Original subtitles

Narrator: Supermassive black holes --

Gargantuan monsters that lurk at the center of galaxies.

Right now you are traveling at half a million miles an hour

Around a giant black hole

Four million times the mass of the sun.

Narrator: But there's a mystery about these colossal beasts.

We have no idea where they came from.

How did they get so big so quickly?

We know they weren't "born" or created that way.

It doesn't make sense.

Narrator: Today, investigators are seeing

Tantalizing glimpses of an entirely new type of black hole.

This thing essentially jumped at me.

Narrator: Could this new breed of black hole

Be the seeds that built the supermassive monsters?

It is almost a kind of cosmic miracle.

Narrator: And might they even hold a clue

To how the milky way itself formed?

Oluseyi: It sounds crazy and like science fiction,

But it's science reality.

Narrator: The race is on to find the missing link

That will reveal how supermassive black holes

And the galaxies around them were created.

I would say this is the golden age of black hole physics.

Narrator: This is the final chapter in our cosmic creation story.

♪

-- Captions by vitac -- www.Vitac.Com

Captions paid for by discovery communications

At the very heart of every large galaxy lurks a monster --

A supermassive black hole.

These are the undisputed heavyweight champions

Of the cosmos.

There's a trillion galaxies in the observable universe,

And each one has a supermassive black hole in its center.

Narrator: Supermassive black holes can weigh

As much as six billion suns, and all that matter

Is packed into a tiny point in space.

They'll suck in anything that strays too close.

Planets, stars, not even light can escape.

A black hole is a bottomless pit of gravity

That actually draws in material all around it.

Plait: If you get too close,

There is no force in the universe

That you can apply to yourself to get back out.

Narrator: But as well as being the ultimate agents of destruction,

Supermassive black holes bring order to the universe.

Their colossal gravity corrals countless stars

Into orbit around them, forming the hearts of galaxies.

Plait: We think that the galaxy itself

Depends on that supermassive black hole for its structure.

If these things didn't exist,

Galaxies would look completely different.

Narrator: But a big mystery surrounds supermassive black holes.

We have no idea where they came from.

How does the universe compress the mass of six billion stars

Into a single point in space?

The answer won't just tell us

How supermassive black holes form.

It may reveal how the galaxies

That fill the universe came to exist, too.

If we can understand how supermassive black holes grow,

Then that's kind of like the holy grail

Of understanding how galaxies evolve.

Narrator: Maybe the answer to how supermassive black holes formed

Can be found in the life and death of other black holes.

Because we've long known that supermassive black holes

Have a tiny relative --

Stellar black holes.

And unlike their supermassive cousins,

We do know how these tiny stellar black holes form.

Stellar-mass black holes form when a massive star dies.

The core collapses into this super-dense object

That we call a black hole.

The core might have three or five

Or 10 times the mass of the sun.

And that's why they are stellar-mass black holes.

They have about the mass of a star.

Narrator: When a huge star dies in a dramatic supernova explosion,

All that's left is the dense remnants of the star's core,

Crammed into a minuscule point in space --

A stellar black hole.

Imagine that a star like the sun

Can shrink down to essentially a pinhead size.

It sounds wild and crazy and like science fiction.

But it's science reality.

Narrator: If collapsing stars form stellar black holes,

Could their supermassive cousins have formed this way, too?

It's a neat idea, but there's a problem.

Stellar black holes may weigh in

At several times the mass of our sun,

But they're a million times smaller.

That means they're dwarfed

By the monstrous supermassive black holes.

Supermassive black holes can be

As big as an entire solar system.

No single star could ever be big enough

To collapse into a monster black hole this size.

The challenge for scientists is to figure out

How the universe created black holes

That are billions of times more massive than the sun.

One theory is that

Perhaps supermassive black holes weren't born big.

Instead, they may have grown from smaller black holes

Merging with each other.

Theorists have long predicted that

Black holes should be able to merge.

But astronomers need observations to prove it's true.

In the heart of the idyllic italian countryside

Sits a machine designed to detect

The far-off murmurs of black holes merging.

This is virgo.

Here, scientists monitor the cosmos 24/7,

Hunting for black holes.

Walter del pozzo is a theorist on the team.

Del pozzo: What I do is trying to understand

What black holes are and how they work

And how they grow, how they evolve.

I love the challenge of trying

To understand how the universe work.

Narrator: Walter wants to use virgo

To do something that was once thought impossible.

He hopes to detect black holes growing.

Walter believes that if one black hole merges with another,

The violence of this event should send tell-tale ripples

Out through the fabric of space...

...Just like the ripples in a pond.

Physicists call these ripples gravitational waves.

It was once thought that they'd be too small to detect.

But then machines like virgo came along.

Virgo consists of not one

But two two-mile-long pipes forming an l shape.

These pipes are the most sensitive

Measuring devices on earth.

A laser is shot along these two right-angle lines.

They travel all the way to the end.

They bounce on a mirror.

They come back.

This makes these two arms

A very, very, very sensitive ruler,

Which we can use to detect tiny changes in the distances.

Narrator: If a gravitational wave from merging black holes

Passes through virgo's two pipes,

It could compress and expand first one pipe then the other --

Changes in length walter hopes to measure.

Those changes are really, really tiny.

This is why we need those huge, huge rulers --

To be able to detect those tiny, tiny, tiny changes.

[ alarm blaring ]

Narrator: These lasers can detect

These two-mile-long pipes changing length

By a billionth of the width of a human hair.

And in August 2017,

These super-sensitive instruments

Allow walter and the team to witness something extraordinary.

They detect the unmistakable ripple

Of two black holes merging.

Del pozzo: Virgo has been a great success indeed.

What we are seeing here is the deadly dance of two black holes.

They get closer and closer.

And from here, we can actually tell

That the final object was a black hole.

This whole process that we registered

Lasted a fraction of a second.

Walter's reading is the ripple of an event

That took place one billion years ago in a distant galaxy.

Two black holes approach each other --

One 25 times more massive than our sun,

The other -- 30.

They enter into a death spiral.

The two black holes accelerate

To almost half the speed of light,

Until finally, they collide,

Leaving behind a single, much heavier black hole.

It takes a billion years for the ripples from this

Black hole merger to reach the virgo detector on earth.

This is a major breakthrough.

Virgo and similar machines in the u.S. Have finally proven

That black holes can grow by merging together.

We were the first ones in history

To be able to see two black holes eating each other

And merging to become a single black hole.

That's incredible, okay. [laughs]

Narrator: And by measuring gravitational waves,

Astronomers get their first taste

Of an immensely powerful new tool

For understanding the cosmos.

Tremblay: Now we have a fundamentally new window in the universe.

That's not collecting light.

That's listening to the music of the cosmos.

And it is an absolutely transformational new way

To look at the universe.

Narrator: So, is it case closed?

Do smaller stellar black holes merge together

To form supermassive black holes?

Unfortunately, it seems unlikely.

And if not, then how did

Supermassive black holes grow so big?

Scientists might be on the verge of an answer.

♪

Narrator: Scientists are on a mission to discover

How the monstrous supermassive black holes

That lurk in the centers of galaxies formed.

Some of them are ancient, born when the universe

Was just a few hundred-million years old.

That's far too short a time for billions of smaller

Stellar black holes to have formed and then merged together.

If you start with something that has

Five times the mass of the sun,

How long does it take

To get to a billion times the mass of the sun?

And it turns out, yeah, the age of the universe.

It takes billions of years.

The idea that supermassive black holes

Started off as stellar-mass black holes that then grew

Doesn't seem plausible.

Narrator: So, if supermassive black holes

Couldn't have formed from smaller stellar black holes

Merging together, how did they grow so big?

The leading theory is that the early universe

Must have cooked up a third category of black hole

Smaller than today's supermassive beasts,

But still much bigger than the stellar black holes

Formed by collapsing stars.

There must be another kind of black hole

That we haven't found yet,

A black hole that's kind of in the middle,

Something like maybe a couple thousand times

The mass of the sun.

We call these seed black holes.

Narrator: They're called seed black holes

Because scientists believe that

Supermassive black holes grow from them.

These seeds are much bigger than

The black holes formed by collapsing stars.

So it wouldn't take very many of them

Or very long to merge together and grow supermassive.

The underlying logic here is actually really simple.

If you wanna build a really big black hole,

You need bigger building blocks.

Narrator: If the early universe cooked up these seed black holes,

There should be still plenty of them around today --

Seed black holes that have yet to be swallowed up

By the supermassive black holes.

And that's a problem, because we can't find them.

They're missing.

We've discovered many black holes,

But they come in these two size categories,

One a few times the mass of the sun,

And the other's millions or billions

Of times the mass of the sun.

What about all the ones that should be in between there?

We haven't seen those.

Thaller: One of the holy grails in astronomy right now

Is to find one of these seed black holes.

If they're not out there, we have to reevaluate

Everything we know about the evolution of the universe.

Narrator: Investigators have yet to find a confirmed seed black hole.

But is that about to change?

Mar mezcua is on the hunt for these middleweight monsters.

Finding black holes in the dark of space is no simple task.

Nothing can escape from a black hole, not even light.

Therefore, black holes are black.

They do not emit light.

So how do we detect them?

Narrator: Black hole hunting requires a special kind of telescope.

Mar comes to medicina observatory in northern Italy.

Here, they don't look at the universe in visible light.

They look at radio waves.

One way to observe black holes is to use radio astronomy.

Using radio telescopes, we get a different view of the universe,

A different view of galaxies and black holes.

Narrator: Radio waves are a form of light humans can't see.

But unlike visible light,

Radio waves emitted by objects in space

Can pierce the dust and gas scattered around the universe.

We can even observe radio waves during the day.

This allows mar to see that something odd is going on

In galaxy ngc 2276,

A galaxy 100 million light years from earth.

Could it be home to a seed black hole?

[dramatic orchestral music]

At first glance, the galaxy doesn't look too special.

So, this here is a very nice image

Taken with the hubble space telescope.

That's the galactic center,

Where the supermassive black hole should reside.

And then these are the spiral arms,

Where lots of stars are being formed.

Narrator: But look closer, and there appears

To be a mysterious dark patch in one of the spiral arms.

So we think that in this darker area here,

There's no dust and there's no gas able to create the stars.

And that's why no stars are being formed.

So something must have cleared the gas.

Narrator: What strange forces can clear out

A huge patch of dust and stars?

Mar looks at the galaxy in radio waves.

She sees something astonishing.

A radio bright spot.

Mezcua: What we are seeing here is radio emission

From a location in the spiral arm of ngc 2276.

The radio emission that we detect

Is located right here in this dark region.

Narrator: Mar thinks this radio bright spot can only be one thing.

Blasting a hole in the side of the galaxy

Reveals the scale of the void.

It's enormous and almost completely devoid of stars.

The reason lies within -- a jet of intense radiation.

Like a galactic blowtorch,

It's blasted away the star-forming gas.

Traveling six light years along the jet

Leads to the heart of the void

And the ultimate source of the radiation --

A black hole gorging itself on a vortex of cosmic dust.

As it feeds, the black hole

Whips the dust around it into a frenzy,

Blasting out scorching beams of intense radiation.

But could this just be a small stellar black hole

With a mass of a few times that of our sun?

It seems unlikely.

Because of the size of this dark region,

We know that it cannot be a stellar black hole.

It must be something bigger.

Narrator: And if this were a supermassive black hole

Weighing a few million times the mass of the sun,

It would be at the center of its galaxy,

Not here on the outskirts.

Could this be a seed black hole,

The missing link that can help tell us

How supermassive black holes and galaxies form?

♪

Narrator: At the medicina observatory in northern Italy,

Astrophysicist mar mezcua could be on the verge

Of a breakthrough discovery.

Using radio telescopes, she looks at galaxy ngc 2276

And sees something remarkable,

A bright spot of intense radiation

That could only be caused by one thing: A black hole.

Could it be a seed black hole?

We have used radio observations of this black hole,

Together with x-ray measurements,

To estimate the black hole mass.

And we find that this black hole has a mass

Of more than 10,000 times the mass of the sun.

Narrator: That puts this black hole

Firmly in the middleweight division.

It looks like this really is a seed black hole.

This is a source that warrants

Really urgent observational follow-up.

Because it very well may be a seed black hole.

And this is really cool,

Because we don't have really firm evidence of these things.

Narrator: If mar is right,

Seed black holes really do exist.

It's a huge breakthrough in our understanding

Of how supermassive black holes and galaxies grow.

But it's not a confirmed find yet,

And other scientists are hot on her heels.

At mcdonald observatory in texas,

Eva noyola is on the trail

Of another middleweight contender.

Her potential seed black hole

Sits right in our galaxy's backyard.

Eva investigates star clusters.

Star clusters are these collection of stars

That are gravitating around each other independently,

And they tend to orbit around galaxies.

So they can go from 10,000 stars only to millions of stars.

Narrator: Around 200 large star clusters orbit the milky way,

And eva thinks inside them, we may find seed black holes.

Eva has found one cluster, omega centauri,

That behaves particularly strangely.

Omega centauri is the largest star cluster around the galaxy.

It's roughly a spherical shape,

And it's about two million stars.

The density of stars is so high

That compared to our solar neighborhood,

The stars are a thousand times closer.

That's where things are harder to measure,

Because there are so many stars near to each other,

But it's very hard to tell them apart.

Narrator: Eva thinks that a monster lurks

At the heart of this dense cluster of stars.

There's something creating gravitational pull,

But it's not visible.

Right there in the middle. [chuckles]

Narrator: Eva carefully observes

How the stars inside the cluster move through space

And finds something astonishing.

Noyola: The speed of the stars in the very center of the cluster

Is about four times faster than the speed at the outskirts.

So it's a pretty big increase.

Narrator: Something small but with a huge amount of gravity

Seems to be whipping the stars in the cluster's center

Into a frenzy.

But no matter how hard eva looks,

She can't see this object.

Noyola: You have a very massive, very compact object

That does not give off light.

This thing essentially jumped at me.

Narrator: If eva's right, for billions of years,

Omega centauri has been hiding a dark secret.

Deep inside, stars hurdle through space on overdrive,

Many times faster than they should.

Only a dense object with immense gravity

Can pull stars into orbits like this --

A black hole.

And judging by the sheer speeds of the stars in its grasp,

This is no small stellar black hole.

It's a seed black hole.

My heart rate just elevated

Because it was so exciting to see.

It was very clear that there was something very interesting there.

Narrator: This seed isn't feeding,

So it's not producing radio waves.

But by measuring the speeds of the stars orbiting around it,

Eva can still calculate how big it is.

Noyola: The size of the black hole that is the best fit

Is 50,000 times the mass of the sun.

It is right between the little stellar-mass black holes,

Which are a lot smaller,

And the supermassive black holes,

Which are much, much bigger.

The fact that it's in the middle

Is what makes it a seed black hole.

Narrator: Weighing in at 50,000 times the mass of the sun,

This is five times heavier

Than mar mezcua's black hole

But still firmly within the seed black hole weight division.

But what makes eva's seed even more intriguing

Is the cluster of stars that hang around it

Like moths around a flame.

Could this entourage of stars be a clue to how galaxies

Like the milky way first formed in the early universe?

And can this strange glow from the galactic center

Reveal that our own supermassive black hole

Is still growing fat on a diet of these seeds?

Oluseyi: These seed black holes may exist in our galaxy today.

Maybe they're in our own cosmic backyard.

♪

♪

Narrator: Astronomers are on the verge of a breakthrough.

They've found evidence that middleweight

Seed black holes really do exist.

And one seed black hole in particular

Has astronomers excited, because clustered around it

Is a bunch of stars, like a mini galaxy.

It hints at an astonishing history for these middleweights.

Seed black holes and the stars they drag with them

Could have helped build

The vast collections of stars we call galaxies.

A clue to their galaxy-building role

Lies inside the central bulge of the milky way.

The stars inside the bulge

Resemble those in the star clusters

Thought to be home to seed black holes.

Noyola: The population at the center of galaxies

In galactic bulges really matches

Very well the population of the star clusters.

So we know that a lot of the bulge is made of those stars.

Narrator: If the centers of galaxies

Are largely built from these star clusters,

This suggests an extraordinary role for seed black holes.

13 billion years ago,

The universe didn't have large spiral galaxies

Like the milky way.

Instead, it may have been filled with seed black holes,

Each with a disorganized mass of stars around it.

It's from these ingredients that scientists think galaxies grew.

Seed black holes could act as anchors

For the stars that swarm around them,

And those anchors could find one another in the void of space

And coalesce to form a larger galaxy.

Narrator: With seed black holes as the catalyst,

We can imagine how the milky way formed.

Two star clusters collide.

Their stars are pulled out of orbit and chaotically mix.

In the thick of the action, two seed black holes face off,

Circling each other in a deadly dance.

They finally fuse to form a bigger black hole.

The increased gravity sucks in more material

And pulls more star clusters into the fray,

Until eventually the seeds had ballooned...

...Into a supermassive black hole.

And around this monster, the stars from those clusters

Helped to form our galaxy, the milky way.

I find it amazing that these little star clusters

That are old and tiny

End up being these fantastic archeological objects

That end up being the building blocks

Of the galaxies that we observe everywhere in the universe.

Narrator: The theory that seed black holes

Helped build the milky way is an exciting one.

But where's the proof?

Scientists scour the hearts of galaxies

For evidence of seed black holes.

The holy grail is now to find stray seed black holes

That are still in the process of merging.

In southern arizona sits a unique set of telescopes.

This is veritas.

Veritas is made up of four dishes,

Each 40 feet across with 350 hexagonal mirrors apiece.

These bizarre-looking instruments

Are designed to look for a special form

Of intense, high-energy light called gamma rays.

John quinn believes gamma ray telescopes like these

Could offer up a brand-new way to hunt for seed black holes.

Veritas is a ground-based gamma ray observatory.

It lets us study sources of what are known

As very high-energy gamma rays,

Gamma rays a million-million times more energetic than light,

Way higher than anything we can produce

In any laboratory on earth.

It leaves a very sharp image

Of the gamma rays when they come in.

Narrator: Gamma rays are light waves on steroids

Created by the most extreme objects in the cosmos --

Violently spinning pulsars...

...Exploding supernovae...

...And enormous quasars...

All fire out gamma rays.

And when these high-energy waves hit earth,

They tear through the atmosphere,

Creating bursts of blue light.

These bursts are normally invisible,

But veritas can see them.

Here, we're seeing various events.

Each change you see is 2,000 millionths of a second.

We have to use specialized detectors,

High-speed electronics to detect these.

Narrator: And gamma ray astronomy

Has thrown scientists a stunning curve ball,

One that could provide the proof

That seed black holes helped build the galaxy.

Investigators discovered that the center of our galaxy

Emits an unexplained gamma ray glow.

This is the entire gamma ray sky.

The plane of the galaxy is along the center,

And we can see the center of the galaxy here.

Narrator: This central region fires out

Many more gamma rays than it should.

And we currently don't understand what is causing this.

Plait: Gamma rays are a form of light that's pretty hard to produce.

You need to have a huge energetic source to make them.

So we expected to see some coming

From the center of the galaxy.

That's a lot of activity going on there.

The problem is we're seeing too many.

Our milky way is overproducing.

There's an excess of gamma rays coming from there.

Why?

Narrator: Could thousands of seed black holes

Orbit the supermassive black hole

At the heart of the milky way,

Emitting gamma rays as they circle the galactic center?

Quinn: It is possible that some of the gamma ray events

That we're seeing are produced from seed black holes

In the vicinity of the galactic center.

Narrator: But how can black holes produce radiation

If nothing ever escapes their gravitational pull,

Not even light?

The answer could lie in the cosmic debris that they feed on.

Matter is attracted towards the seed black hole

By its enormous gravity,

And as the black hole spins,

Its gravity whips the matter into a frenzy,

Generating huge amounts of energy,

Which blasts out from the area around the black hole

In a bright beacon of radiation

And perhaps even gamma rays.

Could this be the explanation for the mysterious glow

Coming from the heart of the milky way?

Could it be seed black holes?

Gamma rays could be the observable beacons

For otherwise unobservable seed black holes.

And that would be an absolutely transformational discovery.

♪

♪

Narrator: If the mysteriously glowing galactic center

At the heart of our milky way is thanks to seed black holes,

It would be an astonishing discovery.

It would tell us

Our supermassive black hole isn't alone.

There could be seed black holes orbiting it --

Seeds that, billions of years ago,

Delivered the stars that helped build the milky way.

That would really help fill in the story

Fill in the puzzle of how structure in the universe forms.

Narrator: It would be the final proof

That seed black holes helped build our galaxy.

We may even be lucky enough to find that

Our supermassive black hole is still merging with these seeds.

There could be see black holes still in our galaxy today.

Our supermassive black hole may still be feeding on them.

Narrator: And with each collision,

Our supermassive black hole becomes even more massive.

♪

Seed black holes could turn out to be

The most important objects in the universe --

A cosmic game changer.

But one mystery remains unsolved.

If these seed black holes are so important

To the story of our universe,

Where did they come from?

In austin, texas, volker bromm knows how difficult it is

To make seed black holes.

That's because volker tries to make his own seed black holes

Inside this vast supercomputer, stampede.

What we see here is one of the most powerful

Supercomputers on planet earth.

Supercomputers like this allow us to basically take

The laws of nature and create a sophisticated computer code

And then let the computer advance the universe

Over billions of years in time.

Narrator: In short, volker is creating a simulation

Of the early universe inside a computer.

He wants to investigate

How nature could've cooked up these crucial seed black holes.

A few million years after the big bang,

We had a very boring universe.

What cosmologists call the dark ages.

In the dark ages, there were no sources of light --

No stars, no galaxies, no black holes.

Narrator: The early universe contained simple clouds of gas.

Volker suspects these giant clouds collapsed

To form the biggest stars the universe has ever seen,

Perhaps hundreds of thousands of times more massive than our sun.

These supergiant stars quickly collapsed

To form seed black holes,

But volker's early simulations

Reveal a problem with the theory.

His virtual stars always explode

Before they grow big enough to form a seed black hole.

So here we see a massive star dying, exploding,

Putting in a bubble of high-energy radiation.

This energy input basically drives the gas out again.

And this limits the ability of the gas to collapse

And eventually to end up in a black hole.

Narrator: The virtual stars run out of fuel too quickly and explode.

Bromm: Stars are producers of energy.

They eventually explode,

And they create outward-acting pressure.

Narrator: The explosions stop the gas cloud collapsing further,

And although the dying stars in the simulation

Do form black holes,

They're much smaller than the seed black holes

That helped build the galaxies we see today.

Volker needs a new recipe,

One that'll make an enormous cloud of gas

Collapse to form a single massive star,

Not thousands of smaller ones.

It's possible that in the early universe

Conditions were very different.

Instead of clouds forming beautiful little star clusters,

Giant clouds of dust and gas all collapsed at once.

If conditions are just right, that gas can collapse

All the way down into a very massive seed.

Narrator: But what are these conditions?

Volker realizes that there is a magic ingredient

That could allow seed black holes to form.

♪

♪

Narrator: Cosmologists believe the galaxies we see today

And the supermassive black holes at their hearts

Were formed in the early universe

By middleweight seed black holes merging together,

But how did these seed black holes form?

It might come down to one ingredient.

The mysterious substance -- dark matter.

We now understand that galaxies are really dominated

By a form of matter we can't see.

We know it's there by its gravity,

But there's no other signal from it at all.

It's what we call dark matter.

Narrator: Dark matter, despite being invisible,

Could allow seed black holes to form

Because one thing we do know about dark matter

Is that it has a gravitational pull.

The really interesting spots

Are where we have these bright patches.

This is where dark matter has assembled,

And the dark matter then provides gravity.

And this gravity is able to attract gas that is quite hot.

Narrator: Volker runs new simulations.

He fine tunes the conditions

To produce a new virtual universe,

And inside this universe, the pull of dark matter

Overcomes the energy that had previously prevented collapse.

Here we see primordial gas

Falling into the center of the dark matter structure,

And the gravity of the dark matter is so strong

That it can overcome all opposing forces.

Narrator: As more and more gas rushes in,

Volker's simulation produces a huge spinning cosmic tornado.

And this motion allows the gas to be funneled,

To be concentrated in the center.

Narrator: And over time, the tornado grows.

We start with 10 times the mass of the sun.

Eventually it goes to 100 times, a 1,000 times,

100,000 times the mass of the sun.

It was not clear that this would be possible

And we was rather, in awe if you like.

In a way, it's so beautiful

That you almost are tempted to fall in love with it.

Narrator: When so much gas funnels into one point in space,

You can create a star like nothing we've ever seen before.

If the simulation is right, in the early universe

Dark matter filaments draw cosmic gas into colossal clouds

Bigger than a galaxy.

Inside the clouds, the temperature's rocket

Until conditions are so extreme

That in the center, colossal blue stars

Maybe 100,000 times bigger than the sun

Burst into life.

But they consume fuel at hellish speeds,

And their cores begin to collapse.

A colossal quantity of material

Crushes down to a point in space...

Creating an enormous seed black hole.

If we have a lot of gas that's in the right configuration

Allowing it to all fall together in just the right way

That it gets small enough, then it would turn into

A black hole of absolutely any size that you want.

So the black hole is instead of being born an infant

It's like being born an adolescent.

It's already very massive.

This can put into place a black hole in one go

Already with a mass of about a 100,000 times

The mass of the sun, maybe up to a million.

Those conditions were really very rare.

And they only happened in select regions in the universe.

And it's almost, you could say, a kind of cosmic miracle.

Narrator: If volker's right,

The seed black holes we find today

Are almost as old as the universe itself --

The last remaining survivors of an ancient breed of objects.

Tremblay: They could be relics of a very, very, very,

Narrow window of time in the very early universe,

Which means they would be very old, right?

Way older than we think.

Narrator: And their brothers and sisters merge

To help build the supermassive black holes we see today,

Helping create the galaxy we call home

And bringing structure to the universe.

With this formation theory for seed black holes,

The story is complete.

The huge seed black holes that form from the gas clouds

In the early universe gather stars around them.

These giant seeds merge and feed

To grow into the monstrous supermassive black holes

That hold billions of stars in orbit,

Ultimately giving us giant galaxies

Like our home, the milky way.

In a way, the only reason you're sitting here right now

Is that seed black holes, a long time ago,

Gathered the material

To make galaxy and star formation possible.

Narrator: We may not have a confirmed seed yet,

But scientists are close.

There's gonna come a time when we have sort of the smoking gun.

And it's like, "here it is. Here is a seed black hole."

And when we do that, that's fantastic,

Because that is a puzzle piece

That goes into the jigsaw puzzle of the universe

And makes a more complete picture

Of what we know is out there.

That's pretty exciting.

Think about how much a breakthrough

That moment will be.

We have based our entire idea

About how galaxies form, how stars form,

Eventually how planets and you and I form on the idea that

Seed black holes were there in the distant past,

Beginning to grow galaxies themselves.

I think it's some of the most exciting times right now

In black hole astrophysics,

And we just can't wait to see what's next.

Narrator: And once we know for sure seed black holes are out there,

We'll have the final chapter

In the story of how the universe we see today

Came to be.