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ROWE: Supermassive black holes,
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the engines that power
our universe.
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Supermassive black holes are
one of the major players
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in the evolution of galaxies.
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THALLER: With no supermassive
black holes,
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you have no Milky Way Galaxy,
no sun, no Earth, no you.
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ROWE: They're the driving force
at the heart
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of nearly every galaxy
in the cosmos.
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They are the most monstrous and
scary and bizarre aspects of
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our world,
which just fascinates me.
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ROWE: Now, a new
mystery has emerged
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about the oldest supermassive
black holes.
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TREMBLAY: We see supermassive
black holes in
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the very early universe.
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And we don't understand how
they grew so large so quickly.
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ROWE: We have clues about
their formation.
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But can we solve the mystery
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of this supermassive
growth spurt?
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[electricity buzzing]
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♪♪
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ROWE: 2017.
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Scientists gazing deep into
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the distant universe
discover something
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completely unexpected --
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A vast supermassive black
hole dating
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from the earliest days
of the universe.
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MINGARELLI: This was 690 million
years after the Big Bang.
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The universe was about 5 or
6% of the age that it is now.
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Finding a supermassive black
hole in the early universe is
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like finding an NFL
defensive lineman playing
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in peewee football.
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Something that big shouldn't
exist that young.
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ROWE: The supermassive black
hole wasn't just super early.
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It was super big, 800 million
times the mass of our sun.
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HOPKINS: In just a few hundred
million years,
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the universe has somehow been
able to collapse nearly
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a billion suns' worth of
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material into
a giant black hole.
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And we honestly just don't
know how that's possible.
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ROWE: We measure black holes
by the mass of our sun --
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Solar masses.
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Regular, or stellar,
black holes are a few
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to a hundred solar masses.
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Supermassive black holes weigh
from 100,000 to billions
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of suns.
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And scientists have now found
over 100 of these monsters in
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the early universe.
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We were shocked to find even one
of them existing so early
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after the Big Bang.
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It was kind of freakish,
to be honest,
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but then to find that there's
whole populations
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of these things that exist
and are well
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in place at the earliest times
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that we can look at
was truly shocking.
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ROWE: We believe
supermassive black holes might
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help explain the evolution
and the destiny of the universe.
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Astronomers are striving
to understand them.
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OLUSEYI:
Understanding the origin
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of supermassive black holes
and how
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they could form so early
in the universe's history is
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something that would change all
of astronomy and astrophysics.
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How do you get something
that massive to
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form in such a short amount
of time?
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It's a big question --
To begin to answer it,
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we have to start small,
by asking
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how regular stellar
black holes form.
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FILIPPENKO: Black holes form
through the collapse of stars.
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Everyone knows that --
You have a big enough star,
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and it'll collapse to
form a black hole.
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[explosion blasts]
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A really massive star dies in
a violent supernova explosion,
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and if they have sufficient
mass, what's left over
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collapses into a black hole.
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The bigger the star was,
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the bigger the black hole
is to start with.
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ROWE: Were the stars
of the early universe
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big enough to collapse into
supermassive black holes?
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The very early universe was
much different than
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the university you see
around us today.
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It was filled entirely with
hydrogen and helium gas.
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ROWE: This gas amassed
into giant clouds,
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which collapsed
under their own gravity.
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Nuclear fusion ignited
the dense cores,
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and the first stars were born.
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Now, we think that these
earliest clouds of gas probably
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made bigger stars than clouds
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of gas do in our local
or today's universe.
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It was possible to get huge,
giant stars that we call
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Population III stars that
were just utterly massive.
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ROWE: Population III stars are
the oldest category of star.
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Like stellar dinosaurs,
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they dominated the universe
a long time ago.
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Now, they're extinct.
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HOPKINS: They'd be weird stars.
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They would be incredibly
bright in the ultraviolet
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and have very unique signatures
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that are very different
from stars today,
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but precisely because they're
so big and so bright,
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they would be very short-lived.
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ROWE: These first stars
lived fast and died young...
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[explosion blasts]
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...exploding in supernovas,
leaving behind black holes.
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But were they supermassive
black holes?
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When a star blows up,
when it goes supernova,
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most of the mass
is ejected away.
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It just goes flying out,
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leaving a dense neutron star
or perhaps a black hole.
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But it won't have much
mass, because
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most of that mass was
blown away.
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Even though Population III
stars in the infant universe
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were very large,
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they weren't big enough to
leave a supermassive black hole
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behind when they exploded.
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Perhaps if we can skip
the supernova step,
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that might be one pathway to
understanding how supermassive
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black holes formed.
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Could a dying star's entire
mass collapse
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into a black hole?
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A clue may lie in a galaxy
nicknamed the Fireworks Galaxy.
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The Fireworks Galaxy has that
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flashy name,
because when you look at it,
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there are all these supernova
explosions going off
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and, um, making quite a show.
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ROWE: Recently, astronomers
were keeping an eye on
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one extremely bright star
in the Fireworks Galaxy.
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PLAIT: This star
is exactly the kind
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that we know explodes
as a supernova.
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Astronomers expected it
to explode,
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but then it did something
even weirder.
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Astronomy is so wonderful,
because sometimes you see things
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right in front of your eyes
that you can't explain.
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We saw an entire star
just disappear.
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ROWE: In 2007, the star
looked like this.
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By 2015, it had
completely vanished.
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There was no flare
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or debris
from a supernova explosion.
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So what the heck is going on?
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PLAIT: It turns out that not
every massive star blows up
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with all the fireworks
of a normal supernova.
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You can get what's called
a failed supernova.
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ROWE: A supernova fails
when the shockwave
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generated inside a collapsing
star can't escape.
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THALLER: In some cases,
when the star is very massive,
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the shockwave never has a chance
to get all the way out of
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the star by the time
the star itself
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collapses into a black hole,
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then you have
a failed supernova.
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ROWE: The Fireworks Galaxy star
may have been massive enough to
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smother its own explosion
before collapsing
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to form a black hole.
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THALLER: Everything collapses
into the black hole.
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You can actually
have a black hole
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with all the mass of
the original star.
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ROWE:
Back in the early universe,
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could the enormous
Population III stars have died
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as failed supernovas,
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leaving behind supermassive
black holes?
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These Population III stars
don't seem to me to be
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a good contender for
the precursor to supermassive
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black holes -- they just
would not have enough mass.
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FILIPPENKO: Even
the most massive stars are only
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a couple of hundred times
more massive than our sun,
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whereas a supermassive black
hole is millions or billions of
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times the mass of our sun.
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ROWE:
Early supermassive black holes
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can't have formed
from collapsing stars.
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Even giant stars aren't
massive enough.
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So is there some other path to
being supermassive?
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Were stellar black holes
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cosmic bodybuilders on
a fast-track bulking program?
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ROWE: How did
supermassive black holes in
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the early universe get
so large so quickly?
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We ruled out the idea
that they were
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created from the collapse of
very large stars.
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Maybe they started out
as smaller,
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stellar mass black holes
and grew to be supermassive
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by eating.
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TREMBLAY: Black holes
are not fussy eaters.
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They'll consume anything that
comes in their path.
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You know, gas, planets, stars.
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It doesn't matter,
and everything that they
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consume adds mass
to the black hole.
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ROWE: We've spotted
a stellar mass black hole
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currently eating
in our Milky Way Galaxy.
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15 times the mass of the sun,
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Cygnus X-1 is steadily feeding
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off the material
that swirls around it.
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MINGARELLI: Some black holes are
fed through things called
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accretion disks.
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It's kind of like the rings
around Saturn.
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There's this thick
or thin disk of
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material around the black hole
that feeds it.
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ROWE: Cygnus X-1's
secretion disc gets
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constant refills
from a nearby source,
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a vast star 20 times the mass
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of the sun called
a blue supergiant.
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The black hole has been
feeding on gas
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from this star for about
five million years.
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TREMBLAY: So if you ask, how do
black holes eat or consume gas?
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The answer is gravity, these are
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very massive objects, and
anything that comes within
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their sphere of influence can
be consumed by the black hole.
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ROWE: The more mass
a black hole gains, the greater
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its gravity and the more food
it attracts.
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PLAIT: A black hole growing
is a little bit
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like a snowball rolling
down a hill.
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The bigger the snowball gets,
the more snow it
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can accumulate,
and so the bigger it gets.
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It's a runaway effect.
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ROWE: But even if Cygnus X-1
follows this runaway
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growth trajectory,
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it still may never reach
supermassive status.
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The black holes of
the early universe must
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have fed at a much faster rate.
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The biggest issue
is how do you have
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enough time in the early
universe to go
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from a small black hole
that's born from a star to
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something that's supermassive?
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ROWE: GRS 1915 is another
stellar mass black hole.
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It's a greedy eater,
accreting at up to
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40 times the rate of Cygnus X-1,
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and when something gobbles
food that quickly,
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it can begin to overheat.
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MINGARELLI: The black hole is
accreting a lot of material,
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and as it's eating,
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the accretion disc
really heats up to very
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00:12:03,289 --> 00:12:04,422
high temperatures.
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00:12:04,523 --> 00:12:06,991
And at those high temperatures,
you can get
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a lot of light
coming out of the system.
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So the more material that
a black hole eats and swallows,
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the brighter it shines.
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ROWE: This stellar black hole
sometimes eats so much
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00:12:19,538 --> 00:12:21,773
so quickly, its accretion disk
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00:12:21,874 --> 00:12:25,376
pushes out radiation
almost a million times brighter
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00:12:25,478 --> 00:12:27,812
than our sun,
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00:12:27,913 --> 00:12:31,516
but this brightness has
a serious consequence.
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It stops the black hole from
eating and growing larger.
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If you wanted me to gain
as much mass as possible as
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00:12:39,358 --> 00:12:40,959
quickly as possible,
you would just keep
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feeding me hamburgers nonstop
or whatever, but...
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black holes have a problem
that when they eat a lot,
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they tend to just gobble up
a lot of the food in
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the neighborhood, and then also,
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00:12:53,405 --> 00:12:55,039
they start shining out
so much stuff
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00:12:55,141 --> 00:12:58,243
that it pushes away much
of the food.
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00:12:58,344 --> 00:13:00,779
ROWE:
The brightness, or luminosity,
247
00:13:00,880 --> 00:13:03,348
gets so intense, it pushes away
248
00:13:03,449 --> 00:13:04,482
incoming material,
249
00:13:04,583 --> 00:13:08,219
a sort of safety valve called
the Eddington Limit.
250
00:13:08,320 --> 00:13:11,055
So in many ways,
the Eddington rate could be
251
00:13:11,157 --> 00:13:13,892
a kind of a speed limit for
the growth of black holes.
252
00:13:13,993 --> 00:13:16,795
It could be a governor that
prevents black holes from
253
00:13:16,896 --> 00:13:18,229
growing even faster
254
00:13:18,330 --> 00:13:20,632
by just dumping more and more
gas onto it.
255
00:13:20,733 --> 00:13:23,434
Eventually, you're gonna hit
that Eddington limit,
256
00:13:23,536 --> 00:13:25,003
and that more gas
257
00:13:25,104 --> 00:13:27,705
that you're dumping on won't
actually reach the black hole.
258
00:13:28,974 --> 00:13:31,176
ROWE: This cosmic method
of portion control
259
00:13:31,277 --> 00:13:33,044
means that
stellar black holes in
260
00:13:33,145 --> 00:13:37,081
the early universe couldn't
have gained weight fast enough
261
00:13:37,183 --> 00:13:40,485
to become supermassive.
262
00:13:40,586 --> 00:13:42,787
SUTTER: Black holes
need time to grow.
263
00:13:42,888 --> 00:13:44,789
They need to feed.
They need to eat.
264
00:13:44,890 --> 00:13:47,025
Maybe you need
to skip a few steps.
265
00:13:47,126 --> 00:13:51,396
Maybe you need to start at
a medium size or bigger
266
00:13:51,497 --> 00:13:55,066
in order to get to supermassive
by the time we observe it.
267
00:13:56,435 --> 00:13:58,803
ROWE: So was there another
type of black hole
268
00:13:58,904 --> 00:14:00,104
in the early universe?
269
00:14:00,206 --> 00:14:03,575
Something big enough
to grow supermassive
270
00:14:03,676 --> 00:14:04,776
in the time available?
271
00:14:09,415 --> 00:14:12,283
ROWE: In 2017,
astronomers studied
272
00:14:12,384 --> 00:14:14,485
a dense star cluster called
273
00:14:14,587 --> 00:14:19,023
47 Tucanae on the outskirts
of our own galaxy.
274
00:14:20,559 --> 00:14:23,228
They detected 25 pulsars,
275
00:14:23,329 --> 00:14:25,930
bodies that spin
and emit radiation
276
00:14:26,031 --> 00:14:27,732
like cosmic lighthouses.
277
00:14:29,068 --> 00:14:33,805
SUTTER: These pulsars are all
orbiting a central object.
278
00:14:33,906 --> 00:14:36,507
And even though we couldn't
see the central object itself,
279
00:14:36,609 --> 00:14:41,012
we could watch the behavior in
the orbits of all these pulsars
280
00:14:41,080 --> 00:14:43,281
around it,
and we could figure out
281
00:14:43,382 --> 00:14:46,017
how big that central object was.
282
00:14:46,118 --> 00:14:47,452
Well, when you do the math,
283
00:14:47,553 --> 00:14:51,189
you come up with something
that is about 1,500 to 2,000
284
00:14:51,290 --> 00:14:53,524
times the mass of the sun
that's actually hidden in
285
00:14:53,626 --> 00:14:55,059
the heart of that
globular cluster.
286
00:14:55,160 --> 00:14:58,029
ROWE: So what is
the invisible object?
287
00:14:58,130 --> 00:15:03,167
Whatever's lurking at
the center of 47 Tucanae has
288
00:15:03,269 --> 00:15:06,704
to be big,
and it has to be black.
289
00:15:06,805 --> 00:15:09,807
ROWE: Astronomers think
it's a large black hole.
290
00:15:09,909 --> 00:15:12,110
At 1,500 times
291
00:15:12,211 --> 00:15:14,279
the mass of the sun, the object
292
00:15:14,380 --> 00:15:17,715
is much bigger than a regular
stellar black hole,
293
00:15:17,816 --> 00:15:21,152
but too small to
be supermassive.
294
00:15:21,253 --> 00:15:25,623
Could it be what's known as
an intermediate mass black hole?
295
00:15:25,724 --> 00:15:28,893
It's extremely hard to find any
296
00:15:28,994 --> 00:15:32,196
of these intermediate
mass black holes.
297
00:15:32,298 --> 00:15:34,666
ROWE: This rare category
of black hole
298
00:15:34,767 --> 00:15:38,870
ranges between 100
and 100,000 solar masses.
299
00:15:38,971 --> 00:15:41,205
At that size, they may have
300
00:15:41,307 --> 00:15:45,143
been large enough to become
supermassive very quickly.
301
00:15:45,244 --> 00:15:48,947
Intermediate mass black holes
could be what give
302
00:15:49,048 --> 00:15:52,684
supermassive black holes
a head start in life.
303
00:15:52,785 --> 00:15:54,819
ROWE: Astronomers
have never seen
304
00:15:54,920 --> 00:15:56,955
an intermediate mass black hole,
305
00:15:57,056 --> 00:16:01,192
but now, we've heard one,
calling to us
306
00:16:01,293 --> 00:16:02,860
from across the universe.
307
00:16:15,607 --> 00:16:19,610
ROWE: Astronomers search for
intermediate mass black holes.
308
00:16:19,712 --> 00:16:21,112
They may have been large enough
309
00:16:21,213 --> 00:16:24,115
to act as seeds
for the first supermassive
310
00:16:24,216 --> 00:16:25,817
black holes.
311
00:16:25,918 --> 00:16:28,820
Yet so far,
they've escaped discovery.
312
00:16:28,921 --> 00:16:30,855
They're like
the missing link. And I
313
00:16:30,956 --> 00:16:33,024
mean that for real.
They're missing.
314
00:16:33,125 --> 00:16:36,127
Imagine you're an alien who's
arrived on the planet Earth,
315
00:16:36,228 --> 00:16:39,097
and you know very little
about the human species,
316
00:16:39,198 --> 00:16:42,033
and when you look around,
you only notice tiny,
317
00:16:42,134 --> 00:16:44,402
tiny little children
and grown adults.
318
00:16:44,503 --> 00:16:47,171
You don't see any
adolescents, right?
319
00:16:47,272 --> 00:16:49,807
And intrinsically, you know
that the tiny little
320
00:16:49,908 --> 00:16:53,044
children grow up to be
full-size adults.
321
00:16:53,145 --> 00:16:55,813
But you don't see how
they got there, right?
322
00:16:55,914 --> 00:16:58,182
You don't see the intermediate
stages of growth.
323
00:16:58,283 --> 00:17:00,451
That would be really,
really weird, right?
324
00:17:00,552 --> 00:17:03,221
That is the case for
supermassive black holes.
325
00:17:03,322 --> 00:17:06,457
So it's like a universe
without teenagers.
326
00:17:06,558 --> 00:17:10,094
ROWE: Or that's how it looked,
until September 2020.
327
00:17:10,195 --> 00:17:13,531
Scientists studying
gravitational waves
328
00:17:13,632 --> 00:17:16,434
picked up the signal of
an extreme event
329
00:17:16,502 --> 00:17:18,403
in the distant universe.
330
00:17:18,504 --> 00:17:20,571
What researchers are looking for
331
00:17:20,672 --> 00:17:22,807
are things called
gravitational waves.
332
00:17:22,908 --> 00:17:25,710
They're like ripples
in space itself.
333
00:17:25,811 --> 00:17:29,213
Most signals sound
a little bit like a chirp.
334
00:17:29,314 --> 00:17:31,816
It's a noise that's
very characteristic.
335
00:17:31,917 --> 00:17:33,418
It goes a bit, like,
sort of whoop!
336
00:17:33,519 --> 00:17:35,620
[whooping noise]
337
00:17:35,721 --> 00:17:38,689
But this particular event
was so extreme
338
00:17:38,791 --> 00:17:41,459
and so sudden, it just sounded
more like a thud.
339
00:17:41,560 --> 00:17:43,494
[faint thud]
340
00:17:43,595 --> 00:17:46,597
ROWE: This faint thud
from halfway across the universe
341
00:17:46,698 --> 00:17:51,002
is music to the ears of
intermediate black hole hunters,
342
00:17:51,103 --> 00:17:53,971
because its pitch
can mean only one thing.
343
00:17:54,073 --> 00:17:57,875
This could only have been
created by two
344
00:17:57,976 --> 00:18:02,246
really massive black holes
colliding into each other
345
00:18:02,347 --> 00:18:04,982
and producing
a combined black hole with
346
00:18:05,084 --> 00:18:10,955
a mass that's 142 times
the mass of our sun.
347
00:18:11,056 --> 00:18:13,624
So that, is for the first time,
348
00:18:13,759 --> 00:18:17,628
getting into this intermediate
mass black hole regime.
349
00:18:17,729 --> 00:18:20,198
ROWE:
This is the first confirmed
350
00:18:20,299 --> 00:18:23,468
observation of
an intermediate black hole.
351
00:18:23,569 --> 00:18:26,037
Finding direct evidence
like this for
352
00:18:26,105 --> 00:18:30,041
an intermediate mass black
hole is absolutely fantastic.
353
00:18:31,410 --> 00:18:34,479
ROWE: Now that we're certain
intermediate black holes exist,
354
00:18:34,580 --> 00:18:37,348
could they help explain
the origin of supermassive
355
00:18:37,449 --> 00:18:39,183
black holes
in the early universe?
356
00:18:39,284 --> 00:18:43,621
These intermediate black holes
really could be
357
00:18:43,722 --> 00:18:46,591
the first seeds of
the supermassive black holes.
358
00:18:46,692 --> 00:18:50,394
You would need something like
that to form really big,
359
00:18:50,496 --> 00:18:54,031
really early to even begin to
explain these very massive,
360
00:18:54,133 --> 00:18:56,367
supermassive black holes
that have formed
361
00:18:56,468 --> 00:18:59,170
just a short time
after the Big Bang.
362
00:18:59,271 --> 00:19:04,142
ROWE: How do intermediate black
holes form in the first place?
363
00:19:04,243 --> 00:19:06,544
The recently discovered one
came from
364
00:19:06,645 --> 00:19:09,347
the collision of
two smaller black holes.
365
00:19:09,448 --> 00:19:13,317
They may also form
in giant clouds of gas.
366
00:19:13,418 --> 00:19:17,088
It could be that in
the earlier universe,
367
00:19:17,189 --> 00:19:21,192
you can just have large
clouds of gas that can lose
368
00:19:21,293 --> 00:19:23,427
enough energy quickly enough to
369
00:19:23,529 --> 00:19:28,666
just spontaneously collapse and
form a black hole of this size.
370
00:19:28,767 --> 00:19:32,236
HOPKINS: The enormous cloud of
gas contracts and gets denser
371
00:19:32,337 --> 00:19:35,840
and denser, the way it would if
it was starting to form stars.
372
00:19:35,941 --> 00:19:38,376
But it's somehow able to
remain coherent
373
00:19:38,477 --> 00:19:40,811
and collapse
into one giant object
374
00:19:40,913 --> 00:19:43,147
that forms an intermediate
mass black hole.
375
00:19:44,616 --> 00:19:48,219
ROWE: A giant gas cloud
undergoing a direct collapse
376
00:19:48,320 --> 00:19:50,922
down to
an intermediate mass black hole
377
00:19:51,023 --> 00:19:52,557
would be a rare sight.
378
00:19:55,994 --> 00:19:59,597
You think it would go giant
cloud, slowly collapsing,
379
00:19:59,698 --> 00:20:01,465
black hole, but instead,
380
00:20:01,567 --> 00:20:05,102
it's more like, giant cloud,
ahhhh!!!! Black hole.
381
00:20:06,171 --> 00:20:11,409
So one day, you see this
massive gas complex, and then
382
00:20:11,510 --> 00:20:13,611
you blink, and it's collapsed,
383
00:20:13,712 --> 00:20:17,181
and now you're face-to-face
with a big black hole.
384
00:20:17,282 --> 00:20:18,916
ROWE: At least,
that's the theory.
385
00:20:20,485 --> 00:20:22,687
Getting a black hole
to form from
386
00:20:22,788 --> 00:20:26,691
the direct collapse of
a gas cloud is very tricky.
387
00:20:26,792 --> 00:20:30,161
ROWE: Gas clouds tend
to split up and collapse
388
00:20:30,262 --> 00:20:33,464
into a multitude of stars --
Collapsing into
389
00:20:33,565 --> 00:20:36,667
one object would take
unique conditions.
390
00:20:37,936 --> 00:20:42,640
One possible scenario involves
two neighboring galaxies.
391
00:20:42,741 --> 00:20:45,843
The first, a young protogalaxy,
392
00:20:45,944 --> 00:20:49,247
a gas cloud yet to form stars.
393
00:20:49,314 --> 00:20:53,417
Next door sits a larger galaxy.
394
00:20:53,552 --> 00:20:55,753
It's forming so many stars,
395
00:20:55,854 --> 00:20:58,990
radiation is bursting out
all over its young neighbor.
396
00:21:00,058 --> 00:21:02,026
Because they're in
close proximity,
397
00:21:02,127 --> 00:21:04,528
the energy from the large galaxy
398
00:21:04,630 --> 00:21:08,132
prevents the smaller galaxy
from forming its stars,
399
00:21:08,233 --> 00:21:10,201
so that means that
it will continue
400
00:21:10,302 --> 00:21:13,871
to collapse in cloud form
before moving to
401
00:21:13,972 --> 00:21:15,873
star formation.
402
00:21:15,974 --> 00:21:18,509
ROWE: The gas cloud becomes
large and dense enough,
403
00:21:18,610 --> 00:21:21,512
the gravity eventually pulls
it in on itself.
404
00:21:22,881 --> 00:21:24,682
When it can't ignite into stars,
405
00:21:24,783 --> 00:21:28,019
the collapse creates
an intermediate mass black hole.
406
00:21:30,088 --> 00:21:32,790
SUTTER: I think this idea is
very intriguing.
407
00:21:32,891 --> 00:21:35,559
I don't know if it's
physically possible,
408
00:21:35,661 --> 00:21:36,761
but then again,
409
00:21:36,862 --> 00:21:39,063
there's a lot we don't know
about the early universe.
410
00:21:39,164 --> 00:21:44,068
ROWE: Whichever way intermediate
mass black holes form,
411
00:21:44,169 --> 00:21:47,571
they seem like a good way to
start explaining supermassive
412
00:21:47,673 --> 00:21:50,741
black holes
in the early universe.
413
00:21:50,842 --> 00:21:52,910
The question is, then,
how do they grow?
414
00:21:53,011 --> 00:21:55,680
How do you start
from this seed and end up,
415
00:21:55,781 --> 00:21:57,915
you know, with something that's
a billion times the mass of
416
00:21:58,016 --> 00:21:59,250
the sun?
417
00:21:59,351 --> 00:22:03,020
ROWE: Maybe early intermediate
mass black holes had
418
00:22:03,121 --> 00:22:04,555
enormous appetites,
419
00:22:04,656 --> 00:22:09,460
gorging themselves to
a supermassive state, feeding on
420
00:22:09,561 --> 00:22:13,431
the biggest meals
our universe can serve up.
421
00:22:13,532 --> 00:22:18,336
♪♪
422
00:22:26,278 --> 00:22:28,746
ROWE: Astronomers want
to know how the earliest
423
00:22:28,847 --> 00:22:32,316
supermassive black holes got
so big so quickly.
424
00:22:35,487 --> 00:22:37,555
Could they have started
as intermediate
425
00:22:37,656 --> 00:22:41,492
mass black holes that devoured
supersized meals?
426
00:22:42,861 --> 00:22:45,930
It's possible that these
intermediate mass black holes
427
00:22:46,031 --> 00:22:49,266
could form in an exceptionally
rare environment where it can
428
00:22:49,368 --> 00:22:52,670
accrete new material
at an enormously high rate.
429
00:22:54,539 --> 00:22:56,207
ROWE: So far,
we only have direct
430
00:22:56,308 --> 00:23:00,144
evidence of one intermediate
mass black hole,
431
00:23:00,245 --> 00:23:04,415
and we can't yet detect
how it eats and grows.
432
00:23:04,516 --> 00:23:08,352
But we could look at much
larger black holes for clues.
433
00:23:09,688 --> 00:23:13,391
In 2019, astronomers searched
for supermassive
434
00:23:13,492 --> 00:23:16,594
black holes that are
actively feeding.
435
00:23:16,695 --> 00:23:18,763
They pinpointed 12 quasars
436
00:23:18,864 --> 00:23:21,432
from the beginning of
the cosmos.
437
00:23:21,533 --> 00:23:23,467
HOPKINS: Quasars are among
the brightest objects
438
00:23:23,568 --> 00:23:24,902
we know of in the universe.
439
00:23:25,003 --> 00:23:28,339
And they're what happens when
a supermassive black hole at
440
00:23:28,440 --> 00:23:30,741
the center of a galaxy
is swallowing
441
00:23:30,842 --> 00:23:34,078
up gas and dust, and that
generates a tremendous amount
442
00:23:34,179 --> 00:23:37,181
of energy and luminosity
that we can see.
443
00:23:37,282 --> 00:23:39,483
ROWE: Surrounding
these early galaxies are
444
00:23:39,584 --> 00:23:43,254
enormous gas reservoirs called
hydrogen halos.
445
00:23:43,355 --> 00:23:45,189
PLAIT: This is great,
because that acts
446
00:23:45,290 --> 00:23:48,292
as fuel for those supermassive
black holes.
447
00:23:48,393 --> 00:23:51,729
Cold gas can stream into those
black holes and feed them.
448
00:23:51,830 --> 00:23:54,432
ROWE:
These huge halos of cold gas
449
00:23:54,533 --> 00:23:58,335
are also the building blocks
of stars.
450
00:23:58,437 --> 00:24:00,638
TREMBLAY: These enormous,
pristine halos
451
00:24:00,739 --> 00:24:02,940
of hydrogen around
early galaxies,
452
00:24:03,041 --> 00:24:08,112
they're gonna be reservoirs
to power star formation.
453
00:24:08,213 --> 00:24:10,948
ROWE: Star formation
is a violent process
454
00:24:11,049 --> 00:24:13,584
that can create turbulence
in a galaxy.
455
00:24:13,685 --> 00:24:17,822
That turbulence makes the gas
fall toward the black hole,
456
00:24:17,923 --> 00:24:21,325
and then that makes
the black hole even bigger.
457
00:24:21,426 --> 00:24:24,595
ROWE: Hydrogen halos
might have spoon fed
458
00:24:24,696 --> 00:24:26,697
early supermassive black holes.
459
00:24:26,798 --> 00:24:29,967
This process may have
also helped
460
00:24:30,068 --> 00:24:33,370
intermediate mass black holes
grow quickly.
461
00:24:33,472 --> 00:24:37,074
Could the largest
black holes show us
462
00:24:37,175 --> 00:24:39,777
other, more drastic ways
to put on weight?
463
00:24:43,181 --> 00:24:47,117
In October 2019,
astronomers used telescopes to
464
00:24:47,219 --> 00:24:52,456
explore a remarkably clear
galaxy called M77.
465
00:24:52,557 --> 00:24:55,326
Because this galaxy
is so near to us,
466
00:24:55,427 --> 00:24:59,196
we can study its central engine
in really exquisite detail at
467
00:24:59,297 --> 00:25:01,632
very, very fine resolution.
468
00:25:01,733 --> 00:25:02,967
SUTTER: Not only do you see
469
00:25:03,068 --> 00:25:04,869
the bright core,
the bright nucleus,
470
00:25:04,970 --> 00:25:07,171
but you can see spiral arms.
471
00:25:07,272 --> 00:25:09,507
You can see structures
in the galaxy.
472
00:25:09,608 --> 00:25:13,611
You can see how the whole
galaxy is arranged.
473
00:25:13,712 --> 00:25:16,146
ROWE:
When we examined M77's central
474
00:25:16,248 --> 00:25:20,050
supermassive black hole,
we saw something extraordinary.
475
00:25:20,151 --> 00:25:23,087
Its food was coming
not from one,
476
00:25:23,188 --> 00:25:26,957
but two accretion disks
spinning in
477
00:25:27,058 --> 00:25:28,893
opposite directions.
478
00:25:28,994 --> 00:25:31,428
Normally around a black hole,
all of the gas is spinning in
479
00:25:31,530 --> 00:25:32,463
roughly the same direction,
480
00:25:32,564 --> 00:25:34,965
and that creates kind of
a slow infall of gas
481
00:25:35,066 --> 00:25:36,734
and slow feeding -- here,
482
00:25:36,835 --> 00:25:38,168
we've got a case where
some of it's going
483
00:25:38,270 --> 00:25:41,038
one way, the other is going
the other way.
484
00:25:41,139 --> 00:25:44,308
This is very unstable and can
create opportunities for lots
485
00:25:44,442 --> 00:25:47,978
of gas to get gobbled up
by that black hole.
486
00:25:48,079 --> 00:25:50,214
ROWE: The material in the disks
487
00:25:50,315 --> 00:25:54,385
is one enormous
ready-to-eat meal,
488
00:25:54,486 --> 00:25:57,521
but dinner will not be served
until the outer disk
489
00:25:57,622 --> 00:25:58,789
slows down.
490
00:25:58,890 --> 00:26:01,125
HOPKINS: If there's a black hole
at the center of a galaxy,
491
00:26:01,226 --> 00:26:02,927
and you're orbiting around it
492
00:26:03,028 --> 00:26:05,162
fast enough to maintain
your orbit,
493
00:26:05,263 --> 00:26:06,897
you're never going to fall in.
494
00:26:06,998 --> 00:26:09,567
You're just going to orbit
forever, and you're just going
495
00:26:09,668 --> 00:26:11,001
to spin around,
just like the way the Earth
496
00:26:11,102 --> 00:26:12,403
is going around the sun.
497
00:26:12,504 --> 00:26:14,805
What needs to happen
if you wanna fall in,
498
00:26:14,906 --> 00:26:17,408
is to slow down your speed.
499
00:26:17,509 --> 00:26:20,411
ROWE: The outer accretion disk
will gradually slow down
500
00:26:20,512 --> 00:26:23,213
and orbit more tightly against
the inner disk.
501
00:26:23,315 --> 00:26:26,984
Dangerous collisions of
the counter-rotating
502
00:26:27,085 --> 00:26:29,620
material will start to occur.
503
00:26:29,721 --> 00:26:32,256
SUTTER: The double accretion
disk is like drinking
504
00:26:32,357 --> 00:26:34,825
from two soda fountains at
the same time.
505
00:26:34,926 --> 00:26:36,226
It's great while it lasts,
506
00:26:36,328 --> 00:26:39,296
but you're building up some
serious gas that is just gonna
507
00:26:39,397 --> 00:26:41,131
blow the whole thing away.
508
00:26:41,232 --> 00:26:43,067
ROWE:
In just a few 100,000 years,
509
00:26:43,168 --> 00:26:46,270
the double disks will
catastrophically collide,
510
00:26:46,371 --> 00:26:49,006
and their entire contents
will fall
511
00:26:49,107 --> 00:26:52,676
into the central
supermassive black hole.
512
00:26:52,777 --> 00:26:55,512
It will devour everything
in one gulp,
513
00:26:55,614 --> 00:26:58,882
generating a colossal
cosmic burp.
514
00:27:06,424 --> 00:27:10,828
In February of 2020,
in the Ophiuchus Galaxy Cluster,
515
00:27:10,929 --> 00:27:14,164
we saw the damage
a cosmic burp can do.
516
00:27:16,301 --> 00:27:19,236
PLAIT: The Ophiuchus Galaxy
Cluster is a collection of
517
00:27:19,337 --> 00:27:22,573
a huge number of galaxies,
all bound together by gravity.
518
00:27:22,674 --> 00:27:25,576
And there's gas in between
these galaxies.
519
00:27:25,677 --> 00:27:27,745
And when astronomers
looked at that gas in detail,
520
00:27:27,846 --> 00:27:31,148
what they found was a huge
arcing structure in it that
521
00:27:31,249 --> 00:27:34,018
they realized was
the edge of a cavity.
522
00:27:37,322 --> 00:27:40,891
SUTTER: There is a massive hole
in the gas that is
523
00:27:40,992 --> 00:27:45,596
over 15 times bigger than
the entire Milky Way Galaxy.
524
00:27:45,697 --> 00:27:52,269
Something frightening had to
happen to carve this void out.
525
00:27:52,370 --> 00:27:56,740
PLAIT: The size of this bubble
is kind of stomping my brain.
526
00:27:56,841 --> 00:27:58,142
We are talking about
527
00:27:58,243 --> 00:28:03,747
a hole in this gas that is over
a million light-years wide.
528
00:28:03,848 --> 00:28:05,582
ROWE: The burp that created
this cavity
529
00:28:05,684 --> 00:28:08,585
must have been
astoundingly powerful.
530
00:28:08,687 --> 00:28:10,821
PLAIT: There are a lot
of ideas about this,
531
00:28:10,922 --> 00:28:13,390
but there's only one that
really can explain it.
532
00:28:13,491 --> 00:28:15,259
And that's
a supermassive black hole.
533
00:28:16,728 --> 00:28:20,764
A supermassive black hole
that suddenly got very greedy.
534
00:28:21,833 --> 00:28:25,703
In order to drive an energetic
event like this,
535
00:28:25,804 --> 00:28:29,239
the black hole needs to eat --
Not just one meal.
536
00:28:29,340 --> 00:28:34,411
It needs to eat thousands of
meals at the exact same time.
537
00:28:34,512 --> 00:28:37,514
It needs to go
to an all-you-can-eat
538
00:28:37,615 --> 00:28:39,616
intergalactic buffet.
539
00:28:39,718 --> 00:28:41,652
Sometime in the distant past,
540
00:28:41,753 --> 00:28:46,957
this black hole must have had
a huge episode of just gorging
541
00:28:47,058 --> 00:28:50,094
on material falling in --
That got superhot,
542
00:28:50,195 --> 00:28:53,664
blew out a tremendous
amount of material in jets,
543
00:28:53,765 --> 00:28:56,767
beams that shot out
from the poles of the disk.
544
00:28:56,868 --> 00:29:00,637
And that's what basically
pushed its way out of that gas,
545
00:29:00,739 --> 00:29:03,140
forming this enormous cavity.
546
00:29:03,241 --> 00:29:06,810
ROWE: The colossal cosmic burp
pushed food far
547
00:29:06,911 --> 00:29:09,813
away from the supermassive
black hole, ending
548
00:29:09,914 --> 00:29:13,350
its all-you-can-eat binge
and stopping its growth.
549
00:29:14,452 --> 00:29:17,521
If an intermediate mass
black hole was this greedy,
550
00:29:17,622 --> 00:29:20,557
it would come to a similar end.
551
00:29:20,658 --> 00:29:24,762
It's no way to gain weight
and become supermassive.
552
00:29:24,863 --> 00:29:27,164
This is probably
not the way the earliest
553
00:29:27,265 --> 00:29:31,001
supermassive black holes grew
to such enormous size.
554
00:29:31,102 --> 00:29:33,737
ROWE: Is there another way
supermassive black holes
555
00:29:33,838 --> 00:29:34,972
could have formed
556
00:29:35,073 --> 00:29:37,741
in the early universe
without having to overeat?
557
00:29:39,110 --> 00:29:43,514
Maybe black holes smashed
their way to being giant-sized.
558
00:29:45,083 --> 00:29:47,885
[explosion blasts]
559
00:30:00,365 --> 00:30:02,866
ROWE: November 2018.
560
00:30:02,967 --> 00:30:04,968
Astronomers scanning hundreds of
561
00:30:05,069 --> 00:30:08,205
nearby galaxies in infrared
light spot
562
00:30:08,306 --> 00:30:10,440
something extraordinary.
563
00:30:12,977 --> 00:30:16,547
Some galaxies had not one
supermassive black hole,
564
00:30:16,648 --> 00:30:18,215
but two.
565
00:30:20,652 --> 00:30:22,986
Are these pairs
a clue to how supermassive
566
00:30:23,087 --> 00:30:27,291
black holes in the infant
universe got so big so fast?
567
00:30:28,660 --> 00:30:32,696
Seeing these infrared images
showing pairs of supermassive
568
00:30:32,797 --> 00:30:35,532
black holes at the centers
of galaxies
569
00:30:35,633 --> 00:30:39,102
and showing that
this could be very common
570
00:30:39,204 --> 00:30:41,638
just is mind-blowing to me.
571
00:30:41,739 --> 00:30:45,209
The reason we see pairs of
supermassive black holes
572
00:30:45,310 --> 00:30:48,545
is because two galaxies
merged together.
573
00:30:48,646 --> 00:30:51,748
MINGARELLI: In our picture of
how the universe works,
574
00:30:51,850 --> 00:30:56,687
galaxies start off as smaller
galaxies and grow by merging
575
00:30:56,788 --> 00:30:58,155
with other galaxies.
576
00:30:58,256 --> 00:31:00,891
So they'll be whooshing
around each other
577
00:31:00,992 --> 00:31:03,093
and tearing each other up.
578
00:31:03,194 --> 00:31:05,095
It's actually quite violent.
579
00:31:05,196 --> 00:31:08,265
ROWE: When galaxies merge,
we think their central
580
00:31:08,366 --> 00:31:11,068
supermassive black holes
also merge,
581
00:31:11,169 --> 00:31:14,338
smashing into each other
and combining to build
582
00:31:14,439 --> 00:31:16,273
a larger black hole.
583
00:31:16,374 --> 00:31:18,575
Galaxy-scale mergers
can be one of the most
584
00:31:18,676 --> 00:31:22,112
efficient growth mechanisms
for supermassive black holes.
585
00:31:23,548 --> 00:31:25,449
ROWE: Maybe,
in the early universe,
586
00:31:25,550 --> 00:31:28,619
black holes of stellar
or intermediate mass
587
00:31:28,720 --> 00:31:31,822
merged repeatedly,
getting heavier
588
00:31:31,923 --> 00:31:35,792
and heavier until
they became super massive.
589
00:31:38,062 --> 00:31:39,730
STRAUGHN: We don't
really know how common
590
00:31:39,831 --> 00:31:42,599
supermassive black hole mergers
were in the early universe,
591
00:31:42,700 --> 00:31:45,269
but we think they were more
common than they are today,
592
00:31:45,370 --> 00:31:48,038
because galaxies were
closer together.
593
00:31:48,139 --> 00:31:51,875
ROWE: It would have taken
millions of mergers to build up
594
00:31:51,976 --> 00:31:55,746
the largest supermassive
black holes we see today,
595
00:31:55,847 --> 00:31:57,981
which could have been
a tall order.
596
00:32:03,888 --> 00:32:05,989
There's another problem, too.
597
00:32:06,090 --> 00:32:07,891
We've never witnessed
a supermassive
598
00:32:07,992 --> 00:32:09,726
black hole merger in the act.
599
00:32:09,827 --> 00:32:13,030
We've seen supermassive black
holes on their way to merging,
600
00:32:13,097 --> 00:32:16,466
and we've seen ones that we
think had gone through mergers.
601
00:32:16,567 --> 00:32:19,169
But we haven't caught one
in the moment.
602
00:32:19,270 --> 00:32:22,005
ROWE: As supermassive
black holes start merging,
603
00:32:22,106 --> 00:32:24,074
they spiral around each other,
604
00:32:24,175 --> 00:32:27,377
getting faster and faster
the closer they get.
605
00:32:29,480 --> 00:32:31,648
But for them
to finally merge together
606
00:32:31,749 --> 00:32:33,784
into a single black hole,
607
00:32:33,885 --> 00:32:36,553
they need to lose what
astronomers call
608
00:32:36,654 --> 00:32:38,655
orbital energy.
609
00:32:38,756 --> 00:32:42,326
The merger of supermassive
black holes means that
610
00:32:42,427 --> 00:32:43,927
their orbits have to decay
611
00:32:44,028 --> 00:32:45,929
for them to get closer
and closer together.
612
00:32:46,030 --> 00:32:48,231
So in order
for an orbit to decay,
613
00:32:48,333 --> 00:32:51,168
that orbital energy
has to go somewhere.
614
00:32:51,269 --> 00:32:52,669
ROWE: To lose energy,
615
00:32:52,770 --> 00:32:56,473
the merging supermassive black
holes start disrupting
616
00:32:56,574 --> 00:32:58,842
the orbits of nearby stars,
617
00:32:58,943 --> 00:33:01,712
throwing them off their paths.
618
00:33:01,813 --> 00:33:04,181
HOPKINS: So something small
and puny that weighs
619
00:33:04,282 --> 00:33:07,918
just one sun like our own star
will often get in
620
00:33:08,019 --> 00:33:10,687
the path of these two
and just get rocketed out,
621
00:33:10,788 --> 00:33:15,726
potentially unbound and flung
out of the galaxy entirely.
622
00:33:15,827 --> 00:33:18,061
ROWE: Each time
the supermassive black holes
623
00:33:18,162 --> 00:33:21,965
fling out a star,
they lose more orbital energy.
624
00:33:22,066 --> 00:33:24,468
They get closer and closer.
625
00:33:24,569 --> 00:33:26,503
But eventually,
they kicked out all the stars.
626
00:33:26,604 --> 00:33:28,338
There's nothing left.
627
00:33:28,439 --> 00:33:30,707
ROWE: The merger stalls.
628
00:33:30,808 --> 00:33:33,076
Like two sweethearts
at a high school prom,
629
00:33:34,479 --> 00:33:38,882
the supermassive black holes
dance as close as they can,
630
00:33:38,983 --> 00:33:41,585
but physical contact
is not allowed.
631
00:33:43,554 --> 00:33:46,023
So these two black holes
could end up spiraling
632
00:33:46,124 --> 00:33:49,159
around each other for billions
and billions of years.
633
00:33:49,260 --> 00:33:51,194
This is called the final
parsec problem.
634
00:33:54,565 --> 00:33:57,834
MINGARELLI: In 1980,
there was a famous paper,
635
00:33:57,935 --> 00:34:00,003
which addressed this issue that
636
00:34:00,104 --> 00:34:02,272
supermassive black holes
can only get to
637
00:34:02,373 --> 00:34:05,776
within about one parsec, or
three light-years, of each other
638
00:34:05,877 --> 00:34:10,614
before they can't merge
or they stall.
639
00:34:10,715 --> 00:34:14,017
We believe that supermassive
black holes must merge.
640
00:34:14,118 --> 00:34:17,054
We know that galaxies merge,
and so if the black holes
641
00:34:17,155 --> 00:34:19,656
didn't merge, we'd see lots of
black holes floating around.
642
00:34:19,757 --> 00:34:21,458
And we don't -- there's always
one in the middle.
643
00:34:21,559 --> 00:34:23,226
So how do they merge?
644
00:34:24,796 --> 00:34:27,931
ROWE: In 2019, we found
something that appears
645
00:34:28,032 --> 00:34:30,967
to solve
the final parsec problem --
646
00:34:31,069 --> 00:34:33,303
A galaxy in the middle
of a merger
647
00:34:33,404 --> 00:34:36,573
that contains not two
supermassive black holes,
648
00:34:36,641 --> 00:34:38,308
but three.
649
00:34:38,409 --> 00:34:40,710
MINGARELLI: Three supermassive
black holes.
650
00:34:40,812 --> 00:34:42,279
Now that's really cool.
651
00:34:42,380 --> 00:34:44,848
Sometimes you can have
three galaxies
652
00:34:44,949 --> 00:34:48,085
that are merging together in
a galaxy cluster.
653
00:34:48,186 --> 00:34:50,387
Then you have three
supermassive black holes.
654
00:34:50,488 --> 00:34:51,621
At this point is,
655
00:34:51,722 --> 00:34:53,457
it's virtually
impossible for there to be
656
00:34:53,558 --> 00:34:55,692
a final parsec problem.
657
00:34:55,793 --> 00:34:58,829
ROWE: Here's how a third
black hole solves the final
658
00:34:58,930 --> 00:35:00,864
parsec problem.
659
00:35:00,965 --> 00:35:04,201
Two of the black holes orbit
closer and closer,
660
00:35:04,302 --> 00:35:07,304
ejecting stars to lose energy.
661
00:35:07,405 --> 00:35:10,607
Black hole number three
joins the action.
662
00:35:10,708 --> 00:35:13,243
Its gravitational pull
takes even
663
00:35:13,311 --> 00:35:15,846
more energy
from the orbiting pair.
664
00:35:15,947 --> 00:35:21,785
Eventually, they lose enough
orbital energy to collide.
665
00:35:21,886 --> 00:35:25,689
OLUSEYI: That third supermassive
black hole is just what's needed
666
00:35:25,756 --> 00:35:27,757
to transfer energy away from
667
00:35:27,859 --> 00:35:31,428
the two merging black holes
so that they can now merge into
668
00:35:31,529 --> 00:35:34,397
one single supermassive
black hole.
669
00:35:34,499 --> 00:35:37,534
ROWE: Triple black hole events
may explain how
670
00:35:37,635 --> 00:35:40,737
the earliest supermassive
black holes grew
671
00:35:40,838 --> 00:35:42,305
to such enormous size.
672
00:35:42,406 --> 00:35:47,544
We've suspected
that three black holes
673
00:35:47,645 --> 00:35:51,848
may be necessary in order
to get black holes to merge,
674
00:35:51,949 --> 00:35:54,084
but we've never had
any evidence for it.
675
00:35:54,185 --> 00:35:57,587
But now, this might provide
a direct picture
676
00:35:57,688 --> 00:36:02,325
of three black holes
caught in the act itself.
677
00:36:02,426 --> 00:36:05,595
If we have a picture
of this happening now,
678
00:36:05,696 --> 00:36:09,866
then it certainly happened in
the early universe and might
679
00:36:09,967 --> 00:36:14,204
explain how the biggest black
holes got so big so quickly.
680
00:36:15,706 --> 00:36:18,275
ROWE: Final proof will come
when we witness a merger
681
00:36:18,376 --> 00:36:19,342
being completed.
682
00:36:20,678 --> 00:36:25,382
Scientists are also
investigating invisible forces
683
00:36:25,483 --> 00:36:26,983
at the beginning of
the universe.
684
00:36:27,051 --> 00:36:29,886
Did something we can't see boost
685
00:36:29,987 --> 00:36:33,023
the size of the first
supermassive black holes?
686
00:36:43,968 --> 00:36:47,470
ROWE: One of the greatest
mysteries in cosmology is how
687
00:36:47,572 --> 00:36:53,043
the first supermassive black
holes got so large so quickly.
688
00:36:53,144 --> 00:36:56,780
We suspect mergers could help
explain their size,
689
00:36:56,881 --> 00:36:59,382
and we know all types
of black holes
690
00:36:59,483 --> 00:37:01,618
can grow by feeding,
691
00:37:01,719 --> 00:37:03,687
but we need more clues.
692
00:37:03,788 --> 00:37:07,924
There's still so much we don't
know about the early universe.
693
00:37:08,025 --> 00:37:10,293
SUTTER: The further out
we look in the universe,
694
00:37:10,394 --> 00:37:13,129
the less familiar
the universe becomes.
695
00:37:13,231 --> 00:37:19,436
And so the more and more
interesting and new physics
696
00:37:19,537 --> 00:37:22,672
you need to involve in order
to explain these very
697
00:37:22,773 --> 00:37:25,208
strange observations.
698
00:37:25,309 --> 00:37:27,043
ROWE:
The puzzle of fast-growing,
699
00:37:27,144 --> 00:37:30,880
supermassive black holes in
the infant universe now takes
700
00:37:30,982 --> 00:37:34,484
physicists somewhere new,
to the little
701
00:37:34,585 --> 00:37:37,387
understood realm of
magnetic fields.
702
00:37:38,789 --> 00:37:41,157
The thing about magnetic fields
is they're hard.
703
00:37:41,259 --> 00:37:43,360
They're hard to calculate,
they're hard to understand.
704
00:37:43,461 --> 00:37:45,862
They're sort of the elephant
in the room for astronomers.
705
00:37:45,963 --> 00:37:47,364
We know they're there, but we'd
706
00:37:47,465 --> 00:37:49,532
really rather not talk
about them.
707
00:37:49,634 --> 00:37:52,402
It's only recently that
people are incorporating
708
00:37:52,503 --> 00:37:55,972
magnetic fields into their
models of galaxy formation,
709
00:37:56,073 --> 00:38:00,010
and therefore, maybe it's under
the influence of these fields
710
00:38:00,111 --> 00:38:02,846
that somehow these supermassive
black holes are formed.
711
00:38:04,315 --> 00:38:07,017
ROWE: To investigate how
magnetic fields influenced
712
00:38:07,118 --> 00:38:09,052
early supermassive black holes,
713
00:38:09,153 --> 00:38:12,055
we must look back
at the very beginning.
714
00:38:12,156 --> 00:38:15,125
Soon after the Big Bang,
715
00:38:15,226 --> 00:38:18,695
the first particles form,
cool, and become
716
00:38:18,796 --> 00:38:20,597
electrically charged.
717
00:38:20,698 --> 00:38:21,931
Things were very different,
718
00:38:22,033 --> 00:38:23,667
radically different
than they are now.
719
00:38:23,768 --> 00:38:25,468
Particles were whizzing
by each other.
720
00:38:25,569 --> 00:38:26,870
Everything was charged.
721
00:38:26,971 --> 00:38:29,372
It was just a very
different landscape.
722
00:38:29,473 --> 00:38:32,575
ROWE: There are no stars yet,
not even atoms.
723
00:38:32,677 --> 00:38:35,745
But some scientists think
moving charged
724
00:38:35,846 --> 00:38:39,482
particles created
the first magnetic fields.
725
00:38:39,583 --> 00:38:40,784
Magnetic fields were essentially
726
00:38:40,885 --> 00:38:42,952
everywhere in the
early universe.
727
00:38:43,054 --> 00:38:45,855
PONTZEN: Those magnetic fields
would have extended extremely
728
00:38:45,956 --> 00:38:49,192
large distances,
like a very finely
729
00:38:49,293 --> 00:38:52,128
spun web all through
the early universe.
730
00:38:53,364 --> 00:38:58,234
ROWE: Gradually, atoms form
and gather into clouds of gas.
731
00:38:58,336 --> 00:39:00,103
These will become the first
732
00:39:00,204 --> 00:39:04,808
galaxies and their
supermassive black holes.
733
00:39:04,909 --> 00:39:08,111
During this time,
magnetic fields change.
734
00:39:08,212 --> 00:39:11,614
They bunch together
around the forming galaxies.
735
00:39:11,716 --> 00:39:12,882
But we don't know how.
736
00:39:12,983 --> 00:39:15,151
PONTZEN: The thing
with magnetic fields is
737
00:39:15,252 --> 00:39:17,387
they're extremely
hard to predict,
738
00:39:17,488 --> 00:39:21,124
and you need to do really hard
calculations that, even now,
739
00:39:21,225 --> 00:39:22,926
we're only just starting to do.
740
00:39:23,994 --> 00:39:27,130
ROWE: 2017 -- scientists design
741
00:39:27,231 --> 00:39:28,865
a groundbreaking computer model
742
00:39:28,966 --> 00:39:33,036
that simulates patterns of
magnetism developing over time.
743
00:39:33,137 --> 00:39:38,007
The images show lines of
magnetic force getting stronger
744
00:39:38,109 --> 00:39:41,411
and more focused across
a vast region of space.
745
00:39:41,512 --> 00:39:45,148
Some astronomers think these
emerging magnetic field lines
746
00:39:45,216 --> 00:39:49,686
help shape early galaxies and
the supermassive black holes
747
00:39:49,787 --> 00:39:51,354
at their cores.
748
00:39:51,455 --> 00:39:55,558
Magnetic fields have this
ability to push material around.
749
00:39:55,659 --> 00:39:59,629
So one possibility is
they could actually help push
750
00:39:59,730 --> 00:40:02,065
or funnel material in towards
751
00:40:02,166 --> 00:40:05,702
a growing black hole and help
it grow faster than it would
752
00:40:05,803 --> 00:40:07,404
do otherwise.
753
00:40:07,505 --> 00:40:10,240
ROWE: In today's universe,
we know magnetic fields
754
00:40:10,341 --> 00:40:13,843
around planets can
deflect dust particles.
755
00:40:13,944 --> 00:40:16,045
On much larger scales,
756
00:40:16,147 --> 00:40:19,349
matter may also have been
channeled into the centers of
757
00:40:19,450 --> 00:40:21,584
galaxies of the early universe.
758
00:40:21,685 --> 00:40:23,052
Were the magnetic fields of
759
00:40:23,154 --> 00:40:25,855
these early galaxies a conduit
that you could get matter
760
00:40:25,956 --> 00:40:28,691
dumped more and more into
the middle and maybe build up
761
00:40:28,793 --> 00:40:29,926
a really big black hole?
762
00:40:31,429 --> 00:40:33,463
ROWE: Scientists are just
starting to figure out
763
00:40:33,564 --> 00:40:37,801
the effects of magnetism at
the beginning of the universe,
764
00:40:37,902 --> 00:40:40,370
but it could have been one of
several mechanisms that
765
00:40:40,471 --> 00:40:42,605
influenced the size of early
766
00:40:42,706 --> 00:40:45,508
supermassive black holes.
767
00:40:45,609 --> 00:40:48,478
PONTZEN: We have lots of ideas
for how you might be able
768
00:40:48,579 --> 00:40:50,447
to form supermassive
black holes,
769
00:40:50,548 --> 00:40:54,184
but until we see actual
mechanisms in action, we just
770
00:40:54,285 --> 00:40:58,488
can't really say which of them
are the most important routes.
771
00:40:58,589 --> 00:41:01,891
ROWE: Maybe some other mechanism
we haven't even thought of
772
00:41:01,992 --> 00:41:03,359
explains how the early
773
00:41:03,461 --> 00:41:08,164
supermassive black holes
got so big so fast.
774
00:41:08,265 --> 00:41:10,767
Hopefully, one day,
these monsters of
775
00:41:10,868 --> 00:41:15,138
the cosmos will reveal
their secrets to us.
776
00:41:15,239 --> 00:41:18,508
Supermassive black hole
research is utterly
777
00:41:18,609 --> 00:41:21,077
mind-blowing to me.
I mean, this is so cool.
778
00:41:21,178 --> 00:41:23,513
MINGARELLI: It's important
to explain how these early
779
00:41:23,614 --> 00:41:25,582
supermassive black holes formed
780
00:41:25,683 --> 00:41:29,018
in order to have a really
concrete understanding of how
781
00:41:29,119 --> 00:41:30,353
the universe works.
782
00:41:32,223 --> 00:41:35,325
Supermassive black holes are
the great engines of cosmic
783
00:41:35,426 --> 00:41:38,361
change -- they're enormous
points of matter,
784
00:41:38,462 --> 00:41:40,663
and because
they're just so massive,
785
00:41:40,764 --> 00:41:43,433
they can sculpt
the evolution of galaxies.
786
00:41:43,534 --> 00:41:44,968
They're the master key
787
00:41:45,069 --> 00:41:48,338
to most of the unsolved
mysteries in physics.
788
00:41:48,439 --> 00:41:50,106
We have a chance here
789
00:41:50,207 --> 00:41:52,375
to understand supermassive
black holes
790
00:41:52,476 --> 00:41:55,345
so that we can understand
the formation of galaxies,
791
00:41:55,446 --> 00:41:58,147
the generation of stars like
our sun, and maybe even
792
00:41:58,249 --> 00:41:59,616
the appearance of life.
64545
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