All language subtitles for Mysteries.from.Above.S03E01.1080p.WEB.h264-BAWD_track3_[eng]

NARRATOR: Flying through space,

a high-tech view from above

uncovers a strange expanse
on the surface of Mars.

CYLITA GUY: This find is potentially
huge for the future of space travel.

- (beep)
NARRATOR: Cutting-edge technology

looking down from space

reveals a centuries-old legend
in Earth's oceans.

TORRI YATES-ORR: Something
weird is definitely going on here.

NARRATOR:
NASA probes spot a vast hexagon

swirling around Saturn's north pole.

DAN RISKIN: This is honestly one of
the weirdest things in the universe.

NARRATOR: And satellites capture
a perfect doughnut-shaped lake

carved into the landscape.

GUY WALTERS: This is really weird.
So what happened here?

- (boom)

NARRATOR:
Everywhere we look on our planet,

there's evidence of the past.

In nature.

In buildings.

In relics.

Each holds a mystery

that technology
now allows us to see from above.

- (dramatic music)

NARRATOR:
What new secrets are revealed?

- (optimistic music)

NARRATOR: In the 21st century,

the view from above
has reached ever greater heights...

..uncovering mysteries
not just on Earth

but across our solar system.

As we search for clues on Earth
to solve these cosmic enigmas,

technology reveals that outer space

holds answers
to some of our own abiding secrets

and may even hold the key
to the future of human space travel.

- (tense music)

NARRATOR: The Red Planet Mars

is Earth's
most tempting neighbouring planet.

DAN RISKIN:
Mars really does feel like

the next frontier
in space exploration.

TORRI YATES-ORR: Since the 1960s,

we've sent probes and orbiters
to explore the planet from above,

searching for clues
about its history

and what it can reveal
about planet Earth.

GEORGE KOUROUNIS: Today, there
are even rovers on the surface,

and space scientists
are looking forward to the day

humans can fly a mission to Mars.

PETER SOROYE: To chase that dream,
scientists investigate

the Martian surface with the images
and data captured from above

to find places
where humans could land.

TORRI YATES-ORR:
A landing site needs to be close

to major areas of interest,

including where
signs of alien life could be found

and any resources
that could support a human mission.

NARRATOR: And one team
of researchers examining

a possible Martian landing site
finds something astonishing.

- (tense music)

DAN RISKIN: It's amazing.
I mean, you think of Mars,

you expect this boring desert
of flat, orange nothing.

But this is stunning.

NARRATOR: Images
captured of the Martian surface

reveal an unexpected bright area.

GEORGE KOUROUNIS: This is wild

because you just don't expect
anything on Mars to look like this!

It's just completely
the wrong shape and colour.

DAN RISKIN: It's not
the jagged black of volcanic rock

and it's not the red waves
of iron-rich sand dunes.

So what's happening on Mars
to make these light tones?

PETER SOROYE:
And this is pretty big.

It's around six kilometres long
and four kilometres wide.

That's seven times bigger
than Central Park.

NARRATOR: Millions of kilometres
further away from the sun,

in the Kuiper Belt,

advanced space technology
looking down from above

may uncover a clue.

- (intriguing music)

TORRI YATES-ORR:
In the summer of 2015,

the New Horizons probe
reached Pluto,

over nine years
after it was launched from Earth.

CYLITA GUY:
Until this major milestone,

the best view we had of Pluto
was from the Hubble Space Telescope.

So when the first images of
the dwarf planet finally reached us,

the difference was staggering.

DAN RISKIN: New Horizons captured

a huge bright feature
on the side of the planet

that looks like a heart.

GEORGE KOUROUNIS:
The size of this is staggering,

about 16-hundred kilometres across.

That's over three times longer
than the Grand Canyon.

NARRATOR: But what is making this
huge light-coloured shape on Pluto?

PETER SOROYE: Pluto
is over three billion kilometres

from the sun on average,
making it pretty chilly...

an unbelievably frigid

minus 232 degrees Celsius.

CYLITA GUY:
It's so cold that nitrogen, methane

and carbon monoxide in its thin
atmosphere can actually freeze.

DAN RISKIN: And this deep-space ice

collects on unique terrain.

Most of the heart
is this massive basin

that's filled in with a thick layer
of these weird kinds of ice.

NARRATOR:
Could the bright area on Mars

be a vast ice field
like Pluto's heart

and will these secrets bring humans
closer to exploring Mars?

DAN RISKIN: Mars's atmosphere
is more than 95% carbon dioxide.

So would it be possible for that

to solidify into
an ice patch on the surface?

CYLITA GUY: Mars does sometimes
have ice and frost made of CO2,

but it doesn't always stick around.

ROMA AGRAWAL:
Mars isn't as cold as Pluto.

For carbon dioxide
to stay solid as ice,

it needs to be pretty cold...

around negative 125 degrees Celsius.

GEORGE KOUROUNIS:
At the poles or overnight...

no problem.
Temperatures can drop to minus 130

or even minus 150 Celsius
in winter at the poles.

But when the sun hits...

everything changes.

PETER SOROYE: On Earth, we know

frozen or solid carbon dioxide
as dry ice.

And if you think about
what happens to that

when it hits normal temperatures,

you can start to visualise
what happens on Mars

every time the sun
starts to warm up the surface.

DAN RISKIN:
It's something called sublimation.

It's when something goes
from a frozen solid to a gas

so fast that it just skips
the liquid stage altogether.

CYLITA GUY:
And this weird light area on Mars

is right by the equator.

While it can get down to below
minus 70 degrees Celsius at night,

this isn't quite cold enough
for CO2 ice.

DAN RISKIN: And at noon, It can get
up to a balmy 20 degrees Celsius

at the surface.

But even then,
because of the thin atmosphere,

if you go up just one-and-a-half
metres above the ground,

you're already
down to zero degrees Celsius.

- That's far too warm for
any CO2 ice to really stick around.

GEORGE KOUROUNIS:
So what else could be going on?

What other clues can we find?

NARRATOR:
A closer look at the NASA images

suggests something surprising.

- (intriguing music)

TORRI YATES-ORR: This bright area on
Mars is full of geographic features

that look shockingly familiar.

NARRATOR:
There may be a clue closer to home

here on Earth in Iceland.

GEORGE KOUROUNIS: Iceland is
known as the land of fire and ice -

and for good reason. It has some of
the world's most active volcanoes

and some of the largest glaciers.

NARRATOR: This is Vatnajokull,

one of the largest ice caps
in Europe.

DAN RISKIN: This massive
chunk of slow-flowing ice

covers over
75-hundred square kilometres.

CYLITA GUY: There is
more to this chilling beauty

than meets the eye.

Active volcanoes
are hiding under the ice.

TORRI YATES-ORR: But
it's the glaciers that hold the clue

to the strange bright region
on Mars...

particularly the dramatic
Svínafellsjokull glacial tongue.

DAN RISKIN:
If you look at the glacier tongue,

where it hits the sea,

you can see some cracks in the ice
that are starting to spread outward.

And if you look at the shapes,

they look an awful lot
like the ones on Mars.

CYLITA GUY: There are also bands of

earth and rock
in these really long wavy piles.

These are called moraines -

material
that's either been picked up

by the sides of the glacier
or pushed together by the front.

ROMA AGRAWAL: And they create shapes

nearly identical
to the strange area on Mars.

GEORGE KOUROUNIS: And this
wasn't the only icy clue in Europe.

NARRATOR: Around 26-hundred
kilometres to the southeast

is another stunning ice form,

high in the Austrian Alps.

- (tense music)

NARRATOR:
This is the Pasterze Glacier.

PETER SOROYE:
Climate change is chasing

this epic glacier into the past.

It's been receding since the 1850s.

100 years ago,
it was over 11 kilometres long.

Today, it's less than
eight kilometres long,

and it's dropped in mass
by over 50%.

- (dramatic music)

DAN RISKIN: But for now it still
holds clues to the Martian mystery.

NARRATOR:
Its stunning crevasse-like shapes

reveal signs of the flow
of water and ice over the terrain.

DAN RISKIN: Circular crevasses

with these concentric rings
of cracks

can happen
when there's water flowing under

or on top of
or even within the glacier.

These wear away at the ice,

and then the ice gets weak spots,

and when it gets unstable enough,
it collapses.

- And these cracks
that look like hash marks

are called
tic-tac-toe crevasses.

They occur when the glacier ice

flows on top of a higher area
in the landscape,

which stresses it
in different directions,

creating this unique crack pattern.

TORRI YATES-ORR: And
when you look at them side by side,

these look uncannily
like the fracture shapes

on the Martian surface.

GEORGE KOUROUNIS:
The weird shape on Mars

has the hallmark features
of a glacier.

NARRATOR:
Could a glacier be the secret

to this unexpected feature
on the Martian surface?

GEORGE KOUROUNIS: If we're able

to find a source of water,
even if it's frozen ice,

that would make
further explorations of Mars,

especially by humans,
so much easier.

It could change everything.

DAN RISKIN:
Water could be used for everything,

from drinking to feeding plants.

It could even
be converted into rocket fuel.

NARRATOR: But there's a problem.

ROMA AGRAWAL: The satellites and
probes that look at Mars from above

have found
signs of water ice glaciers.

But there's a key difference.

DAN RISKIN:
Any glaciers at the surface

are nowhere near the equator,

and that is because of sublimation.

CYLITA GUY:
Water is really unstable on Mars,

and that's because of
its thin atmosphere.

The atmospheric pressure
is more than 100 times less

than here on Earth.

PETER SOROYE: Because of the
low atmospheric pressure on Mars,

instead of liquid water
boiling at 100 degrees Celsius,

like it does on Earth,

it actually turns into gas
at around ten degrees Celsius.

Basically, if it's not frozen,
it's boiling or evaporating away.

TORRI YATES-ORR: So if
it can't be a surface water glacier,

what's going on?

NARRATOR: What clues can be found

by the advanced probes
searching Mars from above?

TORRI YATES-ORR: The Mars
Reconnaissance Orbiter, or MRO,

has been flying high above
the Red Planet for over 17 years.

Packed with high-tech equipment,
it offers a crucial clue.

ROMA AGRAWAL: When the researchers
looked at the data from the MRO,

they found that the light area

was actually a kind of salt.

- (dramatic music)

NARRATOR:
But how did this salt appear?

- And how can salt on Mars

make shapes just like those
we see in glaciers here on Earth?

NARRATOR: A mystery whose answer

may still hold the key
to human missions to Mars.

- (dramatic music)

- There's a clue on Earth
that provides

the final piece of the puzzle.

- (intriguing music)

NARRATOR: Hiding
only a few decades in the past,

in the bright red waters
of Bolivia's Laguna Colorada

is a staggering secret.

GEORGE KOUROUNIS:
The lakes of this region,

in the high plateau
known as the Altiplano,

are extremely salt and form

large and dramatic salt islands
in the brilliant waters.

ROMA AGRAWAL: But in the 1980s

scientists discovered
something incredible

hiding in these salty shells.

Ancient ice.

CYLITA GUY: The researchers
believed that this ice was formed

during the Little Ice Age,
which started in the Middle Ages.

DAN RISKIN: This thick layer of salt
insulated this ice against melting,

so it could stick around for decades
or even centuries, even though

in the bright sunlight
the summer temperatures

get to, like, 16 degrees Celsius.

PETER SOROYE: And
these aren't just little ice cubes.

These ice-cored salt islands were
as large as 1.5 kilometres across

and seven metres high.

TORRI YATES-ORR: It's unknown
if the ice persists to this day,

but the hidden ice implies

something staggering
about the shape on Mars.

NARRATOR: Could the salt
and the glacial-looking terrain

at this strange bright area on Mars
be a sign of ice hiding below?

DAN RISKIN: Experts believe
there is a way this could happen.

First, a long time ago,
a Martian volcano could have erupted

right next to a water ice glacier.

GEORGE KOUROUNIS: The hot ash
would have instantly melted

the top of the ice,
and - as it evaporated away -

it would have left a layer of salt
behind, hidden by the dark ash.

CYLITA GUY: Eventually, Martian
winds would have blown the ash away,

leaving behind
the bright salt layer,

which would hold
the shape of the glacier beneath.

GEORGE KOUROUNIS: Even though
this isn't 100% confirmation,

it's really important because,
if it is there on the surface,

that changes everything.

- (tense music)

ROMA AGRAWAL: Glaciers
have been found on Mars before,

but in the unfriendly and extreme
environments at the Martian poles,

where the icy temperatures
and long winter nights

would wreak havoc
on humans and electronics alike.

PETER SOROYE:
And at such cold temperatures,

simply turning that ice
into liquid water

could be a near-impossible task.

CYLITA GUY: But this glacier
is at the much more accessible

warm and sunny equator.

And digging through a crust of salt
is going to be far easier

than trying to break up polar ice in
negative 50-degree Celsius weather.

GEORGE KOUROUNIS: If there really is
ice hiding under this salt,

it'll be a total game changer.

- (tense music)

NARRATOR: This shocking discovery
on Mars is just the beginning.

CYLITA GUY: This find is potentially

huge for the future of space travel.

The possibility
of accessible frozen water

makes the logistics of a mission
to the Red Planet a little simpler.

Mind you, not simple,

but just a little bit easier.

GEORGE KOUROUNIS: What we're seeing
here in this view from above,

even though it's on another planet,

could change
the direction of human history.

NARRATOR: Advanced
satellite technology in space,

looking down from above,

captures planet Earth
like never before.

- (dramatic music)

DAN RISKIN: The US has all kinds
of cutting-edge equipment in space,

and a couple of satellites
have something called

the Visible Infrared Imaging
Radiometer Suite, or VIIRS.

CYLITA GUY: It's amazing.

Sensors collect
visible and infrared images,

which can be used to do everything
from predicting the weather

to tracking fires and even
sensing changes in the ocean colour.

ROMA AGRAWAL: And crucially,
it has something called

the Day Night Band Sensor,

which can see
in very low light conditions

to capture things at night that
we can't see with the naked eye.

NARRATOR:
And this new view from above

captures a long-hidden secret
in the nighttime darkness

of Earth's oceans.

In the summer of 2019,
off the coast of Java,

this technology
reveals an eerie shape

emerging
from the black ocean waters.

- (tense music)

TORRI YATES-ORR: Something weird
is definitely going on here.

PETER SOROYE:
From the satellite, it looks

so otherworldly and ethereal.

CYLITA GUY: This looks like
an abstract work of art.

I see this glowing cloud
floating in the black.

DAN RISKIN: It's paler than the
city lights on the island of Java,

but it's definitely brighter
than the nighttime ocean should be.

GEORGE KOUROUNIS: It's hard to tell
exactly what's going on here,

but it's huge.

CYLITA GUY:
This shape covers a massive area,

100,000 square kilometres.

That's like the size of Iceland.

- (eerie music)

NARRATOR: This strange vast shape

moves over time
and raises countless questions.

TORRI YATES-ORR: What is causing

this enormous
glow-in-the-dark spectre?

PETER SOROYE: Is this some kind
of weird natural phenomenon

or is it caused by humans?

CYLITA GUY:
How long has it been here?

DAN RISKIN: Is there
any other technology in space

that could offer a hint
as to what we're seeing here?

NARRATOR: Over
8,000 kilometres to the northeast,

off the coast of Siberia,

satellites looking down from space

capture a possible clue...

in the Sea of Okhotsk.

Familiar-looking shapes
swirling in the water.

- (tense music)

CYLITA GUY:
In 2023, NASA captured this,

as thinning ice breaks up

and starts to flow
with the spinning ocean currents.

DAN RISKIN: As sea ice melts,

swirls of white
spin off into the ocean.

Here it covers
hundreds of kilometres.

PETER SOROYE:
These happen here every year,

and sometimes last for months.

It's even appearing
earlier and earlier

as sea ice breaks up sooner,
thanks to climate change.

- This swirling ice,
seen from space,

looks a lot like the shape we see
in the images from around Java.

CYLITA GUY: Does that mean
that forming or melting sea ice

could be behind the mysterious
swirl in the Indian Ocean?

NARRATOR:
Further investigation from above

uncovers some shocking clues.

This isn't the only place this
strange phenomenon appears.

ROMA AGRAWAL: The VIIRS equipment
finds several more instances

of these strange
glowing patches of sea.

NARRATION:
These weird phenomena are spotted

off the coast of East Africa

and in the waters
of Southeast Asia.

DAN RISKIN: And there's something
all of those sites have in common.

They're all
in warm tropical waters.

PETER SOROYE:
That means there's no way

these could be caused
by melting or forming sea ice.

So what else could cause huge
areas of the ocean to get so bright?

NARRATOR: Perhaps
a record-breaking event in Spain

can reveal a clue.

In January of 2020,

the Mediterranean
is hit by a major storm.

- Winter storm Gloria batters Spain

with unparalleled heavy rain,

high winds and blizzards.

NARRATOR: And the quiet
seaside town of Tossa de Mar

faces something staggering.

DAN RISKIN: Storms can cause
something called a storm surge,

where the sea level
rises up higher than normal

and then floods coastal areas.

CYLITA GUY: And Gloria's storm surge
poured more than just water

into the streets of Tossa de Mar.

The town suddenly flooded
with a staggering amount of foam.

- (wind whistles)
PETER SOROYE: Sea foam occurs

all the time,
and all around the globe.

It's made when
the agitation of wind and waves

stirs up the organic material,
pollutants, surfactants

and general bits and bobs
that are found in seawater.

DAN RISKIN: To get sea foam
in these large quantities,

there has to be
a lot of dissolved organic material,

like a big algal bloom,
getting broken down.

And you have to pair that
with choppy ocean waters,

like a big cyclonic storm.

NARRATOR:
Could the churning ocean waves

make a giant island of sea foam
visible from space

or is there something else
hiding in the ocean depths?

TORRI YATES-ORR:
Maybe it's not a sign

of organic material breaking down.

Maybe there's
something alive down there.

- (tense music)

NARRATOR: There may be a clue

in an old maritime legend.

TORRI YATES-ORR: Over centuries,
there have been reports from sailors

of a very weird phenomenon...

something they called "milky seas".

GEORGE KOUROUNIS:
Researchers poring over

ships logs and other historical
records found over 200 reports

of vast stretches of ocean

emitting
a starling white or green glow.

- When those are mapped
alongside the 12 instances

captured by modern satellites,

you can see that
it continues a pattern.

CYLITA GUY: These rare glowing
ocean waters are most often found

in the Arabian Sea
and Indian Ocean.

TORRI YATES-ORR: So are
these ocean hazes seen on satellite

the milky seas of maritime legend

and are there any contemporary

on-the-ground sightings
that could back this up?

- (tense music)

NARRATOR:
In an unbelievable moment of luck,

the vessel Ganesha
happened to pass through

the tail of ocean haze
captured by satellite.

And what they record from
the ocean surface is astonishing.

- The crew described
a vast and steady glow

coming from beneath
the ocean surface.

GEORGE KOUROUNIS:
Even more amazing...

they catch it on camera.

And that gives another huge clue
to what's happening.

CYLITA GUY: The crew see the ocean
glow as a pale white or green

because their perception
of colour is affected

by the dark and moonless night.

The human eye contains two types
of receptor cells - rods and cones.

Cones help us to see colour,

while rods work in low light
to help us see in grayscale.

Cone cells need
lots and lots of light to work,

which is why
colour vision decreases at night

or in other dark conditions.

DAN RISKIN:
But the cameras on the ship

aren't affected
the same way human eyes are.

So they capture the truth.

A glowing, greenish-blue haze

that spreads out for miles.

NARRATOR: It's a critical revelation
and raises the question...

what on Earth can make the ocean
glow from below?

GEORGE KOUROUNIS: There are
some other glowing ocean phenomena

that can give us a clue.

PETER SOROYE:
There are parts of the world

where the impact
of the waves on the shore

can make a magical blue sparkle.

Even the motion of fish or dolphins
swimming in the water

can create the same kind of glow.

- These stunning phenomena
are caused by a type of plankton.

Tiny living things are producing
light with their bodies

through chemical reaction.

They give off light
when they're moved around.

DAN RISKIN: But these creatures
only emit little flashes of light,

so it looks like it sparkles.

That's not what we're seeing
off the island of Java.

So could it be
another form of hidden life

that's making the sea glow?

NARRATOR:
There may be a clue in Northern Iran

where the salty Lake Urmia

makes a statement
visible from space.

PETER SOROYE:
In these satellite images,

you can see that this lake
actually changes colour.

There is nothing subtle about it.

CYLITA GUY: Scientists believe
this stunning colour shift

is caused by
microscopic organisms...

either algae or bacteria.

In very bright and salty conditions,

the algae, Dunaliella salina,

turns from green to red as it
makes these protective chemicals.

DAN RISKIN:
The bacteria, Halobacteriaceae,

actually produce a red pigment
that converts light into energy.

So when they appear
in large enough numbers,

they make the water look red.

PETER SOROYE: Lake Urmia shows us
that there are microscopic creatures

that can change the colour of water
for extended periods.

So could invisible bacteria

be behind
the glowing milky seas as well?

CYLITA GUY:
The latest research suggests

that a bioluminescent bacteria
known as Vibrio harveyi could be

the secret ingredient
behind these milky seas.

DAN RISKIN: The bacteria can thrive
under certain rare conditions,

and when they grow to huge numbers,

they collectively begin to glow.

PETER SOROYE:
Glowing is an adaptation that

in other ocean creatures
can be anything from

a lure for food to a warning to
a means of burning off UV radiation.

NARRATOR: But what's
driving these glowing bacteria

is still a mystery.

CYLITA GUY:
Milky seas are rare enough

that spotting them
and getting to them quickly enough

to test the waters for bacteria
is tricky.

So we won't know for sure

if Vibrio harveyi is the culprit

until more research is done.

NARRATOR: And this maritime legend

may hold hints
of something even more staggering.

TORRI YATES-ORR:
Glowing bacteria may hold a clue

not simply
to Earth's milky seas mysteries

but to life on other planets.

DAN RISKIN:
A lot of people think that

since bioluminescence
works so well

and it's evolved
so many times independently,

it's one of the key things
we should be looking for

when we look
for life on other worlds.

GEORGE KOUROUNIS: With tools like
VIIRS pointed toward outer space,

could we uncover
a milky sea on another planet?

Only time will tell,
but it's a tantalising possibility.

- (dramatic music)

LAUNCH ANNOUNCER: Three, two...

NARRATOR:
In 1997, the Cassini Orbiter

launches into the skies...
- (boom)

..beginning a 3.4-billion-kilometre
journey through space.

- (electronic hiss)
GEORGE KOUROUNIS: Its mission?

An in-depth examination of Saturn...

from above.

DAN RISKIN: As Cassini
comes down over the north pole,

it sees something truly incredible.

CYLITA GUY: This is amazing.

There's what looks like
a perfect hexagon

right at the top of the planet.

DAN RISKIN: This is honestly one of
the weirdest things in the universe.

GEORGE KOUROUNIS: It seems too
geometrically perfect to be real.

And this thing
is unbelievably massive.

Each side is 13,800 kilometres long,

and it's almost
25,000 kilometres across.

- You could fit
almost four Earths in there.

GEORGE KOUROUNIS:
How is it possible to have

what looks to be
a near perfect hexagon

at the north pole of Saturn?

TORRI YATES-ORR:
I mean, what is going on here?

What is this thing made of?

- Why is it there?

GEORGE KOUROUNIS:
Saturn is over a billion kilometres

away from Earth. So how can we
investigate such a distant mystery?

DAN RISKIN: When it comes
to solving mysteries like this,

sometimes you have
to start a little closer to home.

NARRATOR: Could clues
to this strange phenomenon

be found on Earth?

CYLITA GUY:
It seems odd to think about,

but there are actually
naturally occurring hexagons

all over our planet.

PETER SOROYE:
From beehives to snowflakes,

ancient rock formations to the
pinpoint-lenses of dragonfly eyes.

- But why does nature love
this shape so much?

NARRATOR:
Perhaps a clue can be found

in the heights
of Bolivia's Altiplano,

where a vast plain of white
can be seen from space.

- This is the Salar de Uyuni.

It covers
over 10,000 square kilometres,

making it
the largest salt flat in the world.

It's about the same size
as the Big Island of Hawaii.

NARRATOR: And viewed from above,

stunning patterns in these ancient
salts form a familiar shape.

CYLITA GUY: There are hexagonal
formations all across the surface,

around one or two metres across.

TORRI YATES-ORR: But what drives
the salt into the hexagon shapes?

PETER SOROYE:
For years, scientists believed

that the salt
was forming hexagonal ridges

from cracking under
the pressure of contracting.

ROMA AGRAWAL: This is something
that can happen in cooling lava,

and we can see the results
in impressive rock formations

like the Devils Tower in Wyoming

and the Giant's Causeway in Ireland.

CYLITA GUY:
These kinds of shapes form because,

as the lava cools, it contracts.

These contractions
stress the cooling rock,

which cracks,
forming these very efficient shapes.

DAN RISKIN: And that just happens
to be at 120-degree angles,

and those are the angles
that make a hexagon.

- (dramatic music)

PETER SOROYE:
The latest research reveals

the secret behind
the salt flat hexagons

is actually
in the movement of water.

DAN RISKIN:
What's happening at the salt flats

is really happening
in the water underneath the crust

in a phenomenon called convection.

PETER SOROYE: Technically,
convection is just the transfer

of heat across a space
by the movement of a fluid.

CYLITA GUY: The warmer,
less dense parts will rise,

while the cooler, more dense
material will sink down.

NARRATOR: At the surface,

water evaporates
leaving behind ridges of salt

that mirror the patterns of movement
hidden under the surface.

ROMA AGRAWAL: This movement
tends to form polygonal shapes -

and in perfect conditions,

where there's nothing
to interrupt the flow,

convection
loves to make hexagonal patterns.

DAN RISKIN: So, could the same
forces that make hexagons on Earth

be what's happening on Saturn?

CYLITA GUY: But Saturn's skies
aren't made of water.

DAN RISKIN: There isn't even
land on Saturn. It's a gas giant.

CYLITA GUY:
Gas giants are huge planets

made mainly of gases
like helium and hydrogen,

which surround
a comparatively smaller solid core.

TORRI YATES-ORR:
So you've got to wonder

if the same kind
of motion in water on Earth

can happen in gas...

on a much larger scale.

NARRATOR: Perhaps
images from the Cassini Orbiter

can provide a clue.

To the naked eye, Saturn's hexagon

appears pale yellow and blue.

But the bright shades
of the false colour images

taken right above the pole

uncovers depth and details
inside this vast alien shape.

DAN RISKIN: Those different colours

indicate
how deep you are in the hexagon.

The redder colours are lower down,

the blue is higher up.

PETER SOROYE: So we can see
that this isn't just right

at the very top of the atmosphere.
This has some real depth to it.

DAN RISKIN: And crucially, looking
straight down from above like this,

Cassini also shows you
that the hexagon is rotating.

TORRI YATES-ORR: So
how can a perfect shape like this

hold together
in the swirling gaseous atmosphere?

NARRATOR: There may be a clue
hidden in Earth's skies.

DAN RISKIN: Just like in the water
underneath the salt flats,

convection
also happens in the atmosphere.

NARRATOR: Convection is behind

the creation
of clouds and thunderstorms.

- (thunder cracks)

- And it's the key driver
of one of the most powerful

phenomena on Earth...

Hurricanes.
- (wind howls)

NARRATOR:
Could an epic cyclonic storm

be responsible
for Saturn's hexagon?

CYLITA GUY: But there's a problem.

This hexagon
isn't like Earth storms.

NARRATOR:
In 1981, the Voyager II space probe

approaches Saturn,

and this historic view from above

reveals something shocking
when it sees Saturn's north pole.

GEORGE KOUROUNIS:
And what did they find? A hexagon.

CYLITA GUY:
And since that first finding,

when Saturn's tilted just right,

we've even been able
to spot it from Earth.

- This strange shape
has been sitting right here

at Saturn's north pole for decades.

PETER SOROYE:
But how could a cyclone

last for such a long time?

- (dramatic music)

NARRATOR: A clue lies
over 600 million kilometres away,

where a space landmark

on another gas giant stands out...

Jupiter's famous red spot.

DAN RISKIN:
The red spot on Jupiter is iconic.

TORRI YATES-ORR: There have been
records of a red spot on Jupiter

since the 1600s.

And while we can't be totally sure
it's the same one,

it sure looks similar.

- From more modern records,

we know that Jupiter's red spot

is at least 150 years old.

Now, if those 17th century
images are of the same spot,

it could be over 350 years old.

TORRI YATES-ORR:
So is there something about

a gas-planet atmosphere
that can make

these enormous storms
live for decades or even centuries?

PETER SOROYE: Unlike Earth
and other rocky planets,

gas-planet atmospheres can stretch
for thousands of kilometres

before you reach the core.

DAN RISKIN: Basically,
gas giants just don't experience

the same kinds of factors
we have here on Earth

that make our atmosphere
so changeable from day to day.

So if something gets going,

chances are its gonna keep going.

CYLITA GUY: It's an important clue.

But is Saturn's hexagon a cyclonic
storm like Jupiter's red spot

or is there something more going on?

NARRATOR:
A closer look at Saturn's hexagon

reveals something staggering.

GEORGE KOUROUNIS: How crazy is this?

The centre looks like a hurricane.

- (tense music)

DAN RISKIN: This thing's huge.

The eye of this thing
is 2,000 kilometres across.

That's 50 times bigger than
the eye of a hurricane on Earth.

NARRATOR:
But this stunning whirlwind

is only a small piece
of the giant hexagon.

What other hidden forces could be
behind this colossal mystery?

GEORGE KOUROUNIS: With a shape
like this right at the centre,

it sure seems like
there's some potent convection

happening in the atmosphere here.

But could that have any connection
to the whole hexagon?

- (ominous music)

NARRATOR: In 2020,
Harvard scientists investigate,

running a simulation on NASA
supercomputers to test their theory.

CYLITA GUY: One that focused on

the sheer size
of Saturn's atmosphere.

DAN RISKIN: Their model
imagined clouds and winds

going down
to 10% of the planet's radius...

So like 6,000 kilometres deep.

Then they started looking at the
kinds of wind patterns that happen

when you combine
the planet's rotation

and that
really, really deep convection.

- (optimistic music)

CYLITA: Let's remember convection -

hot goes up, cold goes down -

is behind the hexagons
in our salt flats on Earth

and the power behind hurricanes.

- Their 3D model showed
something really amazing.

The thermal convection spontaneously

makes exactly the right kinds
of patterns all over the planet,

including at the pole.

Deep under the surface there are
these vortices, these cyclones,

that kind of pinch the jet stream
into that hexagon shape.

Because those air movements
are deep, they're stable.

So the forms they make
stick around for decades.

GEORGE KOUROUNIS: But this is space

we're talking about.
We can't close the case just yet.

DAN RISKIN:
These are just computer models

based on what we can see from
Cassini and a whole lot of guessing.

If we wanna learn more, we gotta
send a probe right into the hexagon,

and that's probably
at least a few years away.

Until we get
to the ringed planet ourselves,

Earth is gonna be
the only laboratory we have

to learn about how it all works.

- (contemplative music)

NARRATOR:
Far above the Canadian landscape,

satellites looking down from space

spot something uncanny

among the lakes
of Northern Saskatchewan.

PETER SOROYE:
There are over 100,000

lakes and rivers in Saskatchewan,

mainly left behind
by Ice Age glaciers.

- When seen from the skies,
one of these lakes

really stands out.

SHEILA HOFFMAN: There's a body of
water that looks almost like an eye.

It's almost perfectly round and
has an island right in the centre.

CYLITA GUY: Which kind of makes

the whole thing
look like a giant Cheerio.

GUY WALTER:
Now, the lake isn't huge.

It's about
four to five kilometres across

and the island itself
is about two kilometres long,

but it doesn't look normal.

CYLITA GUY: If you think
about the depth of the lake

along with its circular shape

it almost looks like
a crater that's filled with water.

TORRI YATES-ORR: What could have
created such a bizarre formation

and why does it look so different
from the surrounding lakes?

PETER SOROYE:
What forces are capable

of creating
huge circles on the Earth's surface?

- (tense music)

NARRATOR:
A potential clue could be hidden

around 6,000 kilometres away,

in the English village of Hanbury.

From above,
among a patchwork of farm fields,

lies an unexpected
circular crater filled with trees

concealing the heart of a disaster.

GUY WALTERS:
About 80 years ago, in 1944,

the UK is in the home stretch
of the Second World War.

- (artillery fire)

GUY WALTERS:
That's the year that you have

the D-Day landings in Normandy
and the liberation of Paris.

TORRI YATES-ORR:
But in the rural countryside,

hundreds of kilometres
from the front lines,

peace is about to be shattered.

GUY WALTER: On November the 27th,

at 11 o'clock in the morning,
there's this sudden explosion

that shakes
the entire village of Hanbury.

- (explosion)

GUY WALTER:
You've got this double blast

shooting this mushroom cloud
into the sky,

and it flattens everything
in a 13-hundred-metre radius.

TORRI YATES-ORR: The blast leaves

a huge circular crater
on the landscape.

It's around 250 metres across
and about 30 metres deep.

NARRATOR: But what explosive power
is behind this destruction?

Could the answer
be concealed below the surface?

GUY WALTER: What you've got here
is a highly secret

British bomb storage site,

known as RAF Fauld.

And this place stored
absolutely huge amounts

of various explosive munitions.

I mean, this place
was packed to the rafters.

TORRI YATES-ORR:
That's a lot of power in one place,

and if anyone found out about it
that would be a major target.

So did spies discover it
and plan its destruction?

Was it sabotaged?

GUY WALTER:
This is a part of England

that has long been targeted
by Axis air raids,

and the Nazis very quickly claim

that it's one of their V-2 rockets
that has caused this devastation.

- (explosion)

SHEILA HOFFMAN:
But this time, it isn't the Germans.

The investigation revealed
something shocking and tragic.

In the pressure of wartime,

a fatal mistake was made.

GUY WALTER:
It's very likely that someone

mishandled a live bomb.

Now, the thick walls of the mine
prevent an even worse catastrophe,

but what happened was bad enough.

TORRI YATES-ORR: About four million
kilograms of explosives,

including a whopping 500 million
rounds of rifle ammunition, blew up.

- (explosion)

TORRI YATES-ORR: It was one of the
largest explosions ever in the UK.

SHEILA HOFFMAN:
When you see it from above today,

the crater
is filled with trees and plants

and looks quite peaceful and safe.

GUY WALTER:
But the hole in the earth remains,

along with a number of explosives
still buried in those tunnels below.

NARRATOR: Could the
strange-shaped lake in Saskatchewan

be the result
of a World War II era weapon?

GUY WALTER:
While Japan lobbed shells

at a British Columbia lighthouse
in 1942

and Axis forces
hit the St Lawrence River

during the Battle of the Atlantic,

Saskatchewan
was well out of reach.

TORRI YATES-ORR: So
if this weird doughnut-shaped lake

isn't a sign of
some kind of human-made explosion,

what else could be going on?

SHEILA HOFFMAN:
What other forces can make

this kind of unique shape
on the landscape?

Is a powerful natural force
at play here?

CYLITA GUY: There's another
out-of-this world possibility.

- (meteor cracks)

PETER SOROYE: There are a few known
impact craters around Canada,

so it makes sense to think
this could be among them.

NARRATOR:
But when researchers venture

into the wilds of Saskatchewan
to investigate,

they uncover something revealing.

TORRI YATES-ORR: When they examine
the rock of the centre island,

they realise
something strange is going on.

NARRATOR: This isn't like any impact
crater they've ever seen on Earth.

CYLITA GUY: On Earth, you expect

two main kinds of impact craters.

Smaller impacts make simple craters,

which are basically just
these bowl-shaped holes.

Bigger impacts make
something called complex craters.

PETER SOROYE: When
these bigger meteors hit the ground,

it's so big and powerful,
has so much energy,

that solid earth
starts to act like a fluid

and rebounds or splashes up
in the middle of the impact hole,

like when a stone
is thrown into the water.

When that rebound of solid earth
drops back down,

you're left with a central peak.

GEORGE KOUROUNIS: If you look
at the shape of this lake doughnut,

it looks just like
a complex crater filled with water.

That's what the researchers
expected to find.

- (dramatic music)

NARRATOR: But what
they uncover is out of this world.

CYLITA GUY: Basically, the rock here
is the wrong kind of rock.

Whatever this central island is,

it wasn't made by the rebound
you see of a complex crater.

DAN RISKIN: But it can't be
a simple crater either

because the floor and the walls
are too full of debris.

CYLITA GUY:
The researchers realised

they'd seen
something like this before

but not on Earth.

NARRATOR:
The final clue to solve this mystery

can be found
by looking down from above

at our planet's nearest neighbour...

the moon.

PETER SOROYE:
Earth's moon is pockmarked

by countless thousands of craters

from the giant 25-hundred-kilometre
South Pole-Aitken basin

to the microscopic dents found in
moon rocks from the Apollo missions.

- Because of the lack of
atmosphere and plate tectonics,

the moon's craters aren't subject to

the same changes
we see here on Earth.

For example, they don't get hidden
over time by things like water.

As a result,
these craters can tell us

a lot about the history of the
meteoroid strikes that form them.

NARRATOR:
And one type of moon crater

could solve
the mystery in Saskatchewan.

DAN RISKIN: When you look at sort
of medium-size craters on the moon

from like 15 to 42 kilometres
in diameter,

you see something pretty special.

PETER SOROYE: These aren't
bowl-shaped, like simple craters,

but they don't have the central
peak of complex craters either.

DAN RISKIN: Instead, they're
kind of like this in-between stage

where they have some of
the traits of each type of crater.

These are called
transitional craters.

They have flat floors,

one or more terraces or rock slides,

like you'd see in a complex crater,

but with no central peak.

NARRATOR:
But can this happen on Earth?

CYLITA GUY: Transitional craters
form so easily on the moon

because of its lack of atmosphere
and low gravity.

So it's easier for larger objects
to hit more gently.

DAN RISKIN: But with
Earth's atmosphere and gravity,

we don't expect quite
so much of that middle ground.

Anything that would make
a medium hit on the moon

would accelerate
way more in Earth's gravity,

so it would end up being
a big punch, not a medium one.

- (meteor hisses)

CYLITA: Science basically thought
that finding that middle ground

here on Earth
was essentially impossible.

But this discovery
changes everything.

DAN RISKIN:
To find something

that we can confirm
is a transitional impact crater

and to see that
it's in such good shape,

this is groundbreaking.

PETER SOROYE:
But then you've got to ask...

how did the central island form

if not through
the initial space rock impact?

- (dramatic music)

DAN RISKIN: The crater
is about 200 million years old.

So it happened
when the Earth looked very different

from the way it looks today.

CYLITA GUY:
So it's hard to say for sure

what factors created the island.

DAN RISKIN: But the thinking
is that, over millions of years,

wind and rain would have worn down

the edges of the crater
until it was almost flat,

and that central dip
would have filled with sediment.

CYLITA GUY: Then, experts think that

the movement of glaciers over
the land during the last ice age

could have carved up the landscape,

including in this ancient crater.

DAN RISKIN:
Thanks to the melting glaciers,

water would have filled
these new scars in the landscape,

which merged with the crater
to form the lake as we see it today.

NARRATOR: This astonishing
discovery isn't just unprecedented.

CYLITA GUY: It's the chance to study

a phenomena we observe on the moon
right here on Earth.

This is what makes this discovery
even more exciting.

NARRATOR: Another Canadian
impact crater in Labrador

is already hosting
cutting-edge lunar research.

PETER SOROYE: The meteorite
that made the Mistastin Lake crater

left behind rocks
that are almost identical

to ones found all over the moon.

CYLITA GUY: So today NASA
uses the site to train astronauts

for their new moon mission -
Artemis.

DAN RISKIN: And this lake may hold

just as many lunar-style secrets.

CYLITA GUY: It's amazing to me

how much we can learn
about our solar system and beyond

from studying
features right here on Earth.

DAN RISKIN: I think this is cool
because we use the moon

to solve this mystery here on Earth.

But as we do
the research on the ground,

we uncover these secrets that are
gonna help us understand the moon.

- (wind whistles)

- (dramatic music)

NARRATOR: From signs of ice on Mars

and stunning shapes on Saturn

to hidden impact craters and
mysterious milky seas on Earth...

some of the grandest mysteries
are discovered from space.

And with the latest technology
looking down from above,

Earth's secrets can reveal
the truth about space

and resolve longstanding riddles
back home.

- (uplifting music)

- I love the fact that
we're learning more and more

about our own backyard
here in the vastness of space.

- And you just know that the next
find is right around the corner.

Subtitles by Sky Access Services