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Narrator:
Supermassive black holes --
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Gargantuan monsters that lurk
at the center of galaxies.
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Right now you are traveling at
half a million miles an hour
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Around a giant black hole
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Four million times
the mass of the sun.
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Narrator: But there's a mystery
about these colossal beasts.
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We have no idea
where they came from.
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How did they get
so big so quickly?
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We know they weren't "born"
or created that way.
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It doesn't make sense.
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Narrator: Today,
investigators are seeing
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Tantalizing glimpses of an
entirely new type of black hole.
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This thing essentially
jumped at me.
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Narrator: Could this
new breed of black hole
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Be the seeds that built
the supermassive monsters?
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It is almost a kind
of cosmic miracle.
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Narrator:
And might they even hold a clue
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To how the milky way
itself formed?
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Oluseyi: It sounds crazy
and like science fiction,
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But it's science reality.
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Narrator: The race is on
to find the missing link
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That will reveal how
supermassive black holes
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And the galaxies around them
were created.
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I would say this is the golden
age of black hole physics.
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Narrator:
This is the final chapter
in our cosmic creation story.
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♪
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-- Captions by vitac --
www.Vitac.Com
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Captions paid for by
discovery communications
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At the very heart of every
large galaxy lurks a monster --
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A supermassive black hole.
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These are the undisputed
heavyweight champions
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Of the cosmos.
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There's a trillion galaxies
in the observable universe,
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And each one has a supermassive
black hole in its center.
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Narrator: Supermassive black
holes can weigh
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As much as six billion suns,
and all that matter
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Is packed into
a tiny point in space.
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They'll suck in anything
that strays too close.
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Planets, stars,
not even light can escape.
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A black hole is a
bottomless pit of gravity
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That actually draws in
material all around it.
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Plait: If you get too close,
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There is no force
in the universe
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That you can apply to
yourself to get back out.
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Narrator:
But as well as being the
ultimate agents of destruction,
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Supermassive black holes
bring order to the universe.
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Their colossal gravity
corrals countless stars
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Into orbit around them,
forming the hearts of galaxies.
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Plait: We think
that the galaxy itself
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Depends on that supermassive
black hole for its structure.
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If these things didn't exist,
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Galaxies would look
completely different.
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Narrator:
But a big mystery surrounds
supermassive black holes.
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We have no idea
where they came from.
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How does the universe compress
the mass of six billion stars
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Into a single point in space?
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The answer won't just tell us
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How supermassive
black holes form.
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It may reveal how the galaxies
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That fill the universe
came to exist, too.
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If we can understand how
supermassive black holes grow,
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Then that's kind of like
the holy grail
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Of understanding
how galaxies evolve.
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Narrator:
Maybe the answer to how
supermassive black holes formed
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Can be found in the life
and death of other black holes.
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Because we've long known
that supermassive black holes
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Have a tiny relative --
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Stellar black holes.
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And unlike their
supermassive cousins,
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We do know how these tiny
stellar black holes form.
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Stellar-mass black holes form
when a massive star dies.
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The core collapses
into this super-dense object
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That we call a black hole.
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The core might
have three or five
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Or 10 times the mass of the sun.
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And that's why they are
stellar-mass black holes.
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They have about
the mass of a star.
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Narrator:
When a huge star dies in
a dramatic supernova explosion,
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All that's left is the dense
remnants of the star's core,
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Crammed into a minuscule
point in space --
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A stellar black hole.
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Imagine that a star like the sun
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Can shrink down to
essentially a pinhead size.
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It sounds wild and crazy
and like science fiction.
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But it's science reality.
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Narrator: If collapsing stars
form stellar black holes,
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Could their supermassive cousins
have formed this way, too?
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It's a neat idea,
but there's a problem.
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Stellar black holes
may weigh in
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At several times
the mass of our sun,
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But they're
a million times smaller.
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That means they're dwarfed
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By the monstrous
supermassive black holes.
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Supermassive black holes can be
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As big as an entire
solar system.
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No single star could
ever be big enough
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To collapse into a monster
black hole this size.
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The challenge for
scientists is to figure out
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How the universe
created black holes
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That are billions of times
more massive than the sun.
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One theory is that
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Perhaps supermassive black holes
weren't born big.
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Instead, they may have grown
from smaller black holes
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Merging with each other.
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Theorists have
long predicted that
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Black holes should
be able to merge.
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But astronomers need
observations to prove it's true.
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In the heart of the idyllic
italian countryside
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Sits a machine
designed to detect
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The far-off murmurs
of black holes merging.
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This is virgo.
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Here, scientists
monitor the cosmos 24/7,
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Hunting for black holes.
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Walter del pozzo
is a theorist on the team.
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Del pozzo: What I do
is trying to understand
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What black holes are
and how they work
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And how they grow,
how they evolve.
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I love the challenge of trying
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To understand
how the universe work.
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Narrator:
Walter wants to use virgo
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To do something that was
once thought impossible.
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He hopes to detect
black holes growing.
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Walter believes that if one
black hole merges with another,
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The violence of this event
should send tell-tale ripples
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Out through the fabric
of space...
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...Just like
the ripples in a pond.
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Physicists call these
ripples gravitational waves.
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It was once thought that
they'd be too small to detect.
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But then machines
like virgo came along.
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Virgo consists of not one
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But two two-mile-long pipes
forming an l shape.
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These pipes
are the most sensitive
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Measuring devices on earth.
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A laser is shot along
these two right-angle lines.
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They travel all
the way to the end.
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They bounce on a mirror.
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They come back.
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This makes these two arms
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A very, very, very
sensitive ruler,
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Which we can use to detect
tiny changes in the distances.
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Narrator:
If a gravitational wave
from merging black holes
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Passes through virgo's
two pipes,
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It could compress and expand
first one pipe then the other --
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Changes in length
walter hopes to measure.
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Those changes are
really, really tiny.
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This is why we need
those huge, huge rulers --
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To be able to detect those
tiny, tiny, tiny changes.
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[ alarm blaring ]
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Narrator: These lasers
can detect
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These two-mile-long
pipes changing length
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By a billionth
of the width of a human hair.
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And in August 2017,
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These super-sensitive
instruments
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Allow walter and the team to
witness something extraordinary.
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They detect
the unmistakable ripple
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Of two black holes merging.
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Del pozzo: Virgo has been
a great success indeed.
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What we are seeing here is the
deadly dance of two black holes.
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They get closer and closer.
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And from here,
we can actually tell
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That the final object
was a black hole.
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This whole process
that we registered
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Lasted a fraction of a second.
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Walter's reading
is the ripple of an event
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00:09:04,278 --> 00:09:10,815
That took place one billion
years ago in a distant galaxy.
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Two black holes
approach each other --
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One 25 times more massive
than our sun,
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The other -- 30.
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They enter into a death spiral.
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The two black holes accelerate
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To almost half
the speed of light,
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Until finally,
they collide,
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Leaving behind a single,
much heavier black hole.
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It takes a billion years
for the ripples from this
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Black hole merger to reach
the virgo detector on earth.
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This is a major breakthrough.
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Virgo and similar machines
in the u.S. Have finally proven
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That black holes can
grow by merging together.
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We were the first
ones in history
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To be able to see two black
holes eating each other
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And merging to become
a single black hole.
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That's incredible,
okay. [laughs]
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Narrator: And by measuring
gravitational waves,
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Astronomers get
their first taste
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00:10:18,919 --> 00:10:21,119
Of an immensely
powerful new tool
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00:10:21,121 --> 00:10:24,089
For understanding the cosmos.
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00:10:24,091 --> 00:10:28,026
Tremblay:
Now we have a fundamentally
new window in the universe.
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That's not collecting light.
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That's listening
to the music of the cosmos.
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00:10:31,698 --> 00:10:34,599
And it is an absolutely
transformational new way
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00:10:34,601 --> 00:10:35,900
To look at the universe.
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Narrator: So, is it case closed?
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Do smaller stellar
black holes merge together
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00:10:41,608 --> 00:10:44,743
To form supermassive
black holes?
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00:10:44,745 --> 00:10:47,579
Unfortunately,
it seems unlikely.
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00:10:47,581 --> 00:10:49,914
And if not, then how did
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00:10:49,916 --> 00:10:53,051
Supermassive black holes
grow so big?
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00:10:53,053 --> 00:10:57,722
Scientists might be on
the verge of an answer.
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♪
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00:11:15,375 --> 00:11:18,176
Narrator: Scientists
are on a mission to discover
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00:11:18,178 --> 00:11:21,279
How the monstrous
supermassive black holes
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00:11:21,281 --> 00:11:24,416
That lurk in the centers
of galaxies formed.
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00:11:24,418 --> 00:11:27,619
Some of them are ancient,
born when the universe
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00:11:27,621 --> 00:11:30,855
Was just a few
hundred-million years old.
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00:11:30,857 --> 00:11:33,758
That's far too short a time
for billions of smaller
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00:11:33,760 --> 00:11:37,929
Stellar black holes to have
formed and then merged together.
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00:11:37,931 --> 00:11:39,597
If you start
with something that has
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00:11:39,599 --> 00:11:41,099
Five times the mass of the sun,
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00:11:41,101 --> 00:11:42,333
How long does it take
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00:11:42,335 --> 00:11:45,270
To get to a billion times
the mass of the sun?
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00:11:45,272 --> 00:11:47,906
And it turns out, yeah,
the age of the universe.
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00:11:47,908 --> 00:11:49,307
It takes billions of years.
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00:11:50,343 --> 00:11:52,377
The idea that
supermassive black holes
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00:11:52,379 --> 00:11:56,247
Started off as stellar-mass
black holes that then grew
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00:11:56,249 --> 00:11:57,882
Doesn't seem plausible.
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00:11:57,884 --> 00:12:00,452
Narrator: So,
if supermassive black holes
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00:12:00,454 --> 00:12:03,354
Couldn't have formed from
smaller stellar black holes
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00:12:03,356 --> 00:12:07,025
Merging together,
how did they grow so big?
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00:12:07,027 --> 00:12:09,828
The leading theory
is that the early universe
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00:12:09,830 --> 00:12:13,064
Must have cooked up a third
category of black hole
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00:12:13,066 --> 00:12:16,101
Smaller than today's
supermassive beasts,
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00:12:16,103 --> 00:12:19,504
But still much bigger
than the stellar black holes
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00:12:19,506 --> 00:12:21,673
Formed by collapsing stars.
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00:12:21,675 --> 00:12:24,042
There must be another
kind of black hole
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00:12:24,044 --> 00:12:25,610
That we haven't found yet,
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00:12:25,612 --> 00:12:27,345
A black hole that's
kind of in the middle,
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00:12:27,347 --> 00:12:29,347
Something like maybe
a couple thousand times
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00:12:29,349 --> 00:12:30,415
The mass of the sun.
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We call these seed black holes.
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00:12:33,820 --> 00:12:36,321
Narrator: They're called
seed black holes
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00:12:36,323 --> 00:12:38,289
Because scientists believe that
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00:12:38,291 --> 00:12:41,326
Supermassive black
holes grow from them.
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00:12:42,863 --> 00:12:44,963
These seeds are much bigger than
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00:12:44,965 --> 00:12:47,766
The black holes formed
by collapsing stars.
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00:12:47,768 --> 00:12:50,168
So it wouldn't take
very many of them
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00:12:50,170 --> 00:12:54,839
Or very long to merge together
and grow supermassive.
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00:12:54,841 --> 00:12:57,275
The underlying logic here
is actually really simple.
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00:12:57,277 --> 00:12:59,244
If you wanna build
a really big black hole,
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00:12:59,246 --> 00:13:01,679
You need bigger building blocks.
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00:13:01,681 --> 00:13:05,350
Narrator:
If the early universe cooked up
these seed black holes,
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00:13:05,352 --> 00:13:08,353
There should be still
plenty of them around today --
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00:13:08,355 --> 00:13:11,523
Seed black holes that have
yet to be swallowed up
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00:13:11,525 --> 00:13:13,758
By the supermassive black holes.
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00:13:15,128 --> 00:13:18,263
And that's a problem,
because we can't find them.
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00:13:18,265 --> 00:13:20,465
They're missing.
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00:13:20,467 --> 00:13:22,433
We've discovered
many black holes,
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00:13:22,435 --> 00:13:25,203
But they come in these
two size categories,
248
00:13:25,205 --> 00:13:27,705
One a few times
the mass of the sun,
249
00:13:27,707 --> 00:13:29,541
And the other's
millions or billions
250
00:13:29,543 --> 00:13:31,209
Of times the mass of the sun.
251
00:13:31,211 --> 00:13:33,645
What about all the ones that
should be in between there?
252
00:13:33,647 --> 00:13:35,814
We haven't seen those.
253
00:13:35,816 --> 00:13:37,916
Thaller: One of the holy grails
in astronomy right now
254
00:13:37,918 --> 00:13:39,884
Is to find one of
these seed black holes.
255
00:13:39,886 --> 00:13:42,320
If they're not out there,
we have to reevaluate
256
00:13:42,322 --> 00:13:45,590
Everything we know about
the evolution of the universe.
257
00:13:45,592 --> 00:13:50,428
Narrator:
Investigators have yet to find
a confirmed seed black hole.
258
00:13:50,430 --> 00:13:53,264
But is that about to change?
259
00:13:53,266 --> 00:13:56,968
Mar mezcua is on the hunt
for these middleweight monsters.
260
00:13:56,970 --> 00:14:01,739
Finding black holes in the dark
of space is no simple task.
261
00:14:03,677 --> 00:14:06,377
Nothing can escape from
a black hole, not even light.
262
00:14:06,379 --> 00:14:08,012
Therefore,
black holes are black.
263
00:14:08,014 --> 00:14:09,781
They do not emit light.
264
00:14:09,783 --> 00:14:12,383
So how do we detect them?
265
00:14:12,385 --> 00:14:16,487
Narrator:
Black hole hunting requires
a special kind of telescope.
266
00:14:18,024 --> 00:14:21,826
Mar comes to medicina
observatory in northern Italy.
267
00:14:21,828 --> 00:14:25,230
Here, they don't look at
the universe in visible light.
268
00:14:25,232 --> 00:14:27,932
They look at radio waves.
269
00:14:27,934 --> 00:14:30,935
One way to observe black holes
is to use radio astronomy.
270
00:14:32,038 --> 00:14:35,373
Using radio telescopes, we get a
different view of the universe,
271
00:14:35,375 --> 00:14:38,076
A different view of galaxies
and black holes.
272
00:14:40,213 --> 00:14:44,716
Narrator: Radio waves are a form
of light humans can't see.
273
00:14:44,718 --> 00:14:46,384
But unlike visible light,
274
00:14:46,386 --> 00:14:49,087
Radio waves emitted
by objects in space
275
00:14:49,089 --> 00:14:52,891
Can pierce the dust and gas
scattered around the universe.
276
00:14:54,261 --> 00:14:57,762
We can even observe
radio waves during the day.
277
00:14:58,798 --> 00:15:02,066
This allows mar to see
that something odd is going on
278
00:15:02,068 --> 00:15:06,037
In galaxy ngc 2276,
279
00:15:06,039 --> 00:15:09,173
A galaxy 100 million
light years from earth.
280
00:15:10,310 --> 00:15:12,844
Could it be home to
a seed black hole?
281
00:15:12,846 --> 00:15:16,547
[dramatic orchestral music]
282
00:15:18,652 --> 00:15:22,253
At first glance, the galaxy
doesn't look too special.
283
00:15:23,356 --> 00:15:25,256
So, this here
is a very nice image
284
00:15:25,258 --> 00:15:27,825
Taken with the hubble
space telescope.
285
00:15:27,827 --> 00:15:29,127
That's the galactic center,
286
00:15:29,129 --> 00:15:32,330
Where the supermassive black
hole should reside.
287
00:15:32,332 --> 00:15:34,332
And then these are
the spiral arms,
288
00:15:34,334 --> 00:15:36,434
Where lots of stars
are being formed.
289
00:15:37,570 --> 00:15:39,203
Narrator: But look closer,
and there appears
290
00:15:39,205 --> 00:15:43,675
To be a mysterious dark patch
in one of the spiral arms.
291
00:15:43,677 --> 00:15:46,544
So we think that in
this darker area here,
292
00:15:48,014 --> 00:15:51,482
There's no dust and there's no
gas able to create the stars.
293
00:15:51,484 --> 00:15:54,485
And that's why no
stars are being formed.
294
00:15:54,487 --> 00:15:58,323
So something must
have cleared the gas.
295
00:15:58,325 --> 00:16:00,491
Narrator: What strange forces
can clear out
296
00:16:00,493 --> 00:16:03,127
A huge patch of dust and stars?
297
00:16:04,331 --> 00:16:07,632
Mar looks at the galaxy
in radio waves.
298
00:16:07,634 --> 00:16:09,701
She sees something astonishing.
299
00:16:11,071 --> 00:16:12,770
A radio bright spot.
300
00:16:13,940 --> 00:16:16,474
Mezcua: What we are seeing here
is radio emission
301
00:16:16,476 --> 00:16:20,144
From a location
in the spiral arm of ngc 2276.
302
00:16:21,247 --> 00:16:22,947
The radio emission
that we detect
303
00:16:22,949 --> 00:16:26,584
Is located right here
in this dark region.
304
00:16:26,586 --> 00:16:32,490
Narrator:
Mar thinks this radio bright
spot can only be one thing.
305
00:16:32,492 --> 00:16:34,659
Blasting a hole in
the side of the galaxy
306
00:16:34,661 --> 00:16:36,694
Reveals the scale of the void.
307
00:16:38,164 --> 00:16:42,767
It's enormous and almost
completely devoid of stars.
308
00:16:42,769 --> 00:16:47,772
The reason lies within --
a jet of intense radiation.
309
00:16:47,774 --> 00:16:49,841
Like a galactic blowtorch,
310
00:16:49,843 --> 00:16:53,144
It's blasted away
the star-forming gas.
311
00:16:53,146 --> 00:16:55,780
Traveling six light years
along the jet
312
00:16:55,782 --> 00:16:57,782
Leads to the heart of the void
313
00:16:57,784 --> 00:17:00,818
And the ultimate source
of the radiation --
314
00:17:00,820 --> 00:17:05,757
A black hole gorging itself
on a vortex of cosmic dust.
315
00:17:05,759 --> 00:17:07,792
As it feeds, the black hole
316
00:17:07,794 --> 00:17:10,895
Whips the dust around it
into a frenzy,
317
00:17:10,897 --> 00:17:14,665
Blasting out scorching beams
of intense radiation.
318
00:17:14,667 --> 00:17:18,036
But could this just be
a small stellar black hole
319
00:17:18,038 --> 00:17:21,139
With a mass of a few times
that of our sun?
320
00:17:21,141 --> 00:17:23,074
It seems unlikely.
321
00:17:23,076 --> 00:17:24,842
Because of the size
of this dark region,
322
00:17:24,844 --> 00:17:27,545
We know that it cannot
be a stellar black hole.
323
00:17:27,547 --> 00:17:29,414
It must be something bigger.
324
00:17:29,416 --> 00:17:32,383
Narrator: And if this were
a supermassive black hole
325
00:17:32,385 --> 00:17:36,120
Weighing a few million times
the mass of the sun,
326
00:17:36,122 --> 00:17:38,589
It would be at the center
of its galaxy,
327
00:17:38,591 --> 00:17:40,691
Not here on the outskirts.
328
00:17:40,693 --> 00:17:43,628
Could this be a seed black hole,
329
00:17:43,630 --> 00:17:46,030
The missing link
that can help tell us
330
00:17:46,032 --> 00:17:49,233
How supermassive black holes
and galaxies form?
331
00:18:02,849 --> 00:18:07,852
♪
332
00:18:07,854 --> 00:18:10,621
Narrator: At the medicina
observatory in northern Italy,
333
00:18:10,623 --> 00:18:14,292
Astrophysicist mar mezcua
could be on the verge
334
00:18:14,294 --> 00:18:15,760
Of a breakthrough discovery.
335
00:18:15,762 --> 00:18:19,497
Using radio telescopes,
she looks at galaxy ngc 2276
336
00:18:21,534 --> 00:18:24,168
And sees something remarkable,
337
00:18:24,170 --> 00:18:26,704
A bright spot of
intense radiation
338
00:18:26,706 --> 00:18:31,409
That could only be caused
by one thing: A black hole.
339
00:18:31,411 --> 00:18:33,978
Could it be a seed black hole?
340
00:18:33,980 --> 00:18:36,481
We have used radio observations
of this black hole,
341
00:18:36,483 --> 00:18:38,483
Together with x-ray
measurements,
342
00:18:38,485 --> 00:18:40,218
To estimate the black hole mass.
343
00:18:40,220 --> 00:18:42,854
And we find that this
black hole has a mass
344
00:18:42,856 --> 00:18:46,691
Of more than 10,000 times
the mass of the sun.
345
00:18:46,693 --> 00:18:48,326
Narrator: That puts
this black hole
346
00:18:48,328 --> 00:18:50,862
Firmly in the
middleweight division.
347
00:18:50,864 --> 00:18:54,732
It looks like this really
is a seed black hole.
348
00:18:57,670 --> 00:18:59,070
This is a source that warrants
349
00:18:59,072 --> 00:19:01,005
Really urgent
observational follow-up.
350
00:19:01,007 --> 00:19:04,142
Because it very well may
be a seed black hole.
351
00:19:04,144 --> 00:19:05,576
And this is really cool,
352
00:19:05,578 --> 00:19:09,680
Because we don't have really
firm evidence of these things.
353
00:19:09,682 --> 00:19:11,215
Narrator: If mar is right,
354
00:19:11,217 --> 00:19:14,152
Seed black holes
really do exist.
355
00:19:14,154 --> 00:19:16,587
It's a huge breakthrough
in our understanding
356
00:19:16,589 --> 00:19:20,725
Of how supermassive black holes
and galaxies grow.
357
00:19:20,727 --> 00:19:23,494
But it's not
a confirmed find yet,
358
00:19:23,496 --> 00:19:27,198
And other scientists
are hot on her heels.
359
00:19:27,200 --> 00:19:29,901
At mcdonald observatory
in texas,
360
00:19:29,903 --> 00:19:31,836
Eva noyola is on the trail
361
00:19:31,838 --> 00:19:33,871
Of another
middleweight contender.
362
00:19:35,008 --> 00:19:37,008
Her potential seed black hole
363
00:19:37,010 --> 00:19:39,744
Sits right in
our galaxy's backyard.
364
00:19:39,746 --> 00:19:42,680
Eva investigates star clusters.
365
00:19:43,883 --> 00:19:46,150
Star clusters are these
collection of stars
366
00:19:46,152 --> 00:19:49,020
That are gravitating around
each other independently,
367
00:19:49,022 --> 00:19:50,821
And they tend to
orbit around galaxies.
368
00:19:50,823 --> 00:19:55,760
So they can go from 10,000 stars
only to millions of stars.
369
00:19:57,330 --> 00:20:01,399
Narrator: Around 200 large star
clusters orbit the milky way,
370
00:20:01,401 --> 00:20:05,670
And eva thinks inside them,
we may find seed black holes.
371
00:20:06,773 --> 00:20:10,241
Eva has found one cluster,
omega centauri,
372
00:20:10,243 --> 00:20:12,877
That behaves
particularly strangely.
373
00:20:13,846 --> 00:20:17,682
Omega centauri is the largest
star cluster around the galaxy.
374
00:20:17,684 --> 00:20:19,550
It's roughly a spherical shape,
375
00:20:19,552 --> 00:20:22,186
And it's about
two million stars.
376
00:20:22,188 --> 00:20:24,355
The density of stars is so high
377
00:20:24,357 --> 00:20:25,990
That compared to our
solar neighborhood,
378
00:20:25,992 --> 00:20:28,259
The stars are
a thousand times closer.
379
00:20:28,261 --> 00:20:30,094
That's where things
are harder to measure,
380
00:20:30,096 --> 00:20:31,963
Because there are so many
stars near to each other,
381
00:20:31,965 --> 00:20:34,065
But it's very hard
to tell them apart.
382
00:20:35,501 --> 00:20:37,635
Narrator: Eva thinks
that a monster lurks
383
00:20:37,637 --> 00:20:40,871
At the heart of this
dense cluster of stars.
384
00:20:40,873 --> 00:20:43,474
There's something creating
gravitational pull,
385
00:20:43,476 --> 00:20:45,376
But it's not visible.
386
00:20:45,378 --> 00:20:46,844
Right there in the middle.
[chuckles]
387
00:20:48,381 --> 00:20:50,248
Narrator: Eva carefully observes
388
00:20:50,250 --> 00:20:54,185
How the stars inside the cluster
move through space
389
00:20:54,187 --> 00:20:56,887
And finds something astonishing.
390
00:20:56,889 --> 00:20:59,890
Noyola:
The speed of the stars in
the very center of the cluster
391
00:20:59,892 --> 00:21:03,094
Is about four times faster than
the speed at the outskirts.
392
00:21:03,096 --> 00:21:04,662
So it's a pretty big increase.
393
00:21:05,732 --> 00:21:09,066
Narrator: Something small but
with a huge amount of gravity
394
00:21:09,068 --> 00:21:12,370
Seems to be whipping the stars
in the cluster's center
395
00:21:12,372 --> 00:21:13,971
Into a frenzy.
396
00:21:13,973 --> 00:21:16,374
But no matter how
hard eva looks,
397
00:21:16,376 --> 00:21:18,709
She can't see this object.
398
00:21:18,711 --> 00:21:21,112
Noyola: You have a very massive,
very compact object
399
00:21:21,114 --> 00:21:23,080
That does not give off light.
400
00:21:23,082 --> 00:21:27,118
This thing essentially
jumped at me.
401
00:21:27,120 --> 00:21:30,021
Narrator: If eva's right,
for billions of years,
402
00:21:30,023 --> 00:21:33,724
Omega centauri has been
hiding a dark secret.
403
00:21:34,827 --> 00:21:39,163
Deep inside, stars hurdle
through space on overdrive,
404
00:21:39,165 --> 00:21:41,999
Many times faster
than they should.
405
00:21:42,001 --> 00:21:44,769
Only a dense object
with immense gravity
406
00:21:44,771 --> 00:21:48,272
Can pull stars into orbits
like this --
407
00:21:48,274 --> 00:21:50,408
A black hole.
408
00:21:50,410 --> 00:21:54,945
And judging by the sheer speeds
of the stars in its grasp,
409
00:21:54,947 --> 00:21:58,382
This is no small
stellar black hole.
410
00:21:58,384 --> 00:22:01,285
It's a seed black hole.
411
00:22:01,287 --> 00:22:02,753
My heart rate just elevated
412
00:22:02,755 --> 00:22:04,522
Because it was so
exciting to see.
413
00:22:04,524 --> 00:22:07,358
It was very clear that
there was something very
interesting there.
414
00:22:07,360 --> 00:22:09,393
Narrator:
This seed isn't feeding,
415
00:22:09,395 --> 00:22:13,030
So it's not producing
radio waves.
416
00:22:13,032 --> 00:22:16,901
But by measuring the speeds of
the stars orbiting around it,
417
00:22:16,903 --> 00:22:20,037
Eva can still calculate
how big it is.
418
00:22:20,039 --> 00:22:22,740
Noyola: The size of the black
hole that is the best fit
419
00:22:22,742 --> 00:22:26,310
Is 50,000 times
the mass of the sun.
420
00:22:26,312 --> 00:22:29,313
It is right between the little
stellar-mass black holes,
421
00:22:29,315 --> 00:22:30,848
Which are a lot smaller,
422
00:22:30,850 --> 00:22:32,083
And the supermassive
black holes,
423
00:22:32,085 --> 00:22:33,918
Which are much, much bigger.
424
00:22:33,920 --> 00:22:34,919
The fact that it's in the middle
425
00:22:34,921 --> 00:22:37,355
Is what makes it
a seed black hole.
426
00:22:37,357 --> 00:22:41,125
Narrator: Weighing in at 50,000
times the mass of the sun,
427
00:22:41,127 --> 00:22:42,893
This is five times heavier
428
00:22:42,895 --> 00:22:45,162
Than mar mezcua's black hole
429
00:22:45,164 --> 00:22:49,433
But still firmly within the seed
black hole weight division.
430
00:22:49,435 --> 00:22:52,636
But what makes eva's seed
even more intriguing
431
00:22:52,638 --> 00:22:55,473
Is the cluster of stars
that hang around it
432
00:22:55,475 --> 00:22:57,208
Like moths around a flame.
433
00:22:58,978 --> 00:23:02,613
Could this entourage of stars
be a clue to how galaxies
434
00:23:02,615 --> 00:23:06,317
Like the milky way first
formed in the early universe?
435
00:23:06,319 --> 00:23:10,221
And can this strange glow
from the galactic center
436
00:23:10,223 --> 00:23:13,591
Reveal that our own
supermassive black hole
437
00:23:13,593 --> 00:23:17,328
Is still growing fat
on a diet of these seeds?
438
00:23:17,330 --> 00:23:21,565
Oluseyi: These seed black holes
may exist in our galaxy today.
439
00:23:21,567 --> 00:23:24,435
Maybe they're in
our own cosmic backyard.
440
00:23:24,437 --> 00:23:32,042
♪
441
00:23:38,518 --> 00:23:44,755
♪
442
00:23:44,757 --> 00:23:48,025
Narrator: Astronomers are
on the verge of a breakthrough.
443
00:23:48,027 --> 00:23:50,027
They've found evidence
that middleweight
444
00:23:50,029 --> 00:23:53,931
Seed black holes
really do exist.
445
00:23:53,933 --> 00:23:56,400
And one seed black hole
in particular
446
00:23:56,402 --> 00:24:00,137
Has astronomers excited,
because clustered around it
447
00:24:00,139 --> 00:24:02,907
Is a bunch of stars,
like a mini galaxy.
448
00:24:04,744 --> 00:24:08,579
It hints at an astonishing
history for these middleweights.
449
00:24:08,581 --> 00:24:10,714
Seed black holes and
the stars they drag with them
450
00:24:10,716 --> 00:24:12,883
Could have helped build
451
00:24:12,885 --> 00:24:16,320
The vast collections of stars
we call galaxies.
452
00:24:19,559 --> 00:24:21,892
A clue to their
galaxy-building role
453
00:24:21,894 --> 00:24:25,095
Lies inside the central
bulge of the milky way.
454
00:24:26,265 --> 00:24:28,032
The stars inside the bulge
455
00:24:28,034 --> 00:24:30,568
Resemble those
in the star clusters
456
00:24:30,570 --> 00:24:33,471
Thought to be home
to seed black holes.
457
00:24:33,473 --> 00:24:35,473
Noyola: The population
at the center of galaxies
458
00:24:35,475 --> 00:24:37,741
In galactic bulges
really matches
459
00:24:37,743 --> 00:24:40,778
Very well the population
of the star clusters.
460
00:24:40,780 --> 00:24:44,014
So we know that a lot of the
bulge is made of those stars.
461
00:24:45,017 --> 00:24:46,450
Narrator:
If the centers of galaxies
462
00:24:46,452 --> 00:24:49,119
Are largely built
from these star clusters,
463
00:24:49,121 --> 00:24:53,357
This suggests an extraordinary
role for seed black holes.
464
00:24:54,861 --> 00:24:56,460
13 billion years ago,
465
00:24:56,462 --> 00:24:59,430
The universe didn't have
large spiral galaxies
466
00:24:59,432 --> 00:25:00,764
Like the milky way.
467
00:25:00,766 --> 00:25:04,869
Instead, it may have been
filled with seed black holes,
468
00:25:04,871 --> 00:25:07,938
Each with a disorganized
mass of stars around it.
469
00:25:09,442 --> 00:25:13,744
It's from these ingredients that
scientists think galaxies grew.
470
00:25:15,014 --> 00:25:17,381
Seed black holes
could act as anchors
471
00:25:17,383 --> 00:25:19,950
For the stars that
swarm around them,
472
00:25:19,952 --> 00:25:23,487
And those anchors could find
one another in the void of space
473
00:25:23,489 --> 00:25:25,689
And coalesce to form
a larger galaxy.
474
00:25:27,793 --> 00:25:30,227
Narrator: With seed black holes
as the catalyst,
475
00:25:30,229 --> 00:25:32,830
We can imagine how
the milky way formed.
476
00:25:35,101 --> 00:25:37,434
Two star clusters collide.
477
00:25:37,436 --> 00:25:42,706
Their stars are pulled out
of orbit and chaotically mix.
478
00:25:42,708 --> 00:25:47,044
In the thick of the action,
two seed black holes face off,
479
00:25:47,046 --> 00:25:50,180
Circling each other
in a deadly dance.
480
00:25:52,552 --> 00:25:58,155
They finally fuse to
form a bigger black hole.
481
00:25:58,157 --> 00:26:00,958
The increased gravity
sucks in more material
482
00:26:00,960 --> 00:26:03,494
And pulls more star
clusters into the fray,
483
00:26:03,496 --> 00:26:06,697
Until eventually the seeds
had ballooned...
484
00:26:09,602 --> 00:26:11,802
...Into a supermassive
black hole.
485
00:26:13,673 --> 00:26:17,174
And around this monster,
the stars from those clusters
486
00:26:17,176 --> 00:26:20,177
Helped to form our galaxy,
the milky way.
487
00:26:24,317 --> 00:26:26,684
I find it amazing that
these little star clusters
488
00:26:26,686 --> 00:26:28,786
That are old and tiny
489
00:26:28,788 --> 00:26:31,522
End up being these fantastic
archeological objects
490
00:26:31,524 --> 00:26:33,290
That end up being
the building blocks
491
00:26:33,292 --> 00:26:36,393
Of the galaxies that we observe
everywhere in the universe.
492
00:26:36,395 --> 00:26:38,529
Narrator: The theory
that seed black holes
493
00:26:38,531 --> 00:26:41,465
Helped build the milky way
is an exciting one.
494
00:26:41,467 --> 00:26:44,768
But where's the proof?
495
00:26:44,770 --> 00:26:47,738
Scientists scour
the hearts of galaxies
496
00:26:47,740 --> 00:26:50,341
For evidence
of seed black holes.
497
00:26:50,343 --> 00:26:54,478
The holy grail is now to find
stray seed black holes
498
00:26:54,480 --> 00:26:57,081
That are still
in the process of merging.
499
00:27:00,152 --> 00:27:04,021
In southern arizona sits
a unique set of telescopes.
500
00:27:05,958 --> 00:27:07,124
This is veritas.
501
00:27:10,696 --> 00:27:13,297
Veritas is made up
of four dishes,
502
00:27:13,299 --> 00:27:18,102
Each 40 feet across with
350 hexagonal mirrors apiece.
503
00:27:20,006 --> 00:27:21,905
These bizarre-looking
instruments
504
00:27:21,907 --> 00:27:24,074
Are designed to look
for a special form
505
00:27:24,076 --> 00:27:27,244
Of intense, high-energy light
called gamma rays.
506
00:27:29,448 --> 00:27:32,750
John quinn believes
gamma ray telescopes like these
507
00:27:32,752 --> 00:27:36,787
Could offer up a brand-new way
to hunt for seed black holes.
508
00:27:39,625 --> 00:27:43,293
Veritas is a ground-based
gamma ray observatory.
509
00:27:43,295 --> 00:27:46,363
It lets us study sources
of what are known
510
00:27:46,365 --> 00:27:48,232
As very high-energy gamma rays,
511
00:27:48,234 --> 00:27:51,535
Gamma rays a million-million
times more energetic than light,
512
00:27:51,537 --> 00:27:53,604
Way higher than anything
we can produce
513
00:27:53,606 --> 00:27:56,106
In any laboratory on earth.
514
00:27:56,108 --> 00:27:57,541
It leaves a very sharp image
515
00:27:57,543 --> 00:27:58,876
Of the gamma rays
when they come in.
516
00:28:01,180 --> 00:28:03,981
Narrator: Gamma rays
are light waves on steroids
517
00:28:03,983 --> 00:28:10,354
Created by the most extreme
objects in the cosmos --
518
00:28:10,356 --> 00:28:12,656
Violently spinning pulsars...
519
00:28:14,193 --> 00:28:16,093
...Exploding supernovae...
520
00:28:20,032 --> 00:28:23,834
...And enormous quasars...
521
00:28:23,836 --> 00:28:25,069
All fire out gamma rays.
522
00:28:27,506 --> 00:28:29,940
And when these high-energy
waves hit earth,
523
00:28:31,544 --> 00:28:33,510
They tear through
the atmosphere,
524
00:28:33,512 --> 00:28:35,713
Creating bursts of blue light.
525
00:28:37,416 --> 00:28:40,250
These bursts are
normally invisible,
526
00:28:40,252 --> 00:28:42,286
But veritas can see them.
527
00:28:45,224 --> 00:28:47,257
Here, we're seeing
various events.
528
00:28:48,661 --> 00:28:52,763
Each change you see
is 2,000 millionths of a second.
529
00:28:52,765 --> 00:28:54,665
We have to use
specialized detectors,
530
00:28:54,667 --> 00:28:57,801
High-speed electronics
to detect these.
531
00:28:57,803 --> 00:28:59,236
Narrator:
And gamma ray astronomy
532
00:28:59,238 --> 00:29:03,707
Has thrown scientists
a stunning curve ball,
533
00:29:03,709 --> 00:29:05,642
One that could provide the proof
534
00:29:05,644 --> 00:29:09,747
That seed black holes
helped build the galaxy.
535
00:29:09,749 --> 00:29:13,283
Investigators discovered
that the center of our galaxy
536
00:29:13,285 --> 00:29:16,220
Emits an unexplained
gamma ray glow.
537
00:29:17,857 --> 00:29:20,858
This is the entire
gamma ray sky.
538
00:29:20,860 --> 00:29:23,627
The plane of the galaxy
is along the center,
539
00:29:23,629 --> 00:29:26,697
And we can see the center
of the galaxy here.
540
00:29:26,699 --> 00:29:28,766
Narrator:
This central region fires out
541
00:29:28,768 --> 00:29:30,934
Many more gamma rays
than it should.
542
00:29:33,806 --> 00:29:36,807
And we currently don't
understand what is causing this.
543
00:29:37,910 --> 00:29:40,744
Plait:
Gamma rays are a form of light
that's pretty hard to produce.
544
00:29:40,746 --> 00:29:43,747
You need to have a huge
energetic source to make them.
545
00:29:43,749 --> 00:29:45,716
So we expected
to see some coming
546
00:29:45,718 --> 00:29:46,917
From the center of the galaxy.
547
00:29:46,919 --> 00:29:49,286
That's a lot of activity
going on there.
548
00:29:49,288 --> 00:29:52,222
The problem is we're
seeing too many.
549
00:29:52,224 --> 00:29:54,458
Our milky way is overproducing.
550
00:29:54,460 --> 00:29:57,461
There's an excess of gamma rays
coming from there.
551
00:29:57,463 --> 00:29:58,328
Why?
552
00:30:01,033 --> 00:30:03,100
Narrator: Could thousands
of seed black holes
553
00:30:03,102 --> 00:30:05,102
Orbit the supermassive
black hole
554
00:30:05,104 --> 00:30:06,770
At the heart of the milky way,
555
00:30:06,772 --> 00:30:10,007
Emitting gamma rays as they
circle the galactic center?
556
00:30:11,243 --> 00:30:14,678
Quinn: It is possible that
some of the gamma ray events
557
00:30:14,680 --> 00:30:18,549
That we're seeing are produced
from seed black holes
558
00:30:18,551 --> 00:30:20,484
In the vicinity of
the galactic center.
559
00:30:21,587 --> 00:30:24,421
Narrator: But how can
black holes produce radiation
560
00:30:24,423 --> 00:30:27,558
If nothing ever escapes
their gravitational pull,
561
00:30:27,560 --> 00:30:29,927
Not even light?
562
00:30:29,929 --> 00:30:34,298
The answer could lie in the
cosmic debris that they feed on.
563
00:30:34,300 --> 00:30:37,134
Matter is attracted
towards the seed black hole
564
00:30:37,136 --> 00:30:38,969
By its enormous gravity,
565
00:30:38,971 --> 00:30:40,838
And as the black hole spins,
566
00:30:40,840 --> 00:30:43,740
Its gravity whips the matter
into a frenzy,
567
00:30:43,742 --> 00:30:46,143
Generating huge
amounts of energy,
568
00:30:46,145 --> 00:30:49,746
Which blasts out from the area
around the black hole
569
00:30:49,748 --> 00:30:51,982
In a bright beacon of radiation
570
00:30:51,984 --> 00:30:54,685
And perhaps even gamma rays.
571
00:30:54,687 --> 00:30:58,455
Could this be the explanation
for the mysterious glow
572
00:30:58,457 --> 00:31:01,491
Coming from the heart
of the milky way?
573
00:31:01,493 --> 00:31:04,061
Could it be seed black holes?
574
00:31:04,063 --> 00:31:06,830
Gamma rays could be
the observable beacons
575
00:31:06,832 --> 00:31:09,066
For otherwise unobservable
seed black holes.
576
00:31:09,068 --> 00:31:12,536
And that would be an absolutely
transformational discovery.
577
00:31:12,538 --> 00:31:17,741
♪
578
00:31:24,350 --> 00:31:29,253
♪
579
00:31:29,255 --> 00:31:32,055
Narrator: If the mysteriously
glowing galactic center
580
00:31:32,057 --> 00:31:36,393
At the heart of our milky way
is thanks to seed black holes,
581
00:31:36,395 --> 00:31:39,029
It would be an
astonishing discovery.
582
00:31:39,031 --> 00:31:40,097
It would tell us
583
00:31:40,099 --> 00:31:43,233
Our supermassive black
hole isn't alone.
584
00:31:43,235 --> 00:31:46,169
There could be seed
black holes orbiting it --
585
00:31:46,171 --> 00:31:48,238
Seeds that,
billions of years ago,
586
00:31:48,240 --> 00:31:51,541
Delivered the stars that
helped build the milky way.
587
00:31:51,543 --> 00:31:53,911
That would really
help fill in the story
588
00:31:53,913 --> 00:31:56,847
Fill in the puzzle of how
structure in the universe forms.
589
00:31:58,150 --> 00:31:59,716
Narrator: It would be
the final proof
590
00:31:59,718 --> 00:32:03,487
That seed black holes
helped build our galaxy.
591
00:32:03,489 --> 00:32:05,856
We may even be lucky enough
to find that
592
00:32:05,858 --> 00:32:11,261
Our supermassive black hole is
still merging with these seeds.
593
00:32:11,263 --> 00:32:15,132
There could be see black holes
still in our galaxy today.
594
00:32:15,134 --> 00:32:19,469
Our supermassive black hole
may still be feeding on them.
595
00:32:19,471 --> 00:32:21,538
Narrator:
And with each collision,
596
00:32:21,540 --> 00:32:25,275
Our supermassive black hole
becomes even more massive.
597
00:32:25,277 --> 00:32:33,583
♪
598
00:32:33,585 --> 00:32:35,953
Seed black holes
could turn out to be
599
00:32:35,955 --> 00:32:39,356
The most important
objects in the universe --
600
00:32:39,358 --> 00:32:41,191
A cosmic game changer.
601
00:32:43,796 --> 00:32:46,797
But one mystery
remains unsolved.
602
00:32:48,434 --> 00:32:51,301
If these seed black holes
are so important
603
00:32:51,303 --> 00:32:53,971
To the story of our universe,
604
00:32:53,973 --> 00:32:55,772
Where did they come from?
605
00:32:59,611 --> 00:33:04,014
In austin, texas, volker bromm
knows how difficult it is
606
00:33:04,016 --> 00:33:05,615
To make seed black holes.
607
00:33:06,685 --> 00:33:11,321
That's because volker tries to
make his own seed black holes
608
00:33:11,323 --> 00:33:14,825
Inside this vast
supercomputer, stampede.
609
00:33:16,095 --> 00:33:18,662
What we see here
is one of the most powerful
610
00:33:18,664 --> 00:33:21,264
Supercomputers on planet earth.
611
00:33:21,266 --> 00:33:25,035
Supercomputers like this
allow us to basically take
612
00:33:25,037 --> 00:33:28,305
The laws of nature and create
a sophisticated computer code
613
00:33:28,307 --> 00:33:31,708
And then let the computer
advance the universe
614
00:33:31,710 --> 00:33:34,978
Over billions of years in time.
615
00:33:34,980 --> 00:33:38,015
Narrator: In short,
volker is creating a simulation
616
00:33:38,017 --> 00:33:41,651
Of the early universe
inside a computer.
617
00:33:41,653 --> 00:33:43,153
He wants to investigate
618
00:33:43,155 --> 00:33:47,691
How nature could've cooked up
these crucial seed black holes.
619
00:33:47,693 --> 00:33:49,860
A few million years
after the big bang,
620
00:33:49,862 --> 00:33:52,329
We had a very boring universe.
621
00:33:52,331 --> 00:33:54,698
What cosmologists
call the dark ages.
622
00:33:56,101 --> 00:33:59,503
In the dark ages, there were
no sources of light --
623
00:33:59,505 --> 00:34:02,839
No stars, no galaxies,
no black holes.
624
00:34:02,841 --> 00:34:07,244
Narrator: The early universe
contained simple clouds of gas.
625
00:34:07,246 --> 00:34:10,614
Volker suspects these
giant clouds collapsed
626
00:34:10,616 --> 00:34:15,352
To form the biggest stars
the universe has ever seen,
627
00:34:15,354 --> 00:34:20,257
Perhaps hundreds of thousands of
times more massive than our sun.
628
00:34:20,259 --> 00:34:23,193
These supergiant stars
quickly collapsed
629
00:34:23,195 --> 00:34:26,730
To form seed black holes,
630
00:34:26,732 --> 00:34:28,899
But volker's early simulations
631
00:34:28,901 --> 00:34:30,767
Reveal a problem
with the theory.
632
00:34:30,769 --> 00:34:33,603
His virtual stars always explode
633
00:34:33,605 --> 00:34:36,473
Before they grow big enough
to form a seed black hole.
634
00:34:40,612 --> 00:34:43,980
So here we see a massive
star dying, exploding,
635
00:34:43,982 --> 00:34:47,384
Putting in a bubble
of high-energy radiation.
636
00:34:48,787 --> 00:34:51,455
This energy input basically
drives the gas out again.
637
00:34:52,791 --> 00:34:55,992
And this limits the ability
of the gas to collapse
638
00:34:55,994 --> 00:34:59,262
And eventually to end up
in a black hole.
639
00:34:59,264 --> 00:35:02,966
Narrator:
The virtual stars run out
of fuel too quickly and explode.
640
00:35:04,803 --> 00:35:07,237
Bromm: Stars are
producers of energy.
641
00:35:07,239 --> 00:35:09,005
They eventually explode,
642
00:35:09,007 --> 00:35:12,742
And they create
outward-acting pressure.
643
00:35:12,744 --> 00:35:17,080
Narrator:
The explosions stop the gas
cloud collapsing further,
644
00:35:17,082 --> 00:35:19,950
And although the dying stars
in the simulation
645
00:35:19,952 --> 00:35:21,852
Do form black holes,
646
00:35:21,854 --> 00:35:24,321
They're much smaller
than the seed black holes
647
00:35:24,323 --> 00:35:26,857
That helped build
the galaxies we see today.
648
00:35:28,494 --> 00:35:30,360
Volker needs a new recipe,
649
00:35:30,362 --> 00:35:32,896
One that'll make an enormous
cloud of gas
650
00:35:32,898 --> 00:35:35,599
Collapse to form
a single massive star,
651
00:35:35,601 --> 00:35:37,634
Not thousands of smaller ones.
652
00:35:40,205 --> 00:35:41,872
It's possible that
in the early universe
653
00:35:41,874 --> 00:35:44,841
Conditions were very different.
654
00:35:44,843 --> 00:35:48,044
Instead of clouds forming
beautiful little star clusters,
655
00:35:48,046 --> 00:35:53,250
Giant clouds of dust and gas
all collapsed at once.
656
00:35:53,252 --> 00:35:55,952
If conditions are just right,
that gas can collapse
657
00:35:55,954 --> 00:35:58,722
All the way down
into a very massive seed.
658
00:35:58,724 --> 00:36:01,324
Narrator: But what are
these conditions?
659
00:36:01,326 --> 00:36:04,861
Volker realizes that
there is a magic ingredient
660
00:36:04,863 --> 00:36:07,764
That could allow seed
black holes to form.
661
00:36:07,766 --> 00:36:13,770
♪
662
00:36:20,245 --> 00:36:26,316
♪
663
00:36:26,318 --> 00:36:29,719
Narrator: Cosmologists believe
the galaxies we see today
664
00:36:29,721 --> 00:36:32,556
And the supermassive black
holes at their hearts
665
00:36:32,558 --> 00:36:34,791
Were formed
in the early universe
666
00:36:34,793 --> 00:36:38,094
By middleweight seed
black holes merging together,
667
00:36:38,096 --> 00:36:40,997
But how did these
seed black holes form?
668
00:36:40,999 --> 00:36:43,500
It might come down
to one ingredient.
669
00:36:43,502 --> 00:36:46,636
The mysterious substance --
dark matter.
670
00:36:46,638 --> 00:36:49,239
We now understand that
galaxies are really dominated
671
00:36:49,241 --> 00:36:51,274
By a form of matter
we can't see.
672
00:36:51,276 --> 00:36:52,876
We know it's there
by its gravity,
673
00:36:52,878 --> 00:36:54,544
But there's no other
signal from it at all.
674
00:36:54,546 --> 00:36:56,079
It's what we call dark matter.
675
00:36:58,350 --> 00:37:01,151
Narrator: Dark matter,
despite being invisible,
676
00:37:01,153 --> 00:37:04,654
Could allow seed
black holes to form
677
00:37:04,656 --> 00:37:07,257
Because one thing we do know
about dark matter
678
00:37:07,259 --> 00:37:09,659
Is that it has
a gravitational pull.
679
00:37:09,661 --> 00:37:10,994
The really interesting spots
680
00:37:10,996 --> 00:37:14,397
Are where we have
these bright patches.
681
00:37:14,399 --> 00:37:17,167
This is where dark
matter has assembled,
682
00:37:17,169 --> 00:37:19,936
And the dark matter
then provides gravity.
683
00:37:19,938 --> 00:37:24,140
And this gravity is able to
attract gas that is quite hot.
684
00:37:26,745 --> 00:37:28,845
Narrator:
Volker runs new simulations.
685
00:37:29,948 --> 00:37:31,581
He fine tunes the conditions
686
00:37:31,583 --> 00:37:35,285
To produce a new
virtual universe,
687
00:37:35,287 --> 00:37:38,521
And inside this universe,
the pull of dark matter
688
00:37:38,523 --> 00:37:42,325
Overcomes the energy that had
previously prevented collapse.
689
00:37:43,395 --> 00:37:45,562
Here we see primordial gas
690
00:37:45,564 --> 00:37:50,867
Falling into the center
of the dark matter structure,
691
00:37:50,869 --> 00:37:52,869
And the gravity
of the dark matter is so strong
692
00:37:52,871 --> 00:37:55,739
That it can overcome
all opposing forces.
693
00:37:57,809 --> 00:38:00,343
Narrator: As more and more gas
rushes in,
694
00:38:00,345 --> 00:38:05,982
Volker's simulation produces
a huge spinning cosmic tornado.
695
00:38:05,984 --> 00:38:09,019
And this motion allows
the gas to be funneled,
696
00:38:09,021 --> 00:38:11,621
To be concentrated
in the center.
697
00:38:11,623 --> 00:38:14,324
Narrator: And over time,
the tornado grows.
698
00:38:15,894 --> 00:38:17,827
We start with 10 times
the mass of the sun.
699
00:38:17,829 --> 00:38:20,597
Eventually it goes to 100 times,
a 1,000 times,
700
00:38:20,599 --> 00:38:23,333
100,000 times
the mass of the sun.
701
00:38:24,670 --> 00:38:26,269
It was not clear that
this would be possible
702
00:38:26,271 --> 00:38:29,839
And we was rather,
in awe if you like.
703
00:38:29,841 --> 00:38:31,107
In a way, it's so beautiful
704
00:38:31,109 --> 00:38:33,810
That you almost are tempted
to fall in love with it.
705
00:38:33,812 --> 00:38:37,213
Narrator: When so much gas
funnels into one point in space,
706
00:38:37,215 --> 00:38:41,084
You can create a star like
nothing we've ever seen before.
707
00:38:42,421 --> 00:38:45,322
If the simulation is right,
in the early universe
708
00:38:45,324 --> 00:38:50,493
Dark matter filaments draw
cosmic gas into colossal clouds
709
00:38:50,495 --> 00:38:52,962
Bigger than a galaxy.
710
00:38:52,964 --> 00:38:56,232
Inside the clouds,
the temperature's rocket
711
00:38:56,234 --> 00:38:59,369
Until conditions are so extreme
712
00:38:59,371 --> 00:39:02,172
That in the center,
colossal blue stars
713
00:39:02,174 --> 00:39:05,875
Maybe 100,000 times
bigger than the sun
714
00:39:05,877 --> 00:39:08,345
Burst into life.
715
00:39:08,347 --> 00:39:11,548
But they consume fuel
at hellish speeds,
716
00:39:11,550 --> 00:39:13,817
And their cores
begin to collapse.
717
00:39:15,053 --> 00:39:17,053
A colossal quantity of material
718
00:39:17,055 --> 00:39:21,858
Crushes down
to a point in space...
719
00:39:21,860 --> 00:39:25,395
Creating an enormous
seed black hole.
720
00:39:26,965 --> 00:39:31,034
If we have a lot of gas that's
in the right configuration
721
00:39:31,036 --> 00:39:34,371
Allowing it to all fall
together in just the right way
722
00:39:34,373 --> 00:39:37,474
That it gets small enough,
then it would turn into
723
00:39:37,476 --> 00:39:40,443
A black hole of absolutely
any size that you want.
724
00:39:40,445 --> 00:39:43,179
So the black hole is instead
of being born an infant
725
00:39:43,181 --> 00:39:45,081
It's like being born
an adolescent.
726
00:39:45,083 --> 00:39:47,117
It's already very massive.
727
00:39:47,119 --> 00:39:51,421
This can put into place
a black hole in one go
728
00:39:51,423 --> 00:39:54,391
Already with a mass
of about a 100,000 times
729
00:39:54,393 --> 00:39:56,159
The mass of the sun,
maybe up to a million.
730
00:39:57,295 --> 00:40:00,830
Those conditions were
really very rare.
731
00:40:00,832 --> 00:40:05,135
And they only happened in
select regions in the universe.
732
00:40:05,137 --> 00:40:09,139
And it's almost, you could say,
a kind of cosmic miracle.
733
00:40:09,141 --> 00:40:10,607
Narrator: If volker's right,
734
00:40:10,609 --> 00:40:12,976
The seed black holes
we find today
735
00:40:12,978 --> 00:40:16,179
Are almost as old
as the universe itself --
736
00:40:16,181 --> 00:40:20,817
The last remaining survivors
of an ancient breed of objects.
737
00:40:23,855 --> 00:40:26,489
Tremblay: They could be relics
of a very, very, very,
738
00:40:26,491 --> 00:40:29,159
Narrow window of time
in the very early universe,
739
00:40:29,161 --> 00:40:31,327
Which means they would
be very old, right?
740
00:40:31,329 --> 00:40:32,762
Way older than we think.
741
00:40:33,932 --> 00:40:35,799
Narrator: And their
brothers and sisters merge
742
00:40:35,801 --> 00:40:40,303
To help build the supermassive
black holes we see today,
743
00:40:40,305 --> 00:40:43,473
Helping create
the galaxy we call home
744
00:40:43,475 --> 00:40:47,477
And bringing structure
to the universe.
745
00:40:47,479 --> 00:40:50,814
With this formation theory
for seed black holes,
746
00:40:50,816 --> 00:40:53,183
The story is complete.
747
00:40:54,719 --> 00:40:58,254
The huge seed black holes
that form from the gas clouds
748
00:40:58,256 --> 00:41:02,025
In the early universe
gather stars around them.
749
00:41:02,027 --> 00:41:05,428
These giant seeds merge and feed
750
00:41:05,430 --> 00:41:09,165
To grow into the monstrous
supermassive black holes
751
00:41:09,167 --> 00:41:12,268
That hold billions
of stars in orbit,
752
00:41:12,270 --> 00:41:15,138
Ultimately giving us
giant galaxies
753
00:41:15,140 --> 00:41:17,307
Like our home, the milky way.
754
00:41:19,311 --> 00:41:22,212
In a way, the only reason
you're sitting here right now
755
00:41:22,214 --> 00:41:24,614
Is that seed black holes,
a long time ago,
756
00:41:24,616 --> 00:41:26,015
Gathered the material
757
00:41:26,017 --> 00:41:28,418
To make galaxy
and star formation possible.
758
00:41:28,420 --> 00:41:31,321
Narrator: We may not have
a confirmed seed yet,
759
00:41:31,323 --> 00:41:33,490
But scientists are close.
760
00:41:33,492 --> 00:41:37,227
There's gonna come a time when
we have sort of the smoking gun.
761
00:41:37,229 --> 00:41:39,863
And it's like, "here it is.
Here is a seed black hole."
762
00:41:39,865 --> 00:41:42,499
And when we do that,
that's fantastic,
763
00:41:42,501 --> 00:41:44,000
Because that is a puzzle piece
764
00:41:44,002 --> 00:41:47,604
That goes into the jigsaw puzzle
of the universe
765
00:41:47,606 --> 00:41:49,639
And makes a more
complete picture
766
00:41:49,641 --> 00:41:51,407
Of what we know is out there.
767
00:41:51,409 --> 00:41:52,575
That's pretty exciting.
768
00:41:55,113 --> 00:41:56,446
Think about how much
a breakthrough
769
00:41:56,448 --> 00:41:57,780
That moment will be.
770
00:41:57,782 --> 00:41:59,549
We have based our entire idea
771
00:41:59,551 --> 00:42:01,951
About how galaxies form,
how stars form,
772
00:42:01,953 --> 00:42:04,921
Eventually how planets and you
and I form on the idea that
773
00:42:04,923 --> 00:42:07,824
Seed black holes were there
in the distant past,
774
00:42:07,826 --> 00:42:10,527
Beginning to grow
galaxies themselves.
775
00:42:10,529 --> 00:42:13,396
I think it's some of the most
exciting times right now
776
00:42:13,398 --> 00:42:15,198
In black hole astrophysics,
777
00:42:15,200 --> 00:42:17,567
And we just can't wait
to see what's next.
778
00:42:17,569 --> 00:42:21,337
Narrator:
And once we know for sure
seed black holes are out there,
779
00:42:21,339 --> 00:42:23,139
We'll have the final chapter
780
00:42:23,141 --> 00:42:26,409
In the story of how
the universe we see today
781
00:42:26,411 --> 00:42:27,677
Came to be.