which would have been 80 B.C.

That's almost 130 years after Archimedes died.

Does this rule out Archimedes? Not necessarily.

Maybe the device was already quite old

when it set out on this fateful journey.

LAURENCE: Recent evidence proves this could be possible.

Thanks to those 2013 scans,

we were able to calculate a day zero for the machine,

or the first date that it was calibrated,

when it started doing these really complex calculations

of astral positions.

And this date is way before 80 B.C.

Their best guess is about 204 B.C.,

which is around Archimedes' time.

So, maybe he started the device

and his workshop finished it off.

LAURENCE: The device's inscriptions

also may support this theory.

Many of these inscriptions have to do with datings

and calendars, which really helps us

narrow things down, because the Greeks

did not have a simple universal dating system.

JONATHAN: In 2008, researchers

at the Antikythera Mechanism Research Project

discovered that the names of the months on the device

are the same ones used for the Corinth colonies--

one of those colonies being Syracuse,

the home of Archimedes.

LAURENCE: But this theory is disputed

by NYU professor Alexander Jones in a 2017 book.

Jones considers the possibility of Archimedes' workshop,

but ultimately rejects it, because it doesn't line up

with where the mechanism was found,

which was on a voyage that was heading between Crete

and the Peloponnese.

Because we know for a fact that the ship was headed

out of the Aegean and into the Ionian Sea,

and Corinth and its colonies are nowhere on that path,

so the cargo couldn't have come from there.

LAURENCE: Around the same time, astrophysicist Mike Edmunds

also challenges the idea that Archimedes

or his team created the mechanism.

Edmunds heads the Antikythera Mechanism Research Project,

and he has something that a lot of the other researchers don't,

because he is an astrophysicist,

and he understands the mathematics

that the mechanism was built to calculate.

JONATHAN: The thing is, the mechanism

is extremely precise when it comes to position tracking

of heavenly bodies,

but only if you're standing in the right spot.

There are some limits, though, to the genius

of whoever built the Antikythera mechanism,

because it was designed around the belief

that Earth is at the center of the universe

and everything goes around us.

Now, of course, we know that's not true,

and we can calculate the position of a celestial body

no matter what vantage point we're coming from.

But back then, with the math that they had.

it's all relative.

LAURENCE: Based on Edmunds' calculations,

the Antikythera mechanism was built

at 35 degrees north latitude.

This is where the machine works perfectly.

Now, Archimedes lived up at about 37 degrees,

and up there, the machine would have worked okay,

but it would have drifted towards inaccuracy,

because it's about 150 miles too far north.

LAURENCE: And that finding opens up a new possibility.

AMORY: When you look at that line

that runs through 35 degrees latitude,

through the Eastern Mediterranean,

you realize there's not a whole lot there.

There's Crete, there's Cyprus, and that's about it.

And neither of those were hubs of technology, really.

LAURENCE: This leads some theorists to suggest

that the location the device was built vanished.

In 1996, author David Hatcher Childress

proposes the lost city of Atlantis

as the Antikythera mechanism's place of origin.

In a way, there is no more fitting home

for the mechanism than Atlantis.

Greek philosopher Plato describes it

as a powerful, advanced,

mechanically superior civilization

that was on a large island

and succumbed to natural disasters.

LAURENCE: For centuries, researchers have looked

for the remains of that lost city.

MICHAEL: When you start thinking about Atlantis,

if it existed-- and that's a big if--

there are a couple of top candidates

for where it might have been,

and one is off Santorini.

EVAGGELOS: What the modern Greece call Santorini,

the real name is Thera.

They had a volcano.

In 1650 B.C.E. it blew up

and destroyed two-thirds of the island.

And it triggered off these enormous earthquakes

and tsunamis that swallowed up a lot of Santorini

and also impacted Crete, and possibly any other islands

that sat in between the two.

SAMI: Now, I know most people might think Atlantis,

it's a place of fiction, right?

But there actually was a real-life civilization

that was submerged by water,

and they were called the Minoans.

And many historians think that the Minoan civilization

actually inspired the story of Atlantis.

And the location actually lines up with the origins

of the Antikythera mechanism--

a now-missing island just north of Crete

that sits at 35 degrees latitude.

LAURENCE: But not everyone is convinced.

One of the challenges with the Atlantis theory,

even if Atlantis existed, is the timing.

It would have been long gone by 80 B.C.

If this is a relic from Atlantis,

it would have been quite old by the time

you load it onto the ship.

Now, it's not completely impossible,

because after all, it's a partial thing

that survived 2,000 years at the bottom of the sea.

It might be even older than that.

But this one's gonna be really difficult to prove.

Scientists have worked for over a century to understand

the Antikythera mechanism, yet one key question remains.

How could this device from 80 B.C.

be so far ahead of its time?

In 1997, one author proposes a shocking idea.

The machine may not be as old as we think.

CAROLINE CORY: Pretty much everyone who has studied

or even looked at or read

about the mechanism would say,

how is it possible that this thing

was made over 2,000 years ago?

JONATHAN: That is, until author J.H. Brennan

presents a novel new approach to the problem.

What if it wasn't made

2,000 years ago?

What if it was made in the future

and traveled back to the past?

AMORY: In his book "Time Travel: A New Perspective,"

Brennan asks, was the Antikythera mechanism

carried to Ancient Crete from the future?

It sounds preposterous,

but does it sound any more preposterous

than thinking that the Ancient Greeks

made this device? Some would say no.

JONATHAN: Its sophisticated understanding of astronomy,

its mathematical prowess,

as well as its mechanical engineering genius--

we have no other evidence that this type of skill

ever existed in 80 B.C. other than this device.

We have no other device that has

a similar level of technology.

There's no evidence for anything else

like this mechanism in 80 B.C.

AMORY: Even pioneering researcher Derek de Solla Price

says that finding this device on a Roman shipwreck

is like finding a jet plane in the tomb of King Tut.

Just the fact that it's a clockwork

gear-based mechanism is something

we didn't think existed in Ancient Greece.

One of the gears on the Antikythera mechanism

is what's called a differential gear.

ANDREW: A differential gear is a gear

in which the cogs are of different sizes.

So, you have a large gear

and a smaller gear.

The large gear has to spin

at a more rapid rate to keep up

with the smaller gear.

MICHAEL: So, a common differential gear

exists in your car, because when you make a turn,

the outer wheel has to spin faster than the inner wheel.

SAMI: The differential gear in the Antikythera mechanism

is used to determine the angle between the sun, the moon,

and the phases of the moon,

and there it is, in 80 B.C.,

in this machine.

The next time that we see a differential gear

used in a device is in the year 1720

in a clock made by Joseph Williamson.

And it is not in common use until the early 1800s.

CAROLINE: Maybe now Brennan's time travel idea

isn't so far-fetched.

If the mechanism features technology

from 1,800 years into the future,

how do you reconcile that?

LAURENCE: Proponents of this theory

also point to the fact that nothing else like it exists.

Breakthroughs in the history of science

are generally developed over time.

When you look at the history of something

like the printing press, or a telephone,

or an automobile, there are precedents.

There are partial steps in the development of the device

that get it to where it is today.

We didn't just suddenly have a Corvette.

There were a lot of rudimentary attempts

at a vehicle that got us to the Corvette.

JONATHAN: But the mechanism has no precedents

in ancient times.

We have found nothing else like this, not even close.

So, you have to ask, where are the other devices?

Why haven't we found any other mechanisms

that could do even a fraction of what this one does?

MICHAEL: When we think about clockworks,

and you wanna look at its development

from rudimentary clockwork to more advanced,

you're really gonna be looking at the period

just before the Renaissance, that's when it started.

You're not gonna be looking at Ancient Greece.

AMORY: For all these reasons, the idea

that the Antikythera mechanism traveled through time

does have some supporters.

But then there are other theorists

who are even more out there,

who say the Antikythera mechanism

didn't just time travel,

it is the time machine.

MICHAEL: So, on the front of the device,

you have the positions of various objects--

the sun, the moon, and the planets.

You then have a crank that you use

to rotate to a particular date

that then puts everything in the position

where they're gonna be in the sky.

So, therefore you have a device that is calculating

both space and time.

SAMI: When physicists like Albert Einstein

and Stephen Hawking talk about time travel,

the question becomes whether or not space and time

can fold in on itself to allow a person

to jump in between time periods.

So, those inputs on the Antikythera mechanism,

could they be coordinates for a journey

through space-time?

JONATHAN: The mechanism could literally be an atlas

to the cosmos in four dimensions,

including time.

It's a map to get you to your destination.

LAURENCE: But with only one-third

of the Antikythera mechanism to examine,

its additional functions or its possible purpose

can't be fully determined.

Nothing of what we currently have is a time machine,

let's just be clear about that.

But could the mechanism's missing parts

help power a journey through time?

It makes for a fun story.

The very first time traveler finishes their prototype.

They decide they want to encode the instructions

in Ancient Greek, because they've long admired

the society for its well-known wisdom,

so much so, that that's actually where they wanna go

on their first destination,

so they go back to Ancient Greek in the time machine.

They're there, some tragedy befalls them--

the shipwreck-- and poof.

The only Antikythera mechanism is now stuck in 80 B.C.

LAURENCE: In 1968, one influential author

suggests he knows the secret to the Antikythera mechanism.

AMORY: In his 1968 book "Chariots of the Gods?",

Erich Von Daniken questions numerous ancient technologies

which he believes were too advanced to have been created

by the humans in those respective eras.

So, these are things like the pyramids,

and Machu Picchu, Stonehenge, and the Antikythera mechanism.

CAROLINE: According to von Daniken,

the reason is clear.

These things were not created

by humans, they were made

by highly intelligent extraterrestrials.

JONATHAN: The theory is definitely out there,

but it attracts a lot of believers.

If this machine is beyond human knowledge,

what other option do we have?

AMORY: Von Daniken believes that in the distant past,

extraterrestrials land on Earth, they make contact with humans.

They share their knowledge and wanna help

advance scientific progress.

And in the places where this happens,

we see these unexplainable advancements,

like in Ancient Egypt, or in this case, Ancient Greece.

MICHAEL: The theory is that this is extraterrestrial technology

given to humans that's based on their understanding

of tracking the stars and the planets

so that they can help humans better understand

the universe around them.

According to von Daniken, the reason

you have Ancient Greek language

written on the device

is that either the extraterrestrials

built it for them and then translated the instructions

into Ancient Greek, or taught them how to build the device,

and the Greeks themselves put the instructions on it.

LAURENCE: In 1999, von Daniken publishes

"Odyssey of the Gods," in which he suggests

that Ancient Greece was once a nexus of alien activity.

Von Daniken sees evidence of this all around.

The Antikythera mechanism, the advanced political structure

and civilization that they build,

even the stories that they tell about their gods.

CAROLINE: Extraterrestrials capable of traveling

distant galaxies would look like gods

to ancient humans.

Von Daniken believes these visitors

are an inspiration for the Greek gods--

Zeus, Apollo, Aphrodite,

and the other residents of Mount Olympus.

JONATHAN: Another thing that comes up

in Greek legends is flying.

Gods fly, chariots fly.

This is unusual in a society

where they've never seen anything that flies

other than birds and insects.

As we know, there are no flying vehicles

in Ancient Greece, but maybe some came to visit.

AMORY: Is there any evidence that aliens

visited these ancient cultures?

Not exactly. But the Greeks and Romans

observed and recorded some strange happenings in the sky,

and some of those accounts are pretty curious.

LAURENCE: In 2007, Goddard Institute astrophysicist

Richard Stothers publishes a report

on unexplained aerial phenomena in the ancient world.

MICHAEL: Stothers analyzes these texts

from Ancient Greece and Rome, and finds a ton

of unusual phenomena in the skies at that time.

Now, some of it can be explained as meteors and asteroids,

but a lot of it remains unexplained.

CAROLINE: In 65 A.D., historian Josephus

in his "History of the Wars" records an event in Judea

that can only be described as a battle in the sky,

with chariots and troops of soldiers in armor

shooting fire at each other.

ANDREW: This event had many witnesses

and has led some people to argue

that this was an alien encounter.

JONATHAN: Stothers compares these accounts

to modern UFO reports, which as we know,

our military has begun declassifying.

AMORY: Other ancient records describe objects in the sky

that are disc-shaped, and metallic in texture,

and have soundless movement, and are able to hover.

And this actually sounds a lot like modern UFO sightings.

So, it doesn't prove that aliens visited Ancient Greeks,

but it's interesting.

LAURENCE: Could this origin hint at the true purpose

of the Antikythera mechanism?

AMORY: So, let's assume just for a minute

that it is alien technology.

Well, then what was it used for?

I mean, why give the Greeks this machine?

CAROLINE: Von Daniken suggests that due to its portable size,

it was probably made as a navigation device.

It would have been easily carried

and mounted on a ship.

JONATHAN: According to von Daniken, the aliens

were hoping that the humans would advance from ships at sea

to ships in the sky, or spaceships.

This device was ultimately designed

to navigate our solar system, not just the Mediterranean.

LAURENCE: Some speculate the machine

might be capable of even more.

Don't forget all the missing parts.

While the pieces we have help track the planets

closest to Earth, alien theorists

think that the full device might have been used

to track aliens' home world,

or other navigational aids that might have helped us

get from here to there.

JONATHAN: Alien theorists also speculate

that there might be a communications component

within the missing section.

Maybe it doesn't just track the aliens' home,

maybe it is a way of sending messages.

SAMI: Let me be very clear.

Was this incredibly precise machine

made by highly intelligent extraterrestrials?

No, probably not.

I mean, probably not.

JONATHAN: But I think it is absolutely amazing

how the mechanism inspires wonderment

in everyone who comes across it.

How did it get here, where did it come from?

The stories that people come up with

for this thing are incredible.

The possibilities are endless.

LAURENCE: In 2021, a team led by Dr. Tony Freeth

completes a significant breakthrough--

a working model of the Antikythera mechanism.

MICHAEL: Dating back to one of the original researchers,

Derek de Solla Price, many people have tried

to recreate the mechanism,

or partial versions

of the mechanism.

JONATHAN: But this one is different.

It includes every gear, every inscription,

and every functionality.

It even includes the wooden case.

Everything we know,

every piece we've found,

all put together

in working order.

AMORY: It doesn't reveal any additional functions,

but it's definitely a useful tool to have

to see this all come together.

And it could lead to future discoveries.

ANDREW: Freeth building this model

has an unintended consequence.

It leads many people to argue

that the mechanism

never worked at all,

and all the theories around its possible uses

are in fact wrong.

Over the years, many have questioned

whether the Antikythera mechanism ever worked.

In 1980, the American scientist

and Nobel Prize winner Richard Feynman goes to Greece,

and he sees the Antikythera mechanism for himself in Athens.

And he wonders whether it could have functioned.

JONATHAN: Freeth's model works.

However, we have no proof that the original mechanism

ever actually did.

And Freeth takes some liberties

in assuming how certain gears fit

and how they may have fit together.

With the benefit of modern technology

and the ability to work backwards,

he can kind of guesstimate and put the thing together

the way he feels it should work.

MICHAEL: This does not mean it's accurate to the original,

and Freeth makes no such claim.

It's not meant to be taken

as a literal reconstruction of the mechanism.

He points out, however, that it does prove

that something with this functionality

could fit in a box that size.

LAURENCE: But is there any evidence the device

ever actually functioned?

AMORY: Theorists quickly point to the fact

that it took us more than 120 years

since the object was found in 1900

to build a replica that works the same way,

and that's with hundreds of top scientists studying it

and the benefit of modern technology.

This just wouldn't have been possible in 80 B.C.

ANDREW: People point out that Freeth's model

does not look exactly like the mechanism,

which is currently a mass lump with no moving parts.

JONATHAN: The mechanism is a few hunks of metal and rock

with a few gears sticking out of it,

looking more like something from a Frankenstein movie

or a class project than a computer.

LAURENCE: It wouldn't be the first time

experts were fooled.

SAMI: In the 18th century, a man named Johann Kempelen de Pazmand

creates a clockwork robotic chess player

that becomes known

as the Mechanical Turk.

The machine has a life-size human head and torso

with arms that are resting on a cabinet.

And on the cabinet is a chess board,

and human beings come up and play chess

against this machine, and the machine wins.

The Turk makes its official debut

in 1770 in Schönbrunn Palace,

which is the summer residence of Austrian rulers.

Before it starts to play, the audience is invited

to come up and check the machine to see that it is actually real,

that there are no strings moving the arms,

or no devices of any kind allowing it to move.

But it all checks out, and people,

when they're playing the Mechanical Turk,

try to perform some illegal moves,

but the machine will start to shake its head and say "No,"

as if it's recognizing that that move is not allowed.

It's really incredible.

LAURENCE: The Mechanical Turk becomes a sensation

across Europe.

AMORY: It tours European capitals in 1783,

stopping at Versailles and playing

all of the best chess players in the world.

It plays Benjamin Franklin, Napoleon Bonaparte,

the King of Prussia-- brilliant minds

who all marvel at this chess-playing automaton.

LAURENCE: But in 1834, a series of articles

reveals the device to be fraudulent.

MICHAEL: For 60 years it fools everyone,

but it turns out that it's all an illusion

with a human chess master inside the cabinet

playing and manipulating the machine.

JONATHAN: But even though the Turk doesn't work

without a human operator, it is still a brilliant design.

The device is put on display in Philadelphia in a museum

until it burns down in 1854.

People celebrate it as a cunning piece of clockwork,

regardless of the fact it didn't automatically play chess.

LAURENCE: Can the same be said of the Antikythera mechanism?

AMORY: The parallels are clear.

The Antikythera mechanism could be the original

Mechanical Turk, and maybe it was a showpiece,

a marvelous clockwork housed inside of a statue

that appeared to track the heavens

through time automatically,

but it wasn't actually automatic.

Inside the statue there was an operator

making it all work.

LAURENCE: Despite the questions it raises,

most historians still believe

the Antikythera mechanism is genuine.

We know the Greeks were big fans of amusements and entertainment.

But if that's the case for this device,

why engrave it all over with the detailed instructions?

What purpose does that serve an audience?

I don't think it was meant to be gawked at

and for entertainment, it was meant to be used.

AMORY: And if it didn't work, why was it on a ship

with all of these other marvelous treasures

bound for someone potentially as important as Julius Caesar?

I think they thought this was a really valuable object.

SAMI: Dozens of academics have dedicated their lives

to studying this thing, and it has rewritten

the history books to show what mankind is capable of.

Our species is incredible.

We may not know what the Antikythera mechanism

actually did, but we can take pride in the fact

that somebody was brilliant enough

to create this thing over two millennia ago.

And hopefully someday soon, there will be somebody

brilliant enough to solve its mysteries.

Recovery efforts continue to this day

at the site of the Antikythera shipwreck.

In 2017, an additional gear was recovered.

Scientists are now working to determine its function.

Perhaps new discoveries will unlock the machine's secrets,

or they may simply leave us with more unanswered questions.

I'm Laurence Fishburne.

Thank you for watching "History's Greatest Mysteries."