Narrator: We live in a violent Universe.
Planetary winds rage at six times the speed of sound.
Lightning storms stretch for thousands of miles.
Dust storms engulf entire worlds.
We can have planetary storms
the like of which we never see here on the planet Earth.
Narrator: The largest storms
can be on the scale of entire galaxies.
Sometimes those massive stars can literally explode.
Narrator: The universe is a chaotic place.
Earth has storms.
Other worlds have megastorms,
storms almost too vast to imagine.
Yet from the violence emerges a ray of hope.
We kind of owe our existence to these sorts of events,
these sort of galactic storms.
Narrator: Could megastorms be necessary for life itself?
♪ How the Universe Works 2x02 ♪ Megastorms Original Air Date on July 18, 2012
== sync, corrected by elderman ==
On some planets, storms are impossible.
Superheated Mercury is too small and too close to our Sun
to have a significant atmosphere.
And no atmosphere means no storms.
But move out away from the Sun,
and we find worlds with turbulent, chaotic atmospheres.
They can spawn some of the most awe-inspiring megastorms
in our solar system.
This is Venus,
a planet completely shrouded with clouds.
Winds rip around the upper atmosphere
at over 300 miles per hour.
About 35 miles above the surface,
the winds are whipping around in a ferocious pattern
that basically carries the cloud features
around the entire planet every four days.
Narrator: Venus is closer to the Sun than Earth,
and it's heat from the Sun that drives the wind.
Dr. Thaller: The circulation pattern of Venus' clouds
is actually quite simple.
There's a warm side of Venus and a cold side.
And as air warms up and rises on the day side of Venus,
it spreads around to the night side.
So, there's this continuous current
that's actually quite a lot simpler
than the atmospheric circulation on Earth.
Narrator: Venus' winds circulate faster
than the fastest hurricane on Earth.
But they look very similar.
The Venus Express probe captured these remarkable images
of the planet's south pole.
Kaku: One of the great mysteries of Venus
which actually had jaws dropping
in the halls of many astronomy departments
is the fact that we have hurricanes
at the poles of Venus,
especially in the southern hemisphere, that have two eyes.
Not one eye, but two eyes.
Now, we've never seen this before
on such a planetary scale.
Narrator: Venus' double-eyed vortex
is 1,800 miles wide.
Two hurricanes whirl around each other.
Dr. Grinspoon: If you could descend into the vortex of Venus,
something I would love to do,
at least with a remote machine...
...I think you would see
some kind of a fantastic wall of cloud
and this sort of twisting form
spinning around you at ferocious speeds.
It would be quite a sight.
Narrator: It's a mystery
how deep this raging, spinning vortex goes,
but maybe this megastorm eye
descends to the planet's surface.
Down here, permanent twilight bathes a volcanic landscape,
and the atmosphere's colossal weight
creates immense pressure.
The atmospheric pressure on Venus
is about 100 times that of the Earth.
Think of taking a car,
squeezing it down to about a square inch,
and putting it on every square inch of your skin.
You'd be flattened within a fraction of a second
because of all that pressure.
Narrator: Venus' dense atmosphere
creates one of the strangest megastorms imaginable --
four miles per hour winds
with the force of a hurricane.
The winds on the surface of Venus are actually very slow
because Venus has a very slow rotation rate.
It takes Venus about eight months
to turn once around with respect to the sun.
Narrator: The crushing atmospheric pressure
rams gas molecules together so tightly
that they feel more like a liquid.
A gentle 4-mile-an-hour breeze packs a brutal punch.
It's like a hurricane in slow motion.
Kaku: Winds on Venus
are totally unlike anything we see on the planet Earth.
You would almost feel, like, a molasses effect.
It'd be quite difficult
to simply walk and run right through the wind.
Narrator: Venus' surface is so hostile
that life is impossible here.
[ Thunder crashes ]
But the upper atmosphere's faster winds
hold an extraordinary possibility.
Dr. Grinspoon: I harbor this --
I don't know if I would call it a hypothesis
or a scientific fantasy.
But I do think it's plausible
that there could be some kind of life living
in the clouds of Venus.
There are certainly energy sources.
There's sunlight.
And there are certainly nutrients.
There's carbon, there's hydrogen,
there's oxygen --
all the stuff we think of that you need to make life
exists in the clouds of Venus.
Narrator: Earth's upper atmosphere is full of life --
microscopic bacteria drifting on the wind.
Could Venus be the same?
Perhaps one day we'll send a probe to find out.
Leave Venus behind, and the next planet is Earth.
Here, too, the weather gets extreme.
We are bombarded by tornadoes...
hurricanes...
and these -- dust storms.
On Earth, they're localized.
But on the next planet out...
they engulf an entire world.
Narrator: Over 100 years ago,
astronomers thought they had found life on Mars.
A dark wave spread from the pole towards the equator.
They thought it was springtime vegetation
spreading across the planet.
They were right about the season.
Mars tilts at roughly 23 degrees,
like the Earth,
so you would have summer, fall, winter, spring,
like the seasons.
Narrator: Seasons bring weather.
The shadow astronomers saw
was actually dark rock uncovered by a violent dust storm.
It's all because of the way the planet tilts.
The Earth takes one year to orbit the Sun.
In January,
the northern hemisphere leans away from the Sun,
and we get our winter.
In June, it leans inwards, our summer.
Mars has gigantic planetary dust storms
the like of which we've never seen here on the planet Earth.
Narrator: Mars has around the same tilt as Earth,
and springtime means storms.
The martian surface vanishes
under a cloud of raging dust particles.
On Earth, we get dust storms, too.
They can be devastating, swallowing entire cities.
July 5, 2011, Arizona.
An unstoppable 5,000-foot-high wall of dust
smashes into Phoenix.
Day turns to night.
Thousands of tons of dust settle over the city.
But the disaster stays in one place.
Mars' dust storms can engulf the entire planet.
On Mars, when dust gets kicked up once, it lands,
it can get kicked up again and again.
The dust is reusable.
On the Earth,
when the dust gets kicked up and then finally settles out,
it's probably gonna settle out into the ocean,
where it's gone for good.
There's nowhere on Mars
where there isn't ready dust and sand to add to that storm.
So, these storm systems can kick up
and last weeks or even months.
Narrator: Mars' incredibly dry atmosphere
contributes to the storms' size and power.
Showman: In the case of the Earth,
dust that gets up into the atmosphere
is rapidly washed out by the rain
and gets into the ocean.
In the case of Mars,
there's no comparable rain to wash the dust out.
So, once the dust gets into the atmosphere,
it just sits there
until the particles by themselves
are able to slowly settle out.
Narrator: A lack of rain
allows Mars' dust storms to cover the planet.
But dust storms on Mars
can be equally spectacular on a much smaller scale.
NASA rovers captured these extraordinary images --
dust devils sucking up fine, dry, iron-oxide dust.
The biggest dust devils can reach six miles into the sky.
They pump fine particles high into Mars' atmosphere,
creating a haze of dust
that may help control the planet's dry climate...
and lead to a planet-wide megastorm.
Even on Mars, dust storms this big are rare.
Astronomers have detected just 10
in the last 100 years.
What the ancient astronomers mistook for life
was a megastorm.
But even a planet-covering dust storm
is dwarfed by the weather
on the next planet out from our Sun.
This is the giant of our solar system --
Jupiter.
Narrator: Jupiter is gigantic.
It's 2½ times more massive
than all the other planets in the solar system added together.
It's also home to gigantic megastorms.
Jupiter's high-speed rotation
drives vast bands of counter-rotating clouds.
Colossal storms build along the boundaries.
And this is the biggest of them all,
the oldest storm in the solar system.
15,000 miles across and over 300 years old,
the great red spot.
Around the edges,
turbulent winds rage at over 300 miles per hour.
The great red spot is a giant vortex,
meaning that, in the case of the red spot,
it has a high-pressure center
with winds that swirl around the outer edge.
So, in that sense,
the great red spot is a little bit like a hurricane.
Narrator: A hurricane with a difference.
On Earth,
hurricanes feed off heat from the ocean.
When they hit land, they start to die.
So, on average, they last only about a week.
Jupiter does not have land.
Jupiter is a completely gaseous planet,
and the friction there is very weak.
And so a vortex, like the great red spot,
can last indefinitely.
There's nothing to slow it down.
Narrator: To keep going,
all the red spot needs is a power source.
On Earth, ultimately, that's heat from the Sun.
But Jupiter's five times farther from the Sun than us.
Heat from the Sun is not enough to drive the red spot.
Instead, Jupiter has an internal power source --
its own immense gravity.
In 1995, NASA launched a probe
straight toward the giant planet's heart.
It plunged into Jupiter's upper atmosphere
at over 106,000 miles per hour.
As it fell,
the planet's crushing gravity ratcheted up the pressure...
10, 15, 20 times what we feel on Earth.
Winds gusted to over 400 miles per hour.
The probe gave out just 100 miles in,
crushed by pressure
and fried by the incredible heat the pressure generated.
Had the probe made it deeper,
it would have reached a vast, silvery ocean.
Intense pressures here turn hydrogen gas
into a churning, metallic liquid,
superheated to over 40,000 degrees Fahrenheit.
Jupiter's interior pumps out about twice as much energy
as the surface gets from the Sun.
This is Jupiter's power source,
the heat that drives its massive megastorms.
Dr. Thaller: All of the convection, all of the heat
comes from the hot, dense interior of the planet itself.
So, the bands of clouds that you see
that are even counter-rotating, going in different directions,
those are all driven
by the internal heat of Jupiter itself.
Narrator: Jupiter's internal heat
drives its violent megastorms.
But the giant planet may hold clues to an even deeper mystery.
Could life exist on other worlds?
NASA's Cassini probe studied Jupiter
as it flew past en route to saturn.
It made an extraordinary discovery --
strange white clouds just north of the great red spot.
Clouds just like the clouds on Earth --
droplets of liquid water.
Could Jupiter have the ingredients for life?
The question of life on the giant planets
is an interesting one.
You have many of the ingredients for life.
You have sunlight coming in.
There's liquid water,
at least in the form of cloud droplets.
On the other hand, if life can easily exist in clouds,
you might expect that bacteria and algae
would populate the clouds on Earth
and the clouds would be green.
We don't see that on the Earth.
We do see microbes at many altitudes
throughout the Earth's atmosphere,
but they seem to largely be blown off of the surface.
Narrator: It's likely that life on Earth
began on a solid surface.
But could life evolve without one?
There's no surface on Jupiter,
and so that makes it difficult
for organisms to have a constant source of water.
So, if you imagine yourself
being a little bacterium inside a cloud droplet,
you're gonna be in deep trouble
when that cloud droplet evaporates.
Narrator: Whether life exists in Jupiter's clouds or not,
gas giants like Jupiter and its neighbor Saturn
have all the right ingredients --
water, heat, and one other vital element,
a spark...
[ Thunder crashes ]
...lightning on an unimaginable scale.
Narrator: These haunting images are from NASA's Cassini probe.
Its mission --
to explore one of the solar system's
most awe-inspiring planets...
Saturn.
The probe reveals Saturn's rings...
moons...
and the planet itself in near-perfect detail.
Chaotic bands of cloud race around Saturn
at more than 1,000 miles per hour.
Finding storms here was no surprise.
It's a planet of storms.
But this was astonishing.
A bolt of lightning --
a gigantic thunderstorm on an alien world.
[ Thunder rumbling ]
Lightning creates
some of the most spectacular weather on Earth.
[ Thunder crashes ]
Electrical tension builds between the top and bottom
of a vast 55,000-feet-high storm cloud,
a maelstrom of water vapor, rain, and ice.
Tiny ice crystals drive up past hailstones falling down.
As they rub past each other, it builds up a charge.
When the strain gets too great, you get an electric spark.
[ Thunder rumbling ]
[ Thunder crashes ]
On Earth, the average lightning storm stretches 15 miles.
On Saturn, they can reach around the whole planet.
There are examples of lightning storms on Jupiter and Saturn
where the anvil cloud --
in other words, the big cloud at the top of the storm --
starts small and grows to be 20,000 kilometers long.
That's the size of the Earth.
On Saturn, we registered one lightning storm
that was 10,000 times greater
than any lightning storm found on the planet Earth.
[ Thunder rumbling ]
Narrator: Lightning is hotter than the surface of the Sun.
The atmosphere literally explodes...
[ Thunder crashes ]
...the sound we call "thunder."
On Earth, it's the sound of new life.
[ Thunder rumbling ]
Lightning seems scary and destructive,
but actually it's very productive for life on Earth.
And the reason why is
because of its influence on atmospheric chemistry.
Narrator: Every bolt literally burns the air.
Dr. Grinspoon: When you have a lightning discharge,
you get this very high-temperature,
very energetic plasma,
and that breaks up the nitrogen molecules in the atmosphere,
frees up those nitrogen atoms
to enter into other kinds of molecules.
And those nitrates formed by lightning
allow nitrogen to go into the soil
as, basically, fertilizer,
enter into plants, enter into the life cycle.
So, it's the lightning that frees up nitrogen atoms
in the service of life on Earth.
Narrator: Earth experiences
8 million lightning bolts every day...
[ Thunder rumbling ]
...helping life evolve and colonize the planet.
But for Saturn, lightning alone may not be enough.
There's nowhere for alien life to live.
[ Thunder rumbles ]
One place in our solar system may solve that problem --
Saturn's moon Titan.
It has an atmosphere.
It has lakes of liquid methane...
....and its own bizarre brand of megastorm.
[ Liquid splashes ]
Narrator: Saturn is almost 900 million miles
from the Sun.
This far out, orbiting the Sun takes time.
Saturn's year is nearly 30 Earth years long.
Right now, it's spring, and things are heating up.
Now we're moving into the summer cycle of Saturn,
so the atmosphere is slightly heating up.
Even as distant as Saturn is from the Sun,
we've got a little more energy
and we're seeing the most spectacular storms
we've ever observed on Saturn.
Narrator: After years of frozen silence,
Saturn is coming alive.
Scientists have waited nearly 15 years
for the Sun to light up its north pole,
to reveal extraordinary details
about one of the strangest megastorms
in the solar system....
Saturn's unique hexagon storm.
Kaku: A hexagonal pattern, how can that be?
In mother nature, we have jagged objects.
We don't have geometric figures arranged precisely,
especially on a gigantic planetary scale.
However, there's some theories.
If I take a bucket of water or a bathtub
and simply vibrate it,
I get waves, waves that travel.
But there's another kind of wave.
You have traveling waves,
but then you have stationary waves.
Inside a bucket of water, you can get resonances.
Water pulsates like this.
And you can also get them to pulsate in a circle like this
to create regular patterns.
These are called stationary waves,
and we think
that this mysterious hexagonal pattern on Saturn
is a hexagonal standing wave.
Narrator: The megastorm at Saturn's north pole
is a wind that travels at hurricane speed,
cornering sharply six times
as it races 'round the planet.
The central clearing is so big,
you could fit four Earths inside.
What lies beneath its surface is a mystery.
As Saturn warms from spring to summer,
another world comes alive, too.
One of Saturn's moons, Titan, is warming up.
And with the warmth come the storms.
Krauss: One of the most interesting moons in our solar system
is Titan.
It's straight out of science fiction.
It's an object with yellow skies and methane clouds
that is truly remarkable.
Narrator: NASA's Cassini probe
reveals Titan in unprecedented detail...
a thick, dense atmosphere,
vast mountain ranges,
lakes of liquid methane.
And this --
an arrow-shaped band of white methane clouds
moving over its surface.
When the clouds drifted over a dusty, open plain,
seen here as a dark patch,
the dark patch of ground beneath the clouds grew larger.
Scientists believe
liquid methane drenched the surface.
A spring rainstorm, Titan style.
Rain on Titan, if it exists,
would be very different from rain on the planet Earth.
First of all, the gravitational field is very weak,
so you would actually see raindrops falling
very slowly at you.
Also, the size of these droplets could be much larger.
But don't get caught in a rainstorm on Titan.
Those droplets are awfully cold.
Narrator: Titan's methane monsoon
sweeps across the moon.
Weak gravity creates ultra-cold, hazelnut-sized raindrops.
An alien world with truly alien weather.
These slow drops have carved valleys and lakes
much like ours on Earth,
a slow-motion megastorm.
But fly even farther out through the solar system,
and you find storms that are altogether faster.
This is super-chilled Neptune.
The temperature never gets above 300 degrees below zero.
Neptune is one of these giant planets.
It's much larger than the Earth and has a very thick atmosphere.
It's about 2 billion miles out from the Sun.
So, you really might expect,
since it's that far from the Sun,
it would be very cold and not have very much weather.
But in fact, Neptune is very dynamic.
It's got tremendous weather patterns.
Narrator: Despite its incredible distance from Earth,
astronomers can get close
to Neptune's turbulent atmosphere...
with a little help from this.
The Keck Observatory,
14,000 feet up on the summit of Mauna Kea in Hawaii.
It sits above Earth's clouds and pollution.
The telescopes are so powerful
they could see a candle on the Moon.
Neptune at first appears featureless.
But a closer look reveals white, high-altitude clouds
in the upper atmosphere.
It's a perfect opportunity to track wind speed.
Measuring the time and distance
the clouds take between two points
allows scientists to clock their speed.
The Keck telescope swings towards Neptune.
A series of shots track the white clouds
as they move around the planet.
So, here we can take several photographs
that show the positions of clouds apparently changing.
You can measure the position at one moment to be there
and at another time a few hours later
to be in a different place.
Now, most of that change in position
is due to the rotation of the planet as a whole.
However, if you know the rotation rate
and subtract that out,
that gives you the motion of the clouds
relative to the planet.
That tells you the wind speed.
Narrator: The results are shocking.
Filippenko: We're seeing wind speeds on Neptune
of many hundreds of miles per hour
up to 1,200 or even 1,260 miles per hour
for the very fastest clouds.
That's really phenomenal.
Narrator: Neptune has the fastest winds in the solar system.
So, what's driving this?
You need energy to make weather. Where's that energy coming from?
And it turns out it's coming from Neptune itself.
It does receive sunlight,
but Neptune actually radiates away more energy --
a lot more energy than it gets from the Sun,
which means the interior is very hot.
Probably it means there's radioactive material in there,
there's leftover heat
from when Neptune formed 4.5 billion years ago
that's very slowly leaking out.
And it's that that's heating up the air
and driving all of this circulation
and all of this crazy weather that Neptune has.
Narrator: Neptune's storms hit hard.
But the search for truly extreme weather
takes us out of the solar system altogether
into uncharted territory.
Out here, there are storms
that make even Neptune's winds look like a breeze.
Katrina was just a sneeze
compared to the winds we have on Osiris.
Narrator: The search for megastorms
leads to alien worlds
whose violence defies imagination.
Narrator: Space is full of stars and planets
where violence and chaos reign.
Astronomers scour the skies for new worlds.
And the king of the planet hunters
is Professor Geoff Marcy.
He scans the night sky
seeking new worlds around distant stars.
Marcy's team has instruments so sensitive
they can even predict the weather
on these distant planets.
This is Osiris,
150 light-years from Earth,
a planet from hell with matching weather.
Earth is 93 million miles from the Sun.
It orbits the Sun in one year.
But Osiris is just 4 million miles from its star.
Its year races by in just 3½ days.
When Osiris passes between us and its star,
starlight briefly shines through its atmosphere,
giving us a glimpse of conditions on the alien world.
And they waited until the planet was in front of the star.
At that moment, some of the starlight
passed through the atmosphere of the planet.
They were able to do essentially a chemical assay,
a chemical assessment
of the composition of this atmosphere.
Narrator: Osiris gets blasted by the intense heat of its star.
Temperatures top 2,000 degrees.
Marcy: Now, what that means is
that the environment on that planet is,
well, hideous for life as we know it.
But even more, the intense heat causes the gases to expand,
and they have no place to go but the backside of the planet.
Narrator: Osiris is tidally locked.
The same side of the planet always faces the star.
The other looks out into space.
The temperature difference is immense.
Superheated atmosphere roars
from the bright side of the planet to the dark
at nearly six times the speed of sound.
Marcy: In fact, the winds
will be something like 2,000 or 3,000 miles per hour,
enormous speeds of these winds --
10 times, 20 times faster wind speeds
than the strongest hurricanes.
Katrina was just a sneeze
compared to the winds we have on Osiris.
Narrator: Osiris is a brutal world,
too hot and too violent
for any kind of life we could imagine.
But there are even larger megastorms,
storms on the scale of whole galaxies.
And these fast storms may be the reason any of us are here.
The Hubble Space Telescope captured this stunning image
of the Galaxy NGC 3079.
At its center, a super wind --
a storm on a truly cosmic scale.
It was triggered by an explosion from a forming star.
This raging galactic storm is about 3,000 light-years wide.
It has already raged for around one million years.
Filaments of 20 million-degree gas
tower above the spiral galaxy.
This cosmic megastorm
wreaks havoc within its host galaxy.
We see bubbles and jets
and formations of gas falling into the galaxy,
colliding with galactic dust.
Narrator: The gas from the galactic megastorm
smashes into gas and dust at the heart of the galaxy
and compresses it into a swirling mass of matter.
Gravity takes over.
The compressed clouds of gas and dust
get tighter and tighter.
The center gets hotter and hotter.
Finally, it ignites.
Powerful winds from the new star blast into space.
The whole cycle begins over again,
and a new galactic megastorm is born.
Around the fledgling stars,
dust and rock come together,
the birth of new worlds
with rocky surfaces where life could begin.
Kaku: And perhaps the formation of life itself
may be determined
by how these gases swirl and create super-galactic storms.
And if you have galactic winds churning away,
then that would help to distribute
the elements necessary for life throughout the galaxy.
So, galactic storms may, in some sense,
be one clue to the formation of life itself.
Narrator: Galactic megastorms rage for millions of years.
Billions of years ago,
they may have created new homes for life
in our Milky Way galaxy.
On every scale, storms are not just a force of destruction.
They are linked to creation itself.
The search for life on other worlds
is also the search for storms.
When you disrupt the status quo,
you open all kinds of possibilities
for things to reassemble in different ways.
So, chaos or disruption is actually an important factor
in the development of complex systems like life.
A planet that might have changes of seasons,
vulcanism, intense storms,
some environmental factors
that you might think could be damaging to life,
in the long run makes life stronger.
Narrator: Earth has storms.
Other worlds have megastorms.
Whether it's lightning on Saturn,
the turbulent atmosphere of Jupiter,
or blistering temperatures on Osiris,
vast, violent, and deadly megastorms
could also be the catalyst for life.
== sync, corrected by elderman ==