All language subtitles for The.Universe.S09E06.Roman.Engineering.WEBRip.x264-ION10

(male narrator)
Ancient sites

with hidden powers

to turn light
from outer space

into spectacular
special effects.

Did Roman emperors harness
the power of the universe

to awe and terrify
the people of Rome?

We uncover
the last, great mysteries

of the ancient world's
greatest empire.

Ancient mysteries,

shrouded in the shadows of time.

Now, can they finally
be solved

by looking to the heavens?

The truth is up there,

hidden among the stars,

in a place we call...

The Universe.

The ancient monuments of Rome.

Millions of tourists
photograph them every year.

But is there more to them
than people guess?

There's new evidence

that these ruins
were once machines,

designed by Rome's emperors

to connect their power
with the sun.

The evidence may be here,

in a temple in
the heart of Rome

that has survived
nearly intact

for almost 2,000 years.

The Pantheon.

World famous for
its concrete dome

and the 27-foot hole
in its center

called the "oculus,"
or eye.

Sunlight flows in from
almost 15 stories

above the Pantheon's
marble floor,

providing the main room's

only source of natural light.

But is there also something
far more mysterious going on?

Professor Robert Hannah
thinks there is.

Now, I'd been going
into the Pantheon

how many times
over 20 or 30 years

and not even thought
of this.

But some years ago,
I was working

on aspects of Roman time,

and I came across the idea
that, in the Pantheon,

what we seem to have
is a monument

that is able to capture the sun

by subtle means
in the decoration

and in the architecture.

(narrator)
As evidence for
his startling theory,

Hannah points to the way
the oculus focuses sunlight

on different parts of
the Pantheon

at different times

on the longest and shortest
days of the year,

the summer and winter
solstices.

And especially on two days

that to the ancients symbolized
a great cosmic balance.

The Equinoxes.

Roughly speaking,
the Equinox is a time

when day and night
balance each other.

12 hours of day,
12 hours of night.

(Johnson)
The tilt of the Earth's axis

means that different parts
of our globe

are closer to or
further away from the sun

as we go around the sun.

We have two equinoxes
because we have

two positions when
the tilt of the Earth

is neither toward
or away from the sun,

twice a year,
six months apart.

So roughly in
the third week of March

and the third week of September,

we have equal day
and equal night.

(narrator)
Are these solar movements marked

inside the Pantheon?

The equinoxes are
halfway through the cycle

of the sun in
the course of the year.

At noon,
halfway through the day,

the sunbeam strikes
the point halfway up

the interior of the building,

where the cylindrical wall

meets the base of the dome.

That has to be more
than coincidence.

All of it is midway points
in time and space.

(narrator)
But was this really a part
of the original design?

Just because you see
an astronomical alignment today

doesn't mean it existed
2,000 years ago.

It's possible that when
the Pantheon was built

around the year 125,

the ancient sky would've
lined up

differently with the building.

Hannah's ideas are put
to the test

at Indiana's Ball State
University.

The members of the virtual
reality team at IDIA Lab

are experts in examining
astrological alignments

at ancient sites,

including Stonehenge.

Based on the latest research

and archeological findings,

IDIA Lab recreates with pixels

what the Romans built
with concrete and bronze.

The Lab's computers
can then simulate

the exact location of the sun

for any date in time

over a period of 20,000 years.

Neil, let's go ahead
and just kind of

take a 360 degree pan.

Look at the dome,
also the central oculus.

Let's go over to the celestial
simulation interface.

(narrator)
Hannah's theory could stand
or fall

because of one cosmic fact.

Over time, the dates
of the equinoxes change.

(Filippenko)
The day is not exactly
24 hours long.

An exact 24 hour day
would be

86,400 seconds long.

But right now,
in fact,

the day is 86,400.002
seconds long.

Now, over the centuries,
that actually adds up.

(Fillwalk)
The dates of the equinox
do change over time.

If we're talking about
back to the Roman era,

you may find that
they're several days off.

(narrator)
Does that sink Hannah's theory?

Let's go ahead and
look at the equinox.

(narrator)
IDIA Labs spins back the clock

to the era when
the Pantheon was built

and dials in the date
of the equinox.

The effect is clear
and stunning.

At the equinox moments,
vernal and autumnal equinox,

we see the sun disc
being perforated by

the Coronus element.

(narrator)
It turns out that the sheer size
of the Pantheon,

with its massive circle
of light,

counteracts any slippage
in the timing of the equinoxes.

It was an intentional effect

and it was designed to last
for millennia.

But if the Pantheon was designed
to track solar events

like equinoxes, then how,
using only technology

available to the ancients,

do you design a building
that will focus the sun

where you want it
at certain times of the year?

First, you take a year
to plot out

the sun's apparent path

to cross the sky.

From rising and setting

to solstices and equinoxes.

Once you know
where the sun will be,

you can set up a device
to mark its movements.

The sundial,

one of the first ways
the ancients brought

the power of the universe
down to Earth.

The sundial tells time
with a blade

that blocks the light
and casts a shadow.

(Kaku)
Take a look at the shadow
of a sundial.

As the sun moves,
it traces out

a motion of the shadow.

You divide it into 12 pieces,

and that becomes
the hours of the day.

(narrator)
But does that mean that

the Pantheon is
a 2,000 year-old sundial?

Some scholars challenge
the idea,

saying that the Pantheon isn't
built like an ordinary sundial

with a blade.

A historian had written up
an article, said,

"It doesn't work."

And I thought, "You're using the
wrong type of sundial."

(narrator)
The answer may lie in a
different kind of Roman sundial,

a hemicyclium,

essentially a stone bowl

with a hole
angled towards the sun.

This is a mock-up
of a hemicyclium.

In ancient Roman times,
it would've been made of stone.

Here is the noon timeline

and the hours of the day.

And if you can see it,

a beam of sunlight is projected
on the interior.

With this kind of sundial,
you're marking time

not with a shadow,
but with sunlight.

(narrator)
So, the Pantheon is like
an inverted hemicyclium.

You're inside a sundial,
where time is told by light.

As the sun moves around,
the light from the oculus

also moves around
the building.

It's an incredible feat
of architecture.

(narrator)
But did the Pantheon have
a higher purpose

than simply marking time?

Is a deeper meaning revealed

on a certain day in spring?

A colleague of mine,
Julie O'Malley,

discovered that on
the 21st of April

at noon,

if you stand in the doorway
of the Pantheon,

you are bathed in
that beam of light.

(narrator)
But why April 21st?

It's nowhere near the equinoxes
or other major solar events.

And why light up the doors?

Unless someone is
coming through.

21st of April, so what?

Well, that's a very ancient
festival.

It is the traditional founding
day of the city of Rome.

So, April the 21st
is a big deal.

(narrator)
How does all of this connect
with the sun

lighting up the doors
of the Pantheon?

The team at IDIA Lab
has the answer.

It all goes back to the man
who oversaw

the Pantheon's construction,

the emperor Hadrian.

IDIA Lab confirms a precise
midday alignment

during Hadrian's reign.

So, on April 21st,
the sun lights up

the entrance to the Pantheon

perfectly,
like a theater spotlight.

And so, if somebody
were to come in,

let's say the emperor,
Emperor Hadrian,

they'd walk in and
they'd be illuminated

by the light on that day,

and that date happens to be
the birthday of Rome.

Marking the entrance
of the emperor,

coming in style, announcing,

"Here I am!"

(narrator)
If Hadrian did turn the sun into
his personal spotlight,

it would be the ultimate
ancient special effect.

But it wasn't just for show.

By creating a machine to
capture and control the sun,

Hadrian was demonstrating
his power,

not just over Rome,

but over the heavens.

How can we be sure
Hadrian built the Pantheon

so he could command the sun?

Because emperors before him
also built monuments

to capture the sun
for their own glory.

Including one
that caught the sun

on the anniversary of
Rome's most infamous murder.

(narrator)
To scientists,
the sun is our nearest star.

A ball of hydrogen and helium,

330,000 times the mass
of the Earth,

with a core temperature
of 27 million degrees.

But to the ancient Romans,

the sun was a god.

(Kaku)
First of all,
it's the giver of life.

Without the warmth
of the sun,

we're plunged in darkness
and we freeze to death.

Second of all, it is
the dominant object

in the heavens.

(narrator)
Romans worshipped the Greek gods

Apollo and Helios,

both of whom were often shown
driving the sun.

From our vantage point
here on Earth, it appears

that the sun travels
across the sky in its path,

leading to
the ancient belief

that it was carried by gods
and their chariots.

(narrator)
The Romans also had
their own sun god,

Sol.

So it makes sense that
the emperor Hadrian

would've constructed
his Pantheon

to align with the sun.

But how do we know
these alignments

were intentional?

One form of proof would be
to find evidence

that Hadrian was building
on a tradition

established by earlier emperors.

Could that evidence be found

just over a mile north
of the Pantheon?

This is the Ara Pacis,

or "Altar of Peace."

Built by Rome's first emperor,

Augustus Caesar, in 10 B.C.

The Altar of Peace
represented the end

of a century of civil war.

So, building an altar of peace

is a major propaganda exercise.

(narrator)
Directly opposite the altar,

Augustus set up a 600-year old,

71-foot tall,

red granite obelisk,

transported from
the conquered nation of Egypt

and dedicated to the sun god.

But why use an Egyptian monument
in Rome?

The Romans knew that
in ancient Egypt,

the obelisk was a symbol
of a ray of the sun.

(narrator)
The Egyptians used obelisks
as billboards

to advertise the achievements
of various pharaohs.

But Augustus repurposed
this centuries-old obelisk

as something new,

the giant blade of a sundial.

I think that we definitely
should think of

these ancient tools
as technology.

They may not be electronic,
per se,

but they were certainly tools
to learn about the heavens.

(narrator)
Augustus created
a giant calendar

that marked
the days and the seasons.

But did Augustus go beyond this,

making this obelisk
interact with the sun

in even more dramatic ways?

It's a challenging question
to answer.

Unlike the Pantheon, this site
has not remained intact.

The Altar of Peace has been
relocated to a museum.

The obelisk was toppled
in an earthquake,

restored in the 18th century,

and moved.

It stands today several blocks
from its original location.

So the ancient alignment
has been destroyed,

and it's up to the virtual
reality team

at Ball State University's
IDIA Lab

to make the past live again.

With onsite data surveys,

GPS information,

and NASA observations,

they recreate
the original positions

to see what special effects

the altar and obelisk
may have created

with the sun.

In doing so, IDIA Lab discovers
something astonishing.

On one special day,

the obelisk's shadow would've
climbed the marble stairs,

moved through the altar itself

and continued out the other end,

penetrating the building.

It pierced the heart of
the altar like a knife

on March 15th,
the Ides of March.

The date in 44 B.C.
when knives pierced

the heart of Augustus's
predecessor,

Julius Caesar.

Even more amazing,

the shadow of the obelisk

cut through a rectangle of light

created by the opening
of the altar.

Did the light represent
Caesar's body?

Or possibly
another object from the heavens?

In 44 B.C.,

a few months after
Caesar's assassination,

a comet appears in the skies
over Rome.

Augustus,
Julius Caesar's adopted heir,

promotes the idea that
the comet is Caesar's soul

transformed into a god.

Augustus very cleverly
made Julius Caesar a god,

and therefore himself
son of a god.

No one had ever been
that before.

(narrator)
So perhaps the light bisected
by the shadow

was intended to represent
Caesar's comet.

But did Augustus symbolize
his own godly power

with something more enduring?

Not a comet that fades away,

but the eternal sun.

The sun is dependable,
it's reliable, it's glorious.

And you just look outside
and there it is.

(narrator)
With the altar and obelisk,

Augustus used the sun
and stones to tell a story

of his own power.

He reminded Romans
of Julius Caesar's godhood

and his own.

And by raising an obelisk
to track the sun,

Augustus told the world
that the heavens

were under imperial control.

So when Hadrian built
his Pantheon

almost 150 years later,

he built on a Roman tradition

of aligning monuments
with the sun

to create dramatic
special effects.

Instead of an outdoor monument
that used a shadow,

Hadrian built a dome

that turned the sun itself
into a spotlight

for the emperor.

But was Hadrian also inspired
by another emperor,

who many historians called mad?

New evidence may have solved
this ancient mystery.

(narrator)
To the ancients,

the wider universe was
largely unknowable.

But they understood
the importance of the sun,

and Roman emperors aligned
their structures

to convey their control
over our nearest star.

The emperor Hadrian may have
designed the Pantheon

so he could make
a propaganda appearance

bathed in sunlight
on Rome's birthday.

But was Hadrian inspired by

the most notorious emperor
of them all,

Nero?

(Markley)
Nero was the man in charge

while Rome's burning.

He was the one who burned
Christian martyrs.

So he goes down in history as
a bit of a monster.

(narrator)
But did this man,
whom history calls a monster,

consider himself a god?

By the time you get to Nero,

you start to question whether

the living emperor is a god.

In particularly
the sun god, Sol.

Nero adopts the radiate crown
of the sun.

We see it in his coins.

(narrator)
Some say Nero even turned
himself into the sun god

in the form of a Colossus

over 100 feet tall.

But Nero's earthly glory
didn't last.

He was deposed

and driven to suicide.

With the hated emperor dead,

the Romans had to decide
what to do about his Colossus.

There is an attempt
to remove

the association with Nero

and simply say it is
a statue of the sun god.

The statue is physically moved
from its spot

slightly over to
an amphitheatre.

(narrator)
The Colossus gave the
amphitheatre the nickname

it's kept for 2,000 years,

the Colosseum.

As for the Colossus itself...

The Colossus is lost.

We have rediscovered
parts of its base,

but the statue itself
has disappeared.

(narrator)
Most of ancient Rome's
sun-related structures

have vanished or lie in ruins,

with connections that can only
be recreated in virtual reality.

But parts of Rome's obsession
with tracking the sun

are very much alive.

Today, many people feel like
slaves to their schedules.

Everything from clocks to phones
tells us we're running late.

Over 2,000 years ago,

the ancients got stressed
in the same way

about sundials.

It seemed like the government

was setting these devices up
everywhere

to regulate the heavens
and people's lives.

When sundials first came in,
they are a newfangled machine.

And the people are
complaining about

the tyranny of the sundial.

The way the joke goes is that,

in the past you used to know
when you could have

your dinner or lunch because
your stomach told you.

Now we have to wait until
the sundial tells us.

(narrator)
While ordinary people had to
obey the sundial,

the emperors used
sundial technology

to celebrate their own power.

One amazing example survives

in the ruins of
one of Nero's palaces.

The Octagonal Room,

an eight-sided chamber
open to the sky.

The dome and oculus probably
inspired the Pantheon's dome

two generations later.

When you walk into
Nero's octagonal room,

it really is quite striking
that you get this

distinction between
strong light and strong dark.

And you're drawn immediately
to the idea of

"that sunlight matters."

(narrator)
Recent calculations reveal

that Nero's octagonal room
and oculus

were perfectly designed
to throw sunlight

on the main doorway,
on the anniversaries

of key moments in
the emperor's career.

The 5th of March was when
Nero became Pontifex Maximus,

the chief priest,
the person in charge

of the calendar and of time.

And the 13th of October,

the date of his
accession as emperor.

(narrator)
To celebrate his becoming
the most powerful man in Rome,

Nero captured the rays of the
most powerful star in the sky.

It's easy enough to imagine him

standing within the doorway,
bathed in sunlight,

suitably dressed and attired

and capturing the sun
in that way.

(narrator)
If Nero made the sun
seem to obey him,

this is tantalizing evidence

that he inspired Hadrian

to create an even greater
solar spectacle

with the much larger Pantheon.

But Hadrian didn't stop there.

He created more
solar special effects.

Not just in the Pantheon,

but in his own private city,

where today,
at the summer solstice,

the setting sun lights up
an empty alcove

in a ruined temple.

What sacred object once
stood here?

It's a mystery that we may
have finally solved.

(narrator)
Rome's emperors took the ancient
worship of the sun

and did something new.

Using building and monuments

to create the illusion that
they controlled the sun.

In the Pantheon, Hadrian
may have used

astronomy and architecture

to turn the sun into
his personal spotlight,

reinforcing public perception

of his imperial power.

But new evidence suggests

Hadrian built other
solar-connected structures,

for more mysterious,
private purposes.

He built them here,
on 300 acres outside Rome.

It's called Hadrian's Villa,

but it was much more than that.

(Markley)
We're here at the Getty Villa
in Malibu,

and it's based on
the private residence

of a very wealthy Roman.

Hadrian's Villa,
that's 20 times bigger!

That's the kind of residence

that only an emperor
could afford.

It was Hadrian's
Rome away from Rome.

(narrator)
Hadrian had complete control
over his villa's architecture.

And as our virtual reality
investigators

at Ball State University's
IDIA Lab reveal,

he created dramatic
solar effects

in places throughout
the complex.

This is the axis
that the sun

would travel
and send light down

on summer solstice
sunset.

(narrator)
One temple,
called the Roccabruna,

lines up with a structure
called the Accademia,

or "Academy,"
and both buildings line up

with the summer solstice.

(Fillwalk)
On that summer solstice event,

the sunset rays of light

would penetrate the upper
temple door of Roccabruna,

all along the pathway

and go down into
the Accademia site itself.

During the spring, the sun
appears progressively

higher in the sky
each consecutive day.

Until it's at its highest point.

That's when the Earth is
tilted toward the sun

the most that it ever is.

That's the summer solstice.

The Earth is not vertical
with regards

to the plane of
the solar system.

It's tilted roughly 23 degrees.

As the axis tilts away
from the sun,

the northern hemisphere
gets less sunlight.

It is the shortest day
of the year.

It is the winter solstice.

On the left hand, we see that
the axis points toward the sun.

The northern hemisphere gets
more sunlight,

and this is roughly
the summer solstice,

the longest day of the year.

(narrator)
But the Roccabruna does more

than just line up with
the solstices.

In the 1980s,

architects Robert Mangurian
and Mary-Ann Ray

discovered an even more
mysterious effect inside.

On the summer solstice,

the light of the setting sun

fills an empty alcove

while a conduit

focuses a blade of sunlight

just above the space.

IDIA Lab's calculations show

that the effect was even more
impressive in Hadrian's time.

The summer solstice light comes
through and creates

a very precise,
almost sort-of gunsight

kind of event on
the back of the temple ceiling.

There's absolute precision
about that,

which is really exciting,
I think.

It's not one of these
general alignments.

It's a very, very
precise alignment.

(narrator)
The blade of light seems to
point down

at the illuminated alcove,

which wasn't always empty.

The Roccabruna is built in such
a way that on the day

of the summer solstice,

the sun shines directly
through the window,

down to a spot where
a statue stood.

Now, the problem here is, we
don't know what the statue was.

(narrator)
What figure was so important
to Hadrian

that he wanted it illuminated
on that one special day?

There are various theories.

It could've been a statue of
the emperor Hadrian himself.

(narrator)
It would help if we knew
why the Roccabruna was built.

Based on
archaeological evidence,

the digital detectives
at IDIA Lab

reconstruct the original,
three-level structure

that, like the much larger
Pantheon, was designed

around an imaginary sphere.

But the purpose remains
mysterious.

And whatever statues once
stood inside

were stolen centuries ago.

Many are scattered in museums
around Rome.

But if we can find the right
statue for the alcove,

the purpose of the Roccabruna

and its dramatic solar spotlight

might be revealed.

Archaeologist
Marina De Franceschini

and archaeoastronomer
Giuseppe Veneziano

uncover a telling clue.

A marble candelabra in
the Roccabruna

bore Egyptian images,

including snakes
and a musical instrument

associated with
the Egyptian goddess Isis,

a goddess also worshipped
by many Romans,

including, perhaps, Hadrian.

The Isis cult centered around
a lot of healing,

and there's also an aspect
of reincarnation,

return from the dead...

(narrator)
And an important day of
celebration in the Isis cult

was the summer solstice.

These clues lead archaeologists

to comb through
the catalogue of treasures

looted from the villa.

They find no fewer than
four statues of Isis

in various museums.

The statues of Isis were
situated within the villa site.

In thinking about Roccabruna,

the summer solstice is also
a feast day for Isis.

So it seemed to be
a logical connection.

(narrator)
But would an Isis statue
fit into the space

of the empty alcove?

IDIA Lab calculations show
it would.

We've proven that there actually
is a substantial

solar alignment that's
significant on that date.

So, when we did
the reconstruction

working with the scholars,

the advised us to place the Isis
in that main central niche.

(narrator)
So, we have evidence that
a statue of Isis

stood here, but why?

Perhaps, Hadrian built this
temple as a kind of machine,

to focus the sun's rays

and honor the great goddess
who promised eternal life.

But Hadrian also controlled
the sun

in another part of his villa

that's been hidden for
almost 2,000 years.

A mysterious temple with
a surprising connection

to Egypt.

The temple was dedicated
to Hadrian's one great love...

and it wasn't his wife.

(narrator)
Hadrian's Villa,

17 miles east of Rome.

Here, almost 2,000 years ago,

the emperor Hadrian created
solar special effects

for his own private purposes,

including in one place that
was forgotten for centuries.

A mysterious temple
not unearthed by archaeologists

until 1998.

Up until recently,
they didn't know

it really even existed
because...

Earth had replaced
what little was left.

(narrator)
Based on detailed
archaeological evidence,

the temple rises again
in virtual reality.

But as the team at
Ball State University's IDIA Lab

fits the puzzle pieces
back together,

new mysteries arise.

Why would a Roman emperor
build an Egyptian temple

with an obelisk

and statues dedicated to
the Egyptian god of the dead,

Osiris?

According to myth,

Osiris drowned in
Egypt's Nile River

before being brought back
to life by his wife,

the goddess, Isis.

(Markley)
Osiris was resurrected.

Therefore, Osiris becomes
associated with immortality

or what happens after you die.

(narrator)
But there's something odd about
the statues of Osiris.

While they have the costume
of the Egyptian god,

they have the body and face
of a real man.

And not just any man.

It's Hadrian's lover,
Antinous.

Hadrian met Antinous when
the emperor was nearing 50

and Antinous was 12 or 13.

The two became inseparable,

but when Antinous was
about 19,

during an official
tour of Egypt,

he fell from Hadrian's barge
into the Nile and drowned.

(Markley)
Was it an accident?
Was it a murder?

Was it jealous political rivals?

Was it even a human sacrifice

to try to restore health
to the emperor, Hadrian?

That was one of the rumors.

So we really don't know exactly
how and why Antinous died.

What we do know is,
Hadrian was heartbroken.

(narrator)
Hadrian set up statues,
shrines, and even cities

dedicated to his lost love
all over the empire.

And that was just the beginning.

Hadrian announced that Antinous
was to be deified.

This really didn't accord
with Roman tradition,

but he was the emperor
and he wanted Antinous deified,

so deified he was.

(narrator)
And because Antinous died
in the Nile,

Hadrian reimagined his lover
as Osiris,

the god who died in the Nile
and was then reborn.

But the temple of Antinous
hides one final surprise.

Because when the
virtual reality investigators

restore the obelisk,
rebuild the shrine,

and set up one of the statues
of Antinous as Osiris,

they find something
totally unexpected.

Neil Zehr,
one of our staff members,

noticed that on a certain date

the shadow of the obelisk that
was in the temple of Antinous

crossed the statue of Antinous,
and he thought,

"Hmm, isn't that interesting?"

(narrator)
The date of the alignment
was the 20th of July,

an ancient symbol of rebirth,

because July 20th
was New Year's Day.

But not in Rome.

In Egypt.

The Egyptian New Year
began with

the flooding
of the Nile,

signaled by the reappearance
after months in the underworld

of the star of Isis.

(narrator)
Because of the way
the Earth turns,

different stars are seen
at different times of the year.

July 20th marked
the pre-dawn return

of a star sacred to Isis.

The brightest star in the sky.

Known to the Romans, and us,

as Sirius.

To our eyes, Sirius appears
in the night sky

to be a single star.

But in fact, Sirius is
actually a binary star,

or two stars that are
associated with one another.

(narrator)
8.6 light years from Earth,

Sirius is twice as massive
as our own sun

and 20 times as powerful.

Its companion, Sirius B,
is a white dwarf.

But to the Egyptians,

the binary star was
a single light

whose return on July 20th

meant that the Nile would once
more give life to the land.

And so, Hadrian honored
his lover with an obelisk.

Like the blade of
a giant sundial,

this caught the sun
and cast its shadow

on Antinous as Osiris

on the day the star of
Osiris's wife

brought new life from the Nile.

A complex symbol
of rebirth and resurrection.

At his villa,
Hadrian used his mastery

of architecture and astronomy

to create special effects
with the sun

and honor his lover's memory.

But could the emperor
maintain his solar power

after his own death?

As it turns out,

Hadrian may have had a plan

for his own immortality.

(narrator)
Ancient buildings in
and around Rome

that have intricate connections
with the sun.

Is this one of them?

The Castel Sant' Angelo,

about a mile northwest
of the Pantheon.

Today a museum,

but in the year 138,

the mausoleum of
the emperor Hadrian.

A tomb that may have contained

Hadrian's final
solar special effect.

The tomb of Hadrian probably had
a statue of him

in a chariot pulled
by four horses.

Like Apollo,
who would have a chariot

pulling the sun through the sky.

(narrator)
The statue alone would identify
Hadrian with the sun forever.

But did the emperor
go even further?

In life,
Hadrian built the Pantheon

as a giant sundial

and turned the sun into
an imperial spotlight.

He set up temples to make
the sun honor the goddess Isis

and his dead lover.

Preparing for his own death

and his elevation
to full godhood,

Hadrian also designed his tomb

as a final trap for the sun.

Recent calculations reveal
an astonishing alignment

at the summer solstice.

IDIA Lab confirms that looking
from the steps of the Pantheon,

Hadrian's sun god statue
would have been

dramatically silhouetted
by the rays of the setting sun.

Another link there
to Hadrian and the sun.

(Fillwalk)
The Pantheon is oriented so it
faces the mausoleum.

When it was constructed,
that whole field was empty,

so you could see
from the steps of the Pantheon.

You could see the mausoleum.

Today in Rome,
both those structures exist,

but you can't see them because

there are city buildings
in between the two.

(narrator)
Using the sciences of
astronomy and archaeology,

and the power of
virtual reality,

the mystery of the Pantheon
has finally been solved.

Its oculus is just
one of many ways

that Hadrian captured the sun.

Building on a tradition
that began

with Rome's first emperor,
Augustus,

and continued with Nero
and his octagonal room.

But if Hadrian's Pantheon

boasted Rome's greatest
solar special effect,

the obsession of Rome's emperors
with the sun

didn't end there.

80 years after Hadrian's death,

a new kind of sun worship
comes to Rome,

from the stars.

Sometime in the past,
it was said,

a meteorite fell in Syria.

It was obviously
a sign from the gods

or a god itself.

The rock, shaped like
a black cone,

was worshipped as the
representative of the sun god.

Incredibly, in the year 218,

after a coup d'etat,

the power of the Roman state

was handed over to the chief
priest of the sun cult,

a 14 year old named Elagabalus.

Elagabalus decided to import
that entire sun cult

directly to Rome.

He brought the stone to Rome

and introduced the sun god

as the primary deity
of the entire city of Rome.

(narrator)
Rome's new number one god

was Sol Invictus,

the unconquered sun.

But Romans weren't ready to have
all the gods of Olympus

take second place to
a stone from Syria,

even if it had fallen
from the sky.

Elagabalus was murdered

in another coup d'etat.

His sacred meteorite was
shipped back to Syria.

Then, almost 60 years later,

Roman religion faced
growing competition

from Christianity.

The emperor Aurelian
brought back Sol Invictus.

Perhaps to counter
the one god of the Christians.

And at that stage,
the sun god Sol

becomes the chief god
of the Roman Pantheon.

(narrator)
But the sun god's reign
was short.

In the fourth century,
Rome became Christian,

and so did the emperors.

The old monuments
fell into ruin

or were also converted
to Christianity

like the Pantheon,

which is now a church.

But although the sun god
is gone,

the sun still shines.

And this church still displays

the 2,000-year old

solar special effects
of ancient Rome.

And atop Hadrian's tomb,

his sun god statue
has been replaced

by the archangel Michael.

But the angel is still lit
at the summer solstice

by the eternal rays
of the setting sun.