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the study of extreme physics

brought us the bomb

it has taken us inside the violent death of a star

and now it has brought us face to face with the most destructive force in

nature a super massive black hole

how large how powerful can these monsters get

and what can they tell us about the extremes of time

and space

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the year was 1990. [Music] hope for a new age of scientific

discovery rose into orbit aboard the hubble space telescope [Music]

a technical flaw in its optics requiring astronauts to fly up to repair it would delay but not stop

this new age from dawning

in 1994 astronomers pointed the newly repaired hubble at one of its most

important targets a giant elliptical galaxy 50 million light years from earth called

m87

pushing deep into m87s core they glimpsed a powerful jet of super

hot gas extending 5 000 light years into space

with hubble's remarkable resolving power astronomers measured the speed of the gas racing

around the center they concluded the gravitational source

driving these motions is a black hole weighing in at 6.6

billion times the mass of our sun news of m87 joined a flood of

discoveries beaming down from hubble's instruments

the public was captivated by strange and majestic shapes captured from mysterious realms far

beyond earth

to scientists hubble was part of a quickly expanding arsenal of observing tools

a growing fleet of space observatories scanned the light of distant objects across the entire electromagnetic

spectrum [Music]

on the ground a new generation of giant telescopes with precision mirrors and dynamic

optics allowed observers to look deep into the universe [Music]

astronomers used to long nights of painstaking camera exposures were now a wash in data streaming in

from distant corners of the cosmos [Music]

a new vision of the universe emerged one defined by vast energy releases

titanic collisions [Music]

mysterious new forces [Music] and nature's strangest phenomenon

the black hole

once thought of as mere curiosities black holes have taken center stage in our

understanding of the universe and how it came to be

a black hole begins its life in the brilliant light of a dying star

within the folds of our galaxy the energy let loose by supernovae stirs the

celestial mix

shock waves from these explosions cause gas to condense then ignite

[Music] stars are born sometimes hundreds at a

time [Music]

intense stellar winds from these newborn stars sculpt majestic castles of gas

the great nebulae long admired by

astronomers

yet for the giant stars that set this process in motion the consequences are grim

back in the mid 1800s mariners plied southern seas by the light of a brilliant star

just off the plane of the galaxy in the constellation karina

for over a decade it was the second brightest star in the sky

astronomers have been studying it intensively ever since

the star named ada carine had undergone what's now known as the great eruption

an outburst that expelled two luminous lobes of gas that stretched some 12 trillion

kilometers from end to end [Music]

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astronomers recently found that ada carinae is actually two giant stars closely orbiting one

another to explain the extreme turbulence of

this scene scientists modeled the fierce hot winds roaring out of these two companions

[Music] the orbital motions of the two stars

allowed them to peg the larger one at 90 times the mass of the sun

eta carinae is a supernova waiting to happen

in time it will cease with convulsions then collapse and

explode throughout history our understanding of

space has been shaped by a handful of supernovae visible to the naked eye some

archaeologists believe this drawing depicts a supernova spotted by north american stargazers

in the year 1054. the same event was also recorded in

china korea and the middle east

in europe supernova sightings help dispel the prevailing belief that the heavens are static and

unchanging the astronomer tycho brahe saw one in the year 1572

i was led into such perplexity by the unbelievability of the thing he wrote that i began to doubt the faith

of my own eyes

in modern times astronomers have intensively studied the remnants of the 1054

explosion the famous crab nebula

[Music] waves of radiation roaring out of the explosion have etched circular patterns in the

surrounding gas seen here in radio

infrared [Music]

optical ultraviolet and x-ray light

you can see signs of a jet shooting out of the central region

this energy is coming from a tiny spinning object in the center the size of a city

this neutron star is not made of any elements but subatomic particles packed by

gravity into an ultra dense sphere [Music]

physicists think of it as a single huge atom it's roughly equivalent to packing

mount everest into a sugar cube

yet some dying stars meet a fate that is stranger still

in 1796 pierre simon the marquis de la place imagined a breed of dark stars so heavy

their gravity prevented any light from escaping [Music] this idea a head scratcher fell out of

favor for more than a century

isaac newton had described gravity as a force of attraction between two masses

early in the 20th century albert einstein's equations showed that gravity is actually the

distortion of space-time by massive objects

thus a planet or star or even a galaxy creates a gravitational well that will

bend the path of other objects or even beams of light

as the physicist john archibald wheeler later put it space-time tells matter how to move

matter tells space-time how to curve

in 1919 the now famous eddington expeditions set out to test this wild idea during a

solar eclipse [Music] their data showed that the sun's gravity

bent the path of starlight just as einstein had predicted

but also hiding in einstein's equations was a very strange prospect that

recalled pierre simon's speculation if an object is dense enough it will

bend a beam of light back onto itself causing that light to disappear

physicist carl schwarzfield director of the astrophysical observatory in potsdam germany

took this idea to its logical conclusion working as an artillery lieutenant on

the battlefront of world war one he stole moments to pour over einstein's new theory

as you see he wrote to einstein the war treated me kindly enough in spite of the heavy gunfire to allow

me to get away from it all and take this walk in the land of your ideas

schwarzeeld realized that objects could become so dense their mass would be packed into an

infinitesimal point a singularity

he calculated that these odd creations must be bounded by a larger spherical region

beyond which no light can escape the so-called event horizon

but how could such objects actually exist

in 1939 einstein himself wrote a paper that sought to prove that these strange objects

were impossible but just a few months later physicist

j robert oppenheimer and his graduate students published their own paper on the subject

taking a fresh look at the mathematics of collapsing stars they show that if the parent star is

sufficiently massive the force of the collapse will literally crush its core

down to a point an infinitely dense infinitely curved speck of pure

gravitational energy

oppenheimer went off to spearhead the design of the atomic bomb

having laid the foundations of the modern science of black holes

the atomic age brought a whole new focus on the study of extreme physics

the bomb was terrifying proof as einstein conjectured that a small amount of mass could

convert to a huge amount of energy researchers studied the enormous forces

released when atoms are split apart in chain reactions at the heart of

atomic and thermonuclear bombs

using advanced new computers developed to model and forecast these explosions astrophysicists

began probing the mechanisms at work deep inside stars where lighter elements

burn and fuse into heavier ones they saw how this can eventually lead

large stars to collapse and explode

this grim product of star death entered the popular imagination in 1967

when physicist john wheeler called it a black hole

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astronomers were already at work looking for these monsters

in 1964 a sounding rocket recorded a high-energy x-ray source in the southern

constellation of cygnus [Music] later satellites recorded a pulsing

rhythm in its light punctuated by outlandish bursts of energy [Music]

after pinpointing its exact location ground-based observatories detected a giant star

that could not by itself emit x-rays

astronomers deduced that cygnus x1 is a star with an unseen companion one

that is eating it alive enveloped in a halo of glowing gas

streaming in from the star that partner weighs in at 15 times the

mass of our sun the first confirmed black hole

[Music]

this computer simulation shows how a black hole makes its presence known

matter spiraling into the abyss forms what's called an accretion disc

the spinning motion generates powerful magnetic fields that whip up a hurricane of particles

and propel them from the poles at nearly the speed of light [Music]

if you were to fall into a star-sized black hole the pull of its gravity rises so sharply

you'd be stretched out until just your atoms remained what physicist stephen hawking once

called spaghettification [Music]

stellar evolution models suggest there could be as many as a billion black holes in our milky way alone

yet they are dwarfed by a far larger and far more powerful presence lurking in the very

core of the galaxy

[Music] the first hints of this presence came in

1932. the bell telephone company was concerned

about static interfering with what it saw as a revolutionary new technology

long-distance radio communications

the company tasked the radio astronomer karl jansky with finding the sources

using this ungainly radio receiver jansky methodically scanned the airwaves

he traced most of the static to thunderstorms some nearby and others far away

then on september 16 1932 he picked up a rumble that he could not

explain this particular noise appeared when the

antenna was pointed at the constellation sagittarius toward the center of the galaxy

it returned every 23 hours and 56 minutes exactly one earth day in relation to the

stars [Music] word of jjansky's findings got out

he assured the public it was not aliens seeking contact [Music]

but it would take another 30 years for astronomers to find out what it was

in the 1960s advanced radio telescopes began picking up signals from distant

space not knowing just what they were observers called them

quasi-stellar radio sources quasars for short

[Music] these bright bluish beacons emitted far greater energy than a star

one cosmic engine was driving them

radio astronomers found that some featured brilliant extensions originating in the centers of galaxies

and reaching millions of light years into space

looking at their light spectra researchers realized that these were actually jets of super hot gas speeding

away at hundreds of thousands of kilometers each second

could such a feature finally explain jansky's findings

it would take a new generation of giant telescopes to reveal the answer [Music]

just as the hubble space telescope began its sensational run several new observatories were

christened on the mountains in hawaii in the north and the andes

mountains in the south [Music]

two rival teams of astronomers each zeroed in on the galactic center to see what was

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there

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these teams each undertook a multi-decade effort to track a population of stars that seem

to orbit a concentrated source of energetic emission called sagittarius a star

finally in the spring of 2002 a star labeled s2 swooped in close accelerating to a

remarkable 18 million kilometers per hour

[Music] if its path near sagittarius a star proved erratic

astronomers would know the galactic center was packed with multiple massive objects

instead its path was smooth they concluded that s2 and its

companions must be orbiting a single object weighing several million times the mass of our sun

a supermassive black hole

this effort more than two and a half decades after it began was recognized with the nobel prize in

physics since that discovery astrophysicists

have been feeding additional observation data into their supercomputers to better understand

how clouds of gas flow around and into the monster and how its immense

gravity drives the motions of stars at the center of our galaxy

[Music] the star s2 will inevitably return to

the black hole the pull of gravity will cause its orbit

to shrink pulling it ever closer

astronomers recently caught a glimpse of what would then happen

a survey telescope in the andes mountains recorded the sudden brightening of a galaxy

in distant space astronomers at the european southern observatory

turned their telescopes toward the source [Music]

the light had come from a galaxy 215 million light years away astronomers tracked the

event through to its ultimate demise six months later

they deduced that a star had wandered a little too close to a supermassive black hole

the giant began to tear it apart turning the star into a river of hot gas

fueling a high-energy jet bright enough to be detected from earth

astronomers have long nurtured the hope of seeing a black hole directly

to understand its properties and how it disrupts the space around it

in recent years an international group of astronomers has been working on just such an

audacious goal like the eddington expeditions a century

before these scientists hope to test einstein's theories

only this time in the most extreme laboratory the universe has to offer a black hole

the idea was to adapt a technique developed over 60 years ago

called long baseline interferometry [Music]

by synchronizing radio telescopes all around our planet a team of 400 scientists and engineers

created a much larger virtual telescope with an aperture the diameter of earth

itself it has a resolution equivalent to being able to read a newspaper in paris

while sitting in new york

they call it the event horizon telescope

their goal to capture the first ever image of a black hole

their target the monster at the center of m87

probing deep into m87s luminous core the astronomers struck a delicate

balance between filtering out interstellar dust and finding the outlines

of their quarry at a radio wavelength of about one millimeter all the dust and gas

obscuring the monster faded away leaving this ghostly silhouette

a black hole an object that cannot by its very nature be seen

the event horizon telescope relies on a tool that has transformed the study of the universe

to make sense of the vast amount of data captured by the many receivers researchers developed a series of

computer simulations visualizing the complexity of the scene

here are some of the results the dark nucleus is the event horizon

a shadow left when the object's immense gravity slows all light to a stop

the singularity the black hole itself is hiding in the shadows

the visible ring marks the spinning accretion disk

it's brighter on one side because the gas there is spiraling towards the telescope its

photons piling up the light from material moving away

becomes dimmer as its wavelength stretches toward the red part of the electromagnetic spectrum

from a slightly more distant perspective you can see how a portion of the inflowing matter

is flung out in a fiery pulsating jet

m87 is a black hole of truly cosmic proportions

it has been bulking up for billions of years on a steady diet of gas dust planets

and stars but it's not the only billion solar mass

black hole out there or even the largest

[Music] the coma cluster is a dense grouping of

galaxies 321 million light years from earth

its center is occupied by a colossal elliptical galaxy cataloged as ngc 4889

it harbors a black hole estimated to be 21 billion times the mass of the sun

j2157 is even larger

at 34 billion times the mass of the sun this ultra massive black hole is 8 000

times larger than the one at our milky way's core

the largest black hole yet spotted ton 618 may weigh as much as 66 billion

of our suns it drives a super luminous quasar shining 140 trillion times brighter than

our star [Music] theoretically there is no limit to how

large a black hole can grow all it takes is time and the right circumstances

the building boom of ever larger telescope mirrors has given astronomers a whole new

vantage point on the life cycle of ultramassive black holes

here in the high northern deserts of chile they have been combing the early universe for dim clues of black holes on

the rise out in the southern constellation of leo

they spotted the most distant quasar yet observed just 770

million years after the big bang [Music]

the red dot is light energized by a black hole estimated at two billion times the mass

of the sun how did it form and what impact will it

have on its surroundings

to find out scientists have launched a major international effort to simulate the early evolution of the

universe

the action starts a few million years after the big bang gravity begins to draw hydrogen gas into

large halos and from there into concentrations dense enough for stars to form

as some stars die they give rise to black holes these primordial monsters

feed on in-rushing gas growing ever larger while blasting their

environments with fierce winds and jets [Music]

the scene shifts to visible light as the universe reaches its halfway point two galaxies

are beginning to form each with a central region densely packed with stars

gravity begins to draw the two into a cosmic embrace [Music]

the black holes at their centers will inevitably meet and merge the end result

a galaxy similar to our own with a super massive black hole hidden deep in its core

we now move to a much larger scale the action starts 500 million years

after the big bang matter coalesces in a spider web pattern

of filaments and dense knots

amid the formation of countless stars several larger galaxies develop

as they merge so do the black holes in their cores [Music]

a still larger view tracks the impact these supermassive black holes have on the surrounding universe

you can see bubbles rising quickly from the largest galaxies these are waves of super hot gas pushed

out by winds and jets powered by growing black holes

such outbursts seed the universe with elements generated by large stars and supernovae

elements that would one day come together in stars and planets like our own

[Music] by pushing outward huge volumes of gas

these hot bubbles slow the growth of their host galaxies while promoting the formation of smaller

galaxies like our milky way

[Music] quasars and the black hole jets powering

them are among the most energetic phenomenon known [Music]

this one spotted by the hubble space telescope in the early universe emits light 600 trillion times brighter

than our sun [Music]

and yet that hardly begins to describe the power unleashed when two supermassive black

holes collide

to find out what that will look like from earth scientists have simulated the moment just before two supermassive

black holes merge magnetic and gravitational forces heat

up the gas the pair is enveloped in ultraviolet

light super hot plasma flowing around and into the black holes

glows in x-ray light

[Music]

the intense gravity of the pair distorts and bends space time creating a lens

albert einstein hinted that the energy of such a collision goes far beyond the emission of

high-energy light his equations predicted that when massive bodies like black holes

accelerate or whip around each other they would disturb the normally smooth fabric of space-time

[Music] a series of powerful gravitational waves

would move outward like ripples on a pond

by the time these waves travel the breadth of the universe to reach us their energy will have nearly dissipated

[Music]

and yet scientists believe they have detected them

at the laser interferometry gravitational wave observatory known as ligo they have assembled

precision high-powered lasers and some of the most perfect large-scale

vacuum chambers ever created

the idea is that as a gravitational wave passes it will stretch and squeeze the distance

between mirrors placed at the ends of four kilometer long tubes

this distortion of space-time measured by lasers is incredibly subtle a thousand

times smaller than the nucleus of an atom

this ambitious undertaking decades in the making finally bore fruit in 2015.

the instruments at ligo and its european counterpart each recorded a signal consistent with

the merger of two black holes of 29 and 36 solar masses

[Music] scientists calculate that the collision converted the mass of up to three suns

to pure energy in the form of gravitational waves

ligo's founders would win the nobel prize for physics in 2017

this simulation shows the pattern of gravitational waves that the pair would have emitted in the final moments of the merger and

just after as the object spiral together the energy

carried by each successive wave rises for the briefest of moments to a hundred

billion trillion times the power of our sun [Music]

collisions like this are extremely rare but the universe is very large

as their sensitivity improves ligo and similar instruments will detect more and more such

reverberations in space-time

remarkably even this does not begin to describe the power

held within a black hole

[Music]

imagine a spaceship in the distant future on a rendezvous with a supermassive

black hole [Music]

because of the object's immense size the stretching force is small allowing the ship to survive as it falls

through the event horizon but not for long

as the ship spirals down it hits a wall of energy what scientists describe as the inner

horizon [Music]

at a black hole's event horizon matter accelerates to the speed of light

it is then whipped around so fast that some of it gets flung back out and into a collision with

inflowing matter

at the inner horizon the energy rises so sharply it may well reach nature's limit

equivalent perhaps to the big bang [Applause]

itself [Music]

fortunately for us gravity walls off such extremes behind the event horizon of black holes

[Music]

waiting long enough trillions upon trillions of years to a time when theory says all matter

and energy will likely fall inside black holes

[Music] gravity may well draw the entire

universe inside a single ultimate black hole

some theories suggest that it could erupt

in a flurry of matter and anti-matter

[Music] in gases that cool and coalesce into stars

[Music] explosions that give rise to black holes

[Music] galaxies that envelope and nurture them

while giving birth to solar systems like ours

[Music] and so here we sit on a planet that is

an infinitesimally small by-product of the universe at large

our imaginations though are unbounded

as we contemplate the strange and powerful forces that have shaped all we see

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so

you