The Universe (2007–…): Season 1, Episode 3 - The End of the Earth - full transcript

Earth, the only life-sustaining
planet in our Solar System.

Yet throughout its history our world
has been a planetary punching bag.

Anything that
crosses the orbit of Earth

could one day slam into the Earth.

At this very moment, violent celestial
heavyweights roam the Universe

and threaten to deal the
Earth a knockout blow.

The power would be like setting off
the whole world's armament at one time,

and would be like standing next
to Hiroshima all over the world.

Everything in us would get ripped apart

and all of your body
would fly off to infinity.

But some scientists
and former astronauts



are not willing to go
down without a fight.

They're racing to track
down these cosmic killers

before they trigger Armageddon.

Earth, shimmers like a sapphire
jewel in our Solar System.

We go about our days,

unaware that, in the
far reaches of space,

trouble could be headed our way.

Our Solar System is a lot
like an amusement park.

Earth and most of the other objects
carve predictable paths around the Sun.

Normally everything is calm and smooth,

but at times things
get chaotic and violent.

Earth can be slammed by space rocks,
zapped by deadly space weather,

jolted, jostled and threatened

by the objects' energy
and forces of the cosmic.



The Earth is on a cosmic thrill ride,

one that often involves extreme danger.

When you're moving fast in
on a pre-determined path,

you hope nothing crosses, because
there's nothing you can do.

Nicaraguan border is right down along...

Former astronaut Rusty
Schweickart knows first hand

how dangerous celestial objects can be.

In 1969 he piloted the lunar
module during the Apollo 9 mission.

Now Schweickart is ready for
more than a cruise to the cosmos.

He's sounding alarms about the
dangers of one particular asteroid,

named Apophis,

which got too close for comfort in 2004.

He had immediately got
everybody's attention, because

the probability of
impact was quite high.

In fact it was higher
than any impact probability

that we had ever seen
up until that time.

And Schweickart has a terrifying
real life example of just how damaging

an impact from an asteroid, even
smaller than Apophis, could be.

June 30th 1908, 7:15 AM.

An object, half the
size of a football field,

plunged down from space at
around 34,000 miles per hour.

And produced a stream
of fiery gas behind it.

Within minutes, the fireball
entered our atmosphere,

and violently exploded about
Siberia's Tunguska forest.

It became the largest explosion
on Earth in modern human history.

The blast sparked heatwaves,
which torched 8 million trees

in an area over half
the size of Rhode Island.

Fortunately no one died as a
direct result of the explosion,

because it was in a
thinly populated area.

If that asteroid hit
just a few hours later,

it would not have hit Siberia,
it would have hit over Europe.

And if that had exploded midair over
any of the major cities of Europe,

a million people would died like that.

For the last hundred years,

the Tunguska explosion has
been shrouded in controversy.

Today many scientists agree
an asteroid caused the blast.

Incredibly, it never
even impacted the ground.

Rather, it exploded five miles
above Siberia's frozen ground.

A small stony asteroid can't survive
the plunge through Earth's atmosphere.

When it smacks into
the lower atmosphere,

doing about 50,000 miles an hour,

it's like an egg smashing
on the concrete.

The blast over Siberia released energy
equivalent to 15 megatons of TNT,

a thousand times greater than Hiroshima.

If this were to happen over a
large city, it would annihilate it.

Scientists call these trespassers,
Near Earth Objects, or NEOs.

They're asteroids and comets,

which are leftovers from
the formation of the planets.

Comets move in the Oort
Cloud in the Kuiper Belt,

which is beyond the planet Neptune.

Asteroids travel in a band
between Jupiter and Mars.

But their orbital trip
isn't always routine.

Most of the asteroids orbit in a
neat belt between Mars and Jupiter,

And we don't worry much about those.

But when one gets away,
and all that mass and energy

is headed towards Earth, that's
when the astronomers start to worry.

Often times these cosmic remnants
get bumped out of her orbit,

and head on a collision
course with Earth.

Our planet's thick atmosphere
vaporizes the vast majority of it.

But a larger object can
knock through our atmosphere

and actually impact the ground.

If you want to turn to the cosmos

and look at the forces
that would have us dead,

asteroids striking are
real and they're bad.

It's happened before,
it will happen again.

65 million years ago,

an asteroid the size of a small city

plummeted down from the sky.

It exploded in the Yucatan peninsula

near the present day
Mexican village of Chicxulub,

with the force of one hundred
million megatons of TNT.

Here's the Earth... cast...

billions of tons of Earth's
crust into the atmosphere,

cloaking Earth, blocking out sunlight,

knocking out the base of the food chain

and sending a wave of extinction
across the tree of life.

It is believed the ferocious impact

contributed to the mass
extinction of the dinosaur.

We can think of asteroids
as being bad things,

but if it were not for an
asteroid we wouldn't be here today.

Our mammal ancestors were
running underfoot,

trying to avoid being
hors d'oeuvres for T-rex.

T-rex gets taken out.

Well this opened up an ecological niche,

that allowed our mammal
ancestors to evolve

to something more ambitious
than a rodent

and out comes the primates and
among the primates we have people.

But ironically the very
kind of cosmic boulder

that paved the way for humans to exist,

may one day wipe us off the planet.

In 1998 Congress urged NASA to
detect all the Near Earth Objects

over a half mile in diameter or more.

And what they found was unsettling.

Over 850 NEOs in our vicinity.

These asteroids are our closest

and most dangerous neighbors
in the Solar System.

Donald Yeomans heads the NEO program
at NASA's Jet Propulsion Laboratory.

He and his cosmic bounty hunters

search for potential killers
lurking in our Solar System,

and put them on their most wanted list.

Finding these Near Earth Objects is
somewhat akin to tracking hurricanes.

As you track it, day after day,
you get a better idea of its orbit,

you can predict where it's going,
you have a better idea how large it is

and, if it should hit the Earth,
with what sort of velocity.

By using telescopic technologies

NASA's Spaceguard Survey has detected
over 90% of all NEOs deemed harmful.

These frightening objects could
strike the Earth with the energy

greater than all the nuclear
weapons on our planet today.

Such an impact could
trigger mass extinction.

We wouldn't expect one to hit but

every several hundred
thousand or millions of years,

but if one did it, it could wipe out
a fair fraction of the population.

So they are very low probability
events but high consequence events.

If they hit the Earth they
would have global effects.

They not only would you wipe out a
continent with really heavy shockwaves,

but the ejected would
be thrown up in the air

and come down all around the planet,

the atmosphere itself would get
to a thousand degrees or so...

And all the vegetation all over
the world where that happened

would flash into flames.

Cataclysms could also
occur with smaller objects,

so Congress now asks NASA to locate
all NEOs 500 feet in diameter,

as wide as the roman Colosseum.

An object that big could decimate a
metropolitan area or even a small state.

And what worries scientists most is
not the asteroids they've discovered,

but the ones they have not yet found.

At any given time
there's about 2000 objects

for which we can't yet
rule out an Earth impact.

Former astronaut Schweickart has taken
the threat of NEOs one step further.

He's appeared before Congress

to request a special
government agency be responsible

for protecting the
public from space rocks.

Today we have the technology to stop

Near Earth Objects
from impacting the Earth

for the rest of history.

I mean, we can literally now

begin to reshape the local Solar System,

so that our survival is enhanced.

The question is: will we or will
we go the way of the dinosaurs?

But Schweickart isn't waiting for
NASA or Congress to solve the problem.

He has his own plans to save the
planet from the next asteroid impact.

It's hard to believe the Earth has
survived over 4.5 billion years,

because since its infancy the
planet has taken a beating.

Like a boxer, our world
is under constant assault

from asteroids that
enter our orbit each year,

but in the future Earth
could be knocked out.

Former Apollo 9 astronaut,
Rusty Schweickart refuses

to be bullied by asteroids,

and now he's ready to defend
Earth against these harmful rocks.

We've discovered that there
are these Near Earth Objects

flying by us all the time,

and we've got more and more
capability to modify our environment to

enhance our survival.

Schweickart is particularly concerned
about an asteroid named 2004MN4,

better known as Apophis.

This pockmarked rock,
approximately 750 feet in diameter,

swept near Earth in 2004.

Now it's scheduled to pass
dangerously close to our planet again,

on Friday, the 13th in April 2029.

So in 2029...

Apophis will come closer to us

than our own communication
satellites orbiting the Earth.

It will be so close that people who are
in the right place will be able to see

Apophis go by the Earth
with your naked eye.

You won't even have to have binoculars,

that's how close that
asteroid is gonna come.

Apophis has an over 99% chance
of missing the Earth in 2029,

but if Apophis passes the Earth at
a distance of exactly 18,893 miles,

it may pass through a
gravitational keyhole,

a narrow region in
space, a half mile wide.

If this happens, the Earth's
gravity could upset Apophis,

and change its trajectory.

It could cause it to return,
and hit Earth seven years later,

on April 13th, 2036.

The gravitational effect of the
Earth, would cause it to bend,

cause the Apophis' orbit to
enlarge to precisely the size, which

seven years later it will
come around and hit the Earth.

At the present time, Apophis
has 1 in 45.000 chance

of delivering a deadly blow in 2036.

But even these odds have
scientists placing bets.

It's one thing to know that
there is maybe 1 chance on 45.000,

that it's gonna hit the Earth,
but what you'd like to know is

if there is one chance in a hundred,
is there one chance in ten,

if there is a probability one
that it's gonna hit the Earth.

Schweickart believes
we must regard Apophis

as we would any natural disaster.

He's even mapped out
where Apophis might strike.

You have the date of the impact,
the time of the impact,

the orbital inclination,
and you can make a map.

And what that map shows, is what
I have called a "path of risk",

that goes all the
way across the planet.

And I look at this and I see a high
probability of impact and I say...

Wow! You know, where might it hit?

According to Schweickart,

Apophis could impact any point
along this "path of risk".

It begins in Western Siberia,

cuts across and down the
Pacific Ocean, near California,

then it traverses Central America
and finishes in Western Africa.

Schweickart proposes a chilling
scenario of where Apophis might strike.

The asteroid could land in the Pacific
Ocean off the coast of California,

with a force of over one
million megatons of TNT.

Such an impact would create

a 5 mile wide, 9,000 foot
deep crater in the water,

which would unleash tsunamis.

Relentless 50 foot waves
would pound the coast line,

resulting in unimaginable human loss.

An asteroid that's
a thousand feet in diameter,

having it hitting the
ocean is not a good deal.

Hundreds of billions of dollars
of damage, from something like that.

Scientists are presently
working on technologies

to pre-empt such a cosmic strike.

One idea involves
blowing up an asteroid.

But some feel this could
compound the problem,

sending several chunks of the asteroid
in our direction instead of just one.

Consequently, Schweickart's new mission

is to change the orbit of
asteroids that could impact Earth.

What you wanna do is basically

change the asteroid's
orbit very, very slightly.

Change its velocity by a ten
thousanth of a mile per hour,

so that it will miss the
Earth instead of hitting it.

Rusty's colleagues have
drafted a conceptual designs

of a spacecraft that could deflect
asteroids. Particularly Apophis.

One would tow harmful
asteroids away from Earth.

But instead of lassoing the
rock like a bull in a Rodeo,

the tractor will hover in front of
it, and use gravity as a tow line.

If you park in front of an asteroid
for a long enough period of time,

and you stay close enough
to it, but not touching it,

you're going to increase its
velocity, or, if you park behind it,

while it's moving along, you're
going to slow it down very slightly.

We can change the orbit of an asteroid,

if we know about it far
enough ahead of time.

Although a space probe has
landed on an asteroid in the past,

the most challenging idea is
launching a manned mission.

Once landing on the rock, astronauts
could mount a radio transponder,

to track its whereabouts.

You could just use a robotic mission
to go to an asteroid, and land,

grab a sample and bring it
back. That's not that difficult.

What you gain by a manned
mission is they can

react to interesting areas on the
asteroid's surface. They could go here,

there, there. And they wouldn't
have to rely on remote navigation.

Nicaraguan border...

Schweickart insists we should remain on
high alert regarding asteroid Apophis.

And his cause hasn't gone unheard.

Now the United Nations
plans to draft a treaty,

which will include who
will be responsible

for deflecting killer asteroids.

That would be a real crime
if we are so irresponsible,

knowing that this is gonna happen,
that we continue to do nothing about it.

But asteroids and comets are
not the only deep space threats.

Earth has had its ups and...
Earth has had its downs.

You never know what's gonna be around
the next corner, and a lot of it is bad.

In far-off galaxies,
galactic invaders are at work,

itching to end life on
the planet, as we know it.

Three times daily, a strange
flash pulsates across our sky.

It's hundreds of times more powerful
than the world's total nuclear armament.

But it's not man-made.

And if one happens
close enough to Earth,

it could end life on our planet.

Most earthlings are unaware of
the potential hazards in space.

But the list is long and growing.

Imagine this.

Within our own galaxy, the Milky
Way, a massive star explodes,

sending a lethal burst of
energy rocketing toward our planet.

This is a gamma-ray burst,

the biggest explosion to rock
the Universe since the Big Bang.

In the cities and countryside below

there's no warning of
what's about to happen.

And then, it strikes.

It would be equivalent to standing
one mile away from Hiroshima,

any place on the Earth.

The potent radiation
cooks the upper atmosphere.

Our ozone layer roasts.

Across the hemisphere, human beings
burn to death from radiation

a hundred times the fatal dose.

The disappearing ozone layer causes
increased temperatures around the world,

triggering cyclones,
tsunamis and hurricanes.

Most life on the surfaces of
land and water incinerates.

This may seem like science fiction,

but it could happen, if a
gamma-ray burst hit Earth

from 100 light years away.

Gamma-ray bursts are the brightest
explosions in the Universe.

Because they are so far away

and they are still so
brilliant they must involve

an enormous amount of power.

As much energy as the Sun will emit

in its entire ten
billion year lifetime.

As a young student,

Stan Woosley always liked
experiments that go "boom".

Now, the work of this astrophysicist

is more than child's play.

He's one of the galactic detectives

trying to uncover the mysteries

behind gamma-ray bursts.

We know there're many
planets and many stars

throughout the cosmos,
so there may have been

countless civilizations that
were destroyed by gamma-ray burst.

These peculiar beams of radiation

were first spotted in the 1960s.

At first most astronomers
believed these gamma-ray bursts

must exist in our own
galaxy, the Milky Way,

because they're so bright.

There were reasons for that, one
was if they were outside the galaxy,

the energy was almost unbelievable.

But at the time,

even the most powerful telescopes

couldn't determine their
location and distance

because the bursts

lasted for a few seconds

then disappeared.

But then astronomers wondered,

what about their afterglow?

Cosmic explosions typically
leave behind some luminous residue

that sometimes lasts for days or weeks.

In the late 1990s

satellites used upgraded optics

and x-ray detectors

to finally capture a
gamma-ray burst afterglow.

It became clear that gamma-ray
bursts actually were... cosmological,

coming from very far
outside of our galaxy,

from millions and billions
of light years away.

And that meant their energy
had to truly be astronomical.

You get some idea of
how incredibly bright

a gamma-ray burst is...

We could represent the
brightness of our Sun

by this relatively dim LED

and we can represent the
brightness of the gamma-ray burst

by the very very intense searchlight

that's behind me,

ain't that incredibly bright?

Unfortunately with this comparison,

the searchlight is not
nearly bright enough

to represent fully the gamma-ray burst

and in fact we would need a hundred
billion such searchlights

to have an adequate comparison.

The gamma-ray burst is equivalent

to the brightness of a
million trillion suns.

This massive bursts
could decimate Earth.

But what causes them?

We are quite convinced that
the common gamma-ray burst

comes from the death of a massive star,

at least ten times the mass of the Sun.

And such stars are
quite rare by the way.

Woosley masterminded
a ground-breaking model

of how gamma-ray bursts
may be created.

When an extremely massive star dies

it collapses into a black hole.

Black holes are created when a
collection of matter collapses

to such a high density that

light itself cannot escape.

But Woosley proposes
that some of the star

resists getting sucked into
the center of the black hole.

As result, a high speed spinning
disk of matter forms around it.

Within seconds, jets of plasma
shoot out from its rotational poles.

These beams of energy unleash
dangerous gamma rays into space.

So if you can imagine
just trying to squeeze

a fruit or some kind of sphere of
some object into a very small space

things are gonna squirt
out and in this case

the squeezing is done very rapidly

and you're talking about
a huge amount of mass.

At the same time the gamma
ray bursts are ejected

the collapsing star explodes

or goes supernova to the extreme.

One of the reasons gamma-ray
bursts are so incredibly bright

is that they take an
enormous amount of power,

and then they focus that power into
a very small portion of the sky.

For every 300 gamma-ray
bursts that go off

only one is pointed in our direction,

and so we only see 1 of those 300.

Even if a gamma-ray
burst were to occur

not 100 but 1000 light years away,

the Earth could still face
apocalyptic destruction.

If a gamma-ray burst happens within
100 light years off the Earth,

then it would be approximately
500 times brighter than the Sun

and emmitting gamma rays.

The energy delivered to
the Earth's upper atmosphere

would be like a 100,000
megatons of nuclear explosions.

The ozone would be depleted,

we'd have acid rain but
we'd also have flash burns,

incineration of vegetation, perhaps
something resembling nuclear winter.

So there could be a global
extinction of many species.

Now the far side of the Earth
would be a special place to be,

because gamma rays don't
go through the Earth

and if you were on the other side,
you wouldn't get flash-burned.

But the effects of depleting the ozone

and changing the
composition of the atmosphere

would eventually come
to the other side,

and there the effects are unknown.

Statistically this ghastly scenario

has 1% chance of happening once
in the Earth's entire lifetime.

But even these odds aren't reassuring

if you're living on the
planet at that very moment.

If you're caught in the beam...

that's a bad day for you.

If one of this happens in your galaxy
and that beam is coming your way,

go hide in a cave.

Because this is very
high energy radiation.

It's the kind of energy that
would decompose your molecules,

and you just don't wanna be...
be around when that's happening.

There currently are
no defense measures

to shield us from gamma-ray bursts
if they happen close to Earth.

They travel at the speed of
light: 186,000 miles per second.

By the time we detect them, they
would have already struck our planet.

Gamma-ray bursts could pose a hazard

to the Earth or to anything living that

came within their bore site.

But as we've seen,
they're very infrequent

and there are other
things in the heavens

and on the Earth that
are much more dangerous.

Cataclysms routinely erupt in
some corner of the Universe.

And one day something
will snuff out Earth.

Most of the time our ride
around the Sun is

gentle and uneventful
like this Ferris wheel.

And as long as nothing
gets in our way,

we could go on like this
for millions of years.

But sooner or later we know that
this smooth ride will come to an end.

We just don't know when.

Sadly our planet's ultimate demise

will probably come from the
very thing that provides us life.

Earth maintains a cozy lifestyle
being third rock from the Sun.

For over 4 billion years
the Sun has been an ally,

warming and feeding our planet.

But in time our solar
heater will become our enemy.

The Sun and the Earth have a
unique relationship to each other.

The Earth has a particular temperature,
a particular size, it has life on it

and oceans. And those
things depend on the Sun.

The Sun is at the root of the
existence of life on the Earth

and the Sun will be at the
root of its demise as well.

Earth's relationship with the
Sun will become dysfunctional

when our solar mother
really turns up the heat.

The Sun gets hotter because it's
burning hydrogen into helium.

Four hydrogen atoms
become one helium atom.

That means there
are fewer particles

dancing around inside the Sun.

And that process basically
means that the Sun has to get

hotter and brighter to hold itself up.

As the Sun's core gets hotter its outer
parts will swell in size and turn red.

If you have a bonfire, you have
all this wood there, you build it up,

and at some point enough logs
get burnt and that thing collapses

and you get this huge burst of
sparks and it gets much brighter.

In a sense it's like
that because the Sun is

right now burning
hydrogen into helium

and the helium is the ash
of that, if you like...

And then as the Sun collapses
enough, the ash relights

and the helium burns into carbon.

And that's when things get really hot.

At this point Sun will
expand into a red giant,

and incinerate most
complex life on Earth.

When the Sun becomes a red giant
it will grow to 30 times its size

so the surface of the Sun will actually
be out beyond the orbit of Mercury.

The luminosity of the Sun will
go up by like 1000 times.

That's gonna make
the Earth so hot that

the outer crust, the rocks, the
solid part of the Earth... will melt.

The whole planet would
be a glowing ball of lava.

The Sun will fry the
inner planets and...

even though the Sun will
become red and cooler,

the Earth will be much hotter.

Just leave the Earth a burnt cinder,
like a charcoal bricket.

So that would be
bad for life on Earth.

And the Earth's hellish
fate isn't over.

As a red giant, the Sun
will fluctuate in size

before collapsing
into a white dwarf.

The Sun that was huge,
suddenly becomes

a Sun that's very small
and extremely dense,

only about the size of the Earth,

sitting down there at the
center of our Solar System,

very much fainter than it used to be.

And everything cools off and
then that object is no longer

generating energy either,
so it begins to cool as well.

The final fate of the Solar System
will be to cool off and freeze.

Humans will probably have
relocated to another planet

or become extinct before the
Sun turns Earth into a snowball.

However the Sun may dry
up our world much sooner.

If the Sun doesn't get us at
the time of the red giant phase,

it may well get us earlier by

just becoming bright enough to
cause the oceans to evaporate.

Water is an essential
component for all our life

and so if Earth actually loses all its
water then that's another reason why

life might disappear from the Earth,
and it would again be the Sun's fault.

There may be ways for Earth
to win a stay of execution.

As the Sun is swelling,
it also begins to lose mass,

much more rapidly than
it's losing it now.

And of course if it's
getting less massive

it has less of a hold on the Earth.

The Earth will move further
out, into a larger orbit.

And so it's kind of a race between
the growing Sun and the growing heat

from the Sun and the
Earth, actually moving,

you know, a little bit away from
that fire that's getting too hot.

If our planet somehow
manages to avoid getting

fried or frozen by the Sun,

its future remains increasingly bleak.

This place is full of adventure.

Rides that put your stomach
up in your throat,

things that collide, scary stuff...

It's a lot like riding around
the Sun on planet Earth.

But when Earth gets smacked or
when things start to come apart,

the ride could really be over.

I don't know what that means
for the Universe to end,

because I like time, I live in it.

So it's hard to imagine time ending.

Today scientists contemplate
our inevitable fate.

In the distant future, the
Earth and the entire Universe,

may face the ultimate cosmic monster.

No one suspects that Earth's most
lethal enemy lurks amongst the stars.

But in the future, and
without prior warning

a cosmic grim reaper will
unleash the ultimate Armageddon.

The dark villain will
stretch apart the Universe.

Galaxies themselves will split apart.

Stars and planets will tear to shreds.

The ultimate apocalyptic event
is being called "The Big Rip".

And when it begins it won't stop

until every atom and nuclei in
the Universe aren't minced meat.

"The Big Rip", it really
is the end of the Universe.

It's not like we're the last ones at
the party, wondering what's going on

and we can go do something else.

It's really like you've
turned off all the lights.

And the Universe just ends.

Innovative physicists Robert
Caldwell and Marc Kamionkowski

proposed the notion of "The Big Rip".

A grim hypothesis about the
final fate of the Universe.

We used to think that the Universe,
which is currently expanding,

can reach a point of maximum expansion.

"The Big Rip" is the
idea that the expansion

will not only continue and accelerate,

but rip everything apart as it does so.

Caldwell and Kamionkowski calculated
that the Universe is expanding

at an alarming and increasing pace.

And that something is sucking
everything outward like a vacuum.

Acting like a galactic vice squad,

these young scientists
hunt for the cosmic killer.

They believe a mysterious
phenomenon called dark energy

may be the culprit.

Figuring out what dark energy is,

is probably the number one
goal of cosmologists today.

Dark energy is "dark"
so you can't see it.

We can feel what it
is, we feel that through

its effects on the gravitational
behavior of the Universe.

There could be some dark energy
in this room, under the chair...

It's only when you
look at its properties

on really big cosmological
length scales,

billions of light-years
across, that you start to see

the accumulative effects
of the dark energy.

It causes things to be pushed
farther away from each other

and contributes to the
expansion of the Universe

and a quickening pace.

Edwin Hubble, whom the Hubble
telescope is named after,

first discovered the Universe
is expanding back in the 1920s.

But it wasn't until the 1998

when a crack team of scientists
measured that this expansion

is moving like a runaway train.

A nice analogy is to
imagine that the Universe

are three-dimensional
spaces like the surface of a

rubber balloon
that I'm blowing up.

Ok, I'm gonna blow the
balloon as a demonstration

of the effects of the
expansion of the Universe.

Here's the balloon gets bigger
that's the depiction of the

expansion of the galaxies.

First galaxy, another one...

- These are galaxies...
- Okay.

- One over there.
- Okay. That's our home.

As the Universe expands every other
galaxy gets farther away from us.

In ordinary expansion each
galaxy stays the same size.

But if you have super
accelerated expansion,

then the galaxies
themselves can each expand.

Which is a sort of what happen here.

If I could blow it up fast enough
to depict "The Big Rip" then

the balloon would explode.

That's like space-time not
being able to... take it.

And coming to an end.

So, insted we'll just
pop a hole in the balloon.

That's "The Big Rip".

According to Caldwell
and Kamionkowski,

the Universe has no hope
of surviving "The Big Rip".

They've even come up with a
countdown to this apocalyptic event.

"The Big Rip", kind
of rolls up its sleeves

and progressively takes apart
the Universe layer by layer.

Working from the outside in,

going from the larger
scales to the smaller scales.

A billion years to pull
apart clusters of galaxies,

then hundreds of millions of years
to pull apart galaxies themselves.

And then, down to the
size of the Solar System,

we're talking hundreds
of thousands of years.

And then to tear apart the
Earth itself will take...

less than an hour.

It's kind of interesting to think
about what that would look like.

If I'm in my protective
capsule watching things happen,

I would see this wall of darkness
that starts coming towards us.

I would no longer, at that
point, be able to see any stars.

The Earth layer by
layer would be peeled off

and ejected away.

Everything in us, the
molecules that hold us together,

would get ripped apart and...

every atom that makes
up your body would get...

would get... would fly off to infinity.

In a very short period of time.

Fortunately mankind doesn't need
to lose sleep over "The Big Rip".

Caldwell and Kamionkowski
estimate that it will climax

fifty billion years from now,

when the Universe is over
three times its current age.

What's really fun for us
is to try to figure out

whether this is actually
what's going to happen,

to paint a science fiction scenario

of what might happen and to
think what might happen to us.

Deep space threats are real?

Sun could harm us tomorrow?

Others in the far future.

But one thing is certain.

Something will terminate Earth
and probably the entire Universe.

Once and for all.

It's only a matter of time.

It's useful to sometimes think about,

how fragile our life is here on Earth.

That maybe we're not
gonna be here for eternity.

Maybe there's a hope.

But... they way it looks...

The Universe just ends.

And that's it.