《宇宙的誕生》- 國家地理頻道 (Birth of the Universe, National Geographic)

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Our universe, the galaxies, the solar system, our home planet earth
- land, sea, air, life
- where did they all come from?
Look up into space from our planet
and what you see is a vast cosmos - teaming with billions of stars and galaxies.
Turn back the clock over 13 billion years and our universe was a very different place,
back then it was small that it could fit inside the palm of your hand.
Form this infant universe everything would be created
- stars, galaxies and the building blocks of life itself.
the calcium in our bones, the iron in our blood
the atoms for the air we breathe - the water we drink
the raw materials for our cities and machines
Naked Science takes a journey through space and time
to discover how the universe was born
and how it created everything in our world
- and how eventually it will die.
Everything we see around us is made of matter - atoms and molecules.
Take this car - it's a 1956 Ford Fairlaine Convertible.
It's constructed from many different materials like steel, rubber and glass¡
Go deeper and these materials are made up from combinations of elements like iron, silicon, chromium and carbon
Each and every atom that makes up this car were created by our growing universe.
Physicist Laurence Krauss studies how the atoms we see on our planet have come to be here
We really are part stardust and part big bang dust.
Most of the atoms in our body are from the cores of stars
but some of them have been around from the earliest moments of the big bang.
So we really are truly cosmic individuals
Each and every atom was created over billions of years as our universe evolved.
So when we look at this car, of course, all the atoms in this car came from stellar explosions,
from supernova processes and from stellar evolution,
but they were created at different times during the evolution of the Universe
To understand how the universe made all the raw material we see here on Earth,
we need to take an incredible journey
and travel back through space and time to the moment our universe was born.
In the beginning there was nothing.
No space, no time
And then there was light.
Suddenly a tiny speck of light appears - it was infinitely hot.
Inside this tiny fireball was all of space
This was literally the beginning of time.
The cosmic clock was ticking - time could flow and space expand.
At the earliest moments of the big bang, if you take it back to T=zero,
everything in our universe, everything we can see, all the matter and all the energy in all of the galaxies
was once contained in a region smaller than the size of a single atom today,
The idea that our universe was once tiny originated from the brilliant work of American astronomer Edwin Hubble.
Back in the 1920's most astronomers believed that everything visible in the night sky were stars
and they were part of our galaxy - the Milky Way
But Hubble wasn't convinced.
He studied a swirling cloud of light called the Andromeda Nebula and showed that it was a star city
another galaxy far outside of our own galaxy
He showed that these 'other' galaxies were speeding away from ours
and the further away they were, the faster they seemed to be moving
The universe was expanding
and if the universe was expanding, then at some point in the past it must have been smaller
- much smaller
and that it must have had a beginning.
The idea of the 'Big Bang' was born.
Theoretical physicist David Spergel is a Big Bang expert
The Big Bang theory is not really a theory of how the Universe began;
it's really a theory of how the Universe evolved
No-one knows exactly what happened during the Big Bang
but scientists do know that a fraction of a second after the universe was born
this tiny super-hot fireball was already starting to expand
We don't know how the Universe began,
so we start our story when the Universe was a billionth of a billionth of a billionth of a billionth of a minute old
Pretty young, the Universe was the size of a marble
Less than a trillion trillionth of a second after the Big Bang
the marble sized universe was very unstable and underwent an enormous growth spurt.
During this period of incredibly rapid expansion,
Space itself was expanding faster than the speed of light.
In the same way that this hot glass ball inflates, so did the baby universe
expanding in all directions at once and as it expanded it cooled.
A trillion trillionth of a second after the Big Bang the Universe was small enough to fit inside the palm of your hand.
A tiny fraction of a second later it was the size of Mars
Another fraction of a second and the baby universe had grown to 80 times the size of the earth.
A trillionth of a second after the Big Bang and our newborn universe was still expanding
But it didn't contain matter - it was pure energy
Einstein's famous equation E=mc2 showed that mass and energy are interchangeable
It gave us the knowledge to build weapons of mass destruction.
It also revealed how the universe created the first matter.
When a nuclear bomb explodes
a tiny amount of matter is annihilated and converted into energy.
In the baby universe the exact opposite happened.
It converted pure energy into particles of matter.
But there was a problem.
The universe created both matter and its arch rival anti-matter
- and when these two met they obliterated each other.
The infant universe was a war zone - a battle to the death between matter and antimatter
If they mutually annihilated each other the universe would remain full of energy with no galaxies, stars, planets or life
Fortunately for us there was an imbalance.
For every 100 million anti-particles formed, there were 100 million and 1 particles of matter
But there was that one extra particle of matter left over in each volume,
and that was enough to account for everything we see in the universe today,
This tiny imbalance led to all matter we see in the universe
- galaxies, stars, planets, - even convertibles and ourselves.
Astrophysicist Carlos Frenk from Durham University in England explains.
We are a little bit of debris left over from the annihilation of matter and antimatter;
we're the leftovers of that process.
If the Universe had not developed this slight asymmetry between matter and antimatter
the Universe would have been completely boring, there would be no structure, there would be no galaxies, there would be no planets,
Quite what this newborn Universe was like has challenged cosmologists since the Big Bang was first put forward.
Now in one of the biggest laboratories on Earth
they are able to recreate the conditions that almost certainly existed an instant after the Big Bang.
It's called the Relativistic Heavy Ion Collider - RHIC for short
and it's located at the Brookhaven National Laboratory on Long Island.
It's like a time machine - taking us back to 10 millionths of a second after the Big Bang
Here scientists like Todd Satogata accelerate subatomic particles close to the speed of light and then smash them into each other.
The particles race around this 2.5 mile long circular tunnel in opposite directions 78,000 times a second¡
and then collide inside this giant detector - bigger than a 3 story house¡
When they smash into each other they generate incredible heat - just like the real infant universe
We believe the early universe was extremely hot billions of times hotter than the centre of the sun
and what you're doing smashing these nuclei together is melting matter, creating matter hot enough to give us a glimpse of what the very early universe was like
When the particles collide they break open and throw out a shower of even smaller particles
It's a bit like discovering what cars are made of by watching them smash into each other
You can race two race-cars together and smash them into each other head-on,
and when you do that multiple times you start to see different patterns coming out,
a tyre comes out here, a radiator comes out there,
and before long you can start to conclude that a race-car is made up of these certain pieces.
What the scientists at Brookhaven have discovered is that within these superheated collisions a completely new form of matter appears.
And this matter contradicts the previous theories on the nature of the early universe.
Because it's not a gas - it's a liquid.
It was super hot - 100,000,000 times hotter than the surface of the sun
There was so much energy inside the young universe that the particles vibrated so fast that it had no stickiness
there was no friction and it flowed perfectly.
This liquid is perfect, it has no viscosity, in some sense it would be the perfect motor oil except it's a trillion degrees hot.
Inside the collider this amazing liquid Universe exists for only a tiny fraction of a second.
The Brookhaven scientists have succeeded in recreating conditions that existed over 13 billion years ago
Despite the universe being a perfect liquid - it was in turmoil.
It was full of subatomic particles smashing into each other releasing more and more energy
There was so much energy that unless the particles slowed down they would never bond and create atoms
- the building blocks of matter
- and the universe would never create the galaxies and stars or even us.
The universe is now one millionth of a second old
and has expanded from smaller than the size of an atom to 8 times the size of the solar system
After the incredible turmoil of the first millionth of a second the Universe was now relatively calm
Over the next three minutes the expanding cosmos cooled sufficiently for protons and neutrons to bind together
and form the first atomic nuclei: hydrogen and helium.
These were not yet proper atoms
They were missing a vital ingredient - the electron
In the hot baby universe there were plenty of electrons around,
but there was still so much heat and energy the electrons were moving too fast to form bonds
And it would stay that way for over three hundred thousand years.
380,000 years after the Big Bang the universe had expanded to the size of the Milky Way.
It had cooled from billions of degrees Fahrenheit to a few thousand
As it cooled, the electrons slowed down.
The universe was now ready to make its first true elements.
One of the scientists who discovered this critical moment in the story of the universe was Arno Penzias.
1963, 30-year-old Penzias and his 27-year-old colleague Robert Wilson began work on a new antenna in New Jersey.
Initially they were only studying cosmic radio waves
- but they would stumble on one of the greatest discoveries of all time.
As they started to test their equipment, they detected an unexpected background noise
It was an additional signal and it appeared to be coming from the sky,
we eliminated very carefully the ground, even the solar system,
because we did this winter to summer, seasonal variation,
man-made sources of equipment, all these things were eliminated.
In desperation, the two scientists began to wonder whether the strange signal might have another, more earthly, origin
They found there were pigeons roosting in the antenna, and it was covered with droppings
They wondered if the pigeons were the source of the strange signal.
There was only one solution: the droppings and the pigeons would have to go
When we finally got around to removing the pigeon droppings, we also had to remove the pigeons
and that was a difficult problem because they turned out to want to come back and so we mailed them off to another site
But even with the troublesome pigeons gone, the mysterious signal would not disappear.
so we were left with the inescapable conclusion that this radiation was coming from the sky.
I could not account for it
The strange signal detected by Penzias and Wilson would turn out to be one of the most important scientific discoveries of all time
But the explanation for their mystery background noise starts not with sound - but with the birth of light
We usually take light for granted.
But in the early universe 13 billion years ago, we would see nothing at all.
Light was trapped. The universe was foggy.
But as the universe continued to expand and cool the electrons slowed down
Protons then grabbed these calmer electrons to form complete atoms of first hydrogen and then helium
The universe was suddenly much less crowded with electrons
The fog lifted and light was no longer trapped.
It hurtled out across the universe - creating a blinding burst of light.
Had we been there we would have suddenly seen this opaque Universe become transparent,
suddenly the fog would lift and we would see a flash of light coming from everywhere around us.
It must have been a spectacular moment.
Over time, this burst of light dimmed and cooled and became microwave radiation.
It was this faint 13 billion year old microwave signal that Penzias and Wilson picked up on their antenna.
What they heard was the quiet echo of the moment the universe formed the first atoms
It's really the light from the origin of the Universe
If you have an old FM receiver, ¡ if you tune between channels,
turn the knob and it doesn't capture it and pop to the station,
you get to a part where there's not, you hear a fffffff¡. that's what we call noise.
If you have a good radio set, one half of one percent of that fffff¡ is actually the sound of the Big Bang.
And we can also see the moment when the first elements were created
If our television is not tuned to a station, a tiny fraction of the noise is radiation from 13 billion years ago
But this radiation is not the only reminder of the birth of the Universe - even the water we drink is a memento
And it's kind of amazing to think that every time we take a drink of a glass of water,
we're drinking in atoms that have been around since the Big Bang - the hydrogen atom.
Over the next millions of years the young universe continued to expand, cool and get dark again
So far the Universe had only made hydrogen and helium atoms
but the world we live in is made from more than a hundred different kinds of elements
Without them the universe would remain a very boring place made up of only gas
a place where complex matter - like planets, cars and people could never develop.
The universe needed to get hydrogen and helium atoms to fuse.
And to do that it needed to make stars
The universe was now 200 million years old and billions of light years across.
Its temperature had dropped so far that it was colder than liquid nitrogen - minus 367 degrees Fahrenheit
It was also dark.
It would have remained a very gloomy place full of gas
but without galaxies, stars or planets if it hadn't been for one thing:
The baby Universe wasn't born perfect.
Carlos Frenk has created an amazing 3-D simulation of how the early universe evolved
It shows that when the Universe emerged from the Big Bang it was uneven.
Little cracks appeared which were very, very, very tiny, very, very small,
and it was this rash in the face of the baby Universe that later developed into the patterns that we see in the galaxies today
Without these cracks, the universe would have been a very dull place.
The first clues as to how these cracks developed into galaxies and stars
came when other scientists started to examine the Big Bang radiation first discovered by Penzias and Wilson
So Penzias and Wilson saw was this radiation was, as far as they can tell uniform,
What cosmologists then did for the next 25 years was work very hard to try to find tiny variations
And find them they did using WMAP
a space probe designed to detect and analyze in detail variations in the back ground Microwave radiation
Launched in 2001 the $150 million probe was fitted with some of the most sensitive instruments ever carried into space.
Our eyes detect only visible starlight
But WMAP can 'tune' into the invisible microwave radiation.
Once in orbit round the sun it picked up the faint radiation that has been rippling around the universe since the dawn of time.
So when we look at the cosmic background radiation
we're looking at this radiation that's been streaming towards us since half a million years after the Big Bang.
Initially the 'microwave universe' looked very dull and seemed to be the same everywhere
But when WMAP turned up the contrast: the results were spectacular.
The baby universe wasn't smooth and boring at all - it was full of fluctuations
These tiny fluctuations tell us what the variations in density, how much stuff there is, and how it varies from place to place
these denser regions are going to collapse to form clusters of galaxies and super-clusters and galaxies themselves
These low density regions, these will grow and become the empty regions between galaxies,
so this picture, really is our connection between the Universe when it was a baby half a million years old,
to the Universe today, 13.7 billion years old
These tiny imperfections in the fledgling Universe would become galaxies and stars
And this is one of the most amazing propositions in physics
the idea that galaxies like a Milky Way that contain a hundred million stars once began life as a tiny little crack in the fabric of the Universe
The material in these cracks was filled with swirling clouds of hydrogen atoms
The voids between the clouds grew bigger and bigger.
The gas clouds got denser and hotter.
Gravity pulled the gas clouds together on filaments - like beads on threads of a web - a cosmic web
Where the giant filaments formed large globs, stars and galaxies would grow.
As the Universe evolved, gases were able to condense into clouds which collapsed to form stars
The stars settled into a rotating disc that was later to become a spiral galaxy like the Milky Way.
Over millions of years the hydrogen atoms clumped together and heated up.
The atoms began fusing and releasing energy and the gas clouds started to burn brightly
Eventually a star was born.
All over the universe, millions of stars ignited for the first time.
The appearance of the first stars would have been a truly spectacular event
Had we been there we would have really seen fireworks,
individual, enormous flashes of light generated as the stars are born and burnt themselves out.
The universe has expanded many trillions of times its original size
It was full of new born stars made of hydrogen and helium.
These young stars were nothing like our own Sun
They were very unstable.
But it was their instability that would make the universe a more interesting place
because deep inside each new star something amazing was happening.
They were creating new elements
The idea that stars build atoms came from the British Astrophysicist Sir Fred Hoyle
- one of the greatest astronomers of the 20th century.
Hoyle didn't believe that the universe began in a single explosion.
In fact he coined the name "Big Bang" as a term of derision.
Hoyle wanted to know where the elements heavier than hydrogen and helium came from
He figured out that stars acted like nuclear reactors
working a bit like a Hydrogen bomb in slow motion
But many billion times more powerful. And their "nuclear waste" was new elements.
But it would take years before scientists were able to confirm his theory by analyzing the light from stars
Each element emits light at a particular frequency when heated up.
Imagine a sodium street lamp - it emits light of a yellow colour specific to sodium
It's the same with stars.
Take our sun.
If you break the light down into a spectrum you can see lines like a barcode corresponding to the elements
Each element has specific colors helping scientists identify elements like hydrogen which emits mainly red light
In 1990 NASA launched the Hubble Space Telescope to unravel some of the mysteries of our early Universe
Lift off of the Space Shuttle Discovery with the Hubble Space Telescope, our window on the Universe
Hubble promised scientists unprecedented views of the young universe.
It would be able to look back through space and time
and examine early stars to discover if they were making new elements.
But the dream soon turned into the worst nightmare.
After it was launched they discovered that Hubble's mirror was distorted - it saw everything out of focus.
It needed corrective lenses.
And the only way to fix it was to send up another space shuttle.
One of the repairmen was astronaut Jeff Hoffman.
We were working with a two billion dollar telescope and the last thing we wanted was to break something,
and leave it worse off than when we got up there.
First the crew of the rescue mission had to capture the crippled telescope.
Then execute a repair mission unprecedented in the history of space flight.
First they had to open the access doors on the side of the telescope.
The one thing about working on Hubble that is very different from working on a car
is you look over your shoulder and there you are in space and the Earth is going by below you, the stars above you.
The astronauts had to carry out fine detailed work in the most difficult conditions.
When you're working in a space suit your hands are encumbered by thick, stiff gloves.
It's sort of like working in ski mittens - it was quite a challenge
All went well until Hoffman attempted to close the huge access doors.
I just had to close up the doors, and when I went to close them and that they wouldn't close properly,
The doors were somewhat warped
and it took a while for it to sink in - this was very serious.
If you can't get the doors closed you lose the telescope.
Using improvised tools Jeff and a colleague were finally able to close the doors.
It took the team five days to repair the stricken telescope.
Cosmologists around the world held their collective breath.
They waited to see if the most expensive telescope ever built would deliver what its designers originally promised
I well remember New Year's Eve, 1993, December 31st.
When my phone rang, and it was an old friend who worked at the Space Telescope Science Institute in Baltimore.
He said, 'Jeff you have any champagne left over from your party?'
I said, 'Yeah, we still have a half bottle in the refrigerator.'
He said, 'Well, crack it open again and drink a glass because we got the first picture back and Hubble works.'
This is what Hubble saw - the images were beyond anyone's wildest dreams
Hubble captured the final moments of a star's life when it explodes and blows off gas and dust.
It also captured interstellar nurseries of new born stars - exploding into life billions of years ago
And dark pillars of cosmic dust - millions and millions of miles long
- ready to spawn a new generation of stars and planets.
But Hubble's true moment of glory was still to come.
Over a ten day period in 1995 the mission controllers pointed the telescope at a distant empty patch of space.
What emerged was the Deep Field image - a tapestry of distant galaxies.
Hubble was looking back in time to some of the first galaxies and stars created.
it revealed thousands of galaxies that hadn't been seen before,
so the universe became, to our consciousness, far richer after the Hubble deep field,
It showed for the first time faint images of galaxies formed just a billion years after the big bang.
Scientists then examined the spectrum of light from these distant stars
and showed that these early galaxies had already created elements heavier than hydrogen and helium
Sir Fred Hoyle may have been wrong about the birth of the Universe but he was absolutely right about the stars
The early stars acted like giant thermonuclear reactors creating new elements
You can think of the creation of all the elements in this room in some sense, like a car assembly line,
because in a car assembly line, each part is sequentially added to the vehicle, until it's complete.
Fusion reactions inside these young stars released enormous amounts of energy and heat
which forced atoms to fuse to form new heavier elements one after the other
Three helium nuclei combined to form carbon
two carbon nuclei fused to form magnesium, magnesium to form neon
and so on over a period of hundreds of thousands of years until silicon fused to form iron.
Iron is a very special atom.
The protons and neutrons inside its nucleus are very tightly bound together
so that even the extreme temperatures inside the stars couldn't get it to fuse into heavier elements
It resolutely stays iron.
It was the end of the road - the production line of element building shut down
But our universe was still not complete
There were all the ingredients to make a glass of water
And some of the elements to build part of our convertible.
There were also quite a few of the ingredients to make a human being
the oxygen we breathe, the calcium in our bones¡ and the iron in our blood
But there still weren't any of the vital ingredients like chromium for our car fender
And some metals like Zinc that our bodies can't survive without
The universe was about to enter a super creative phase where it produces all the elements heavier than iron
To make the missing pieces in our birth of the universe jigsaw would take some of the most powerful explosions the universe has ever seen
Our Universe has already celebrated its 500 millionth birthday.
There are still another 13 billion more to go before humans appear on the face of the earth
Giant new stars have made many of the elements in the world we see around us.
But some vital elements are still missing
heavy metals like chromium and zinc, and expensive ones like gold and platinum
To finish the job, the universe conjures up the most amazing phenomena since the Big Bang
Massive exploding stars called 'supernovas'
When the giant stars that made the lighter elements ran out of fuel they collapsed in on themselves
creating incredible amounts of energy and enormous explosions
These explosions were so powerful they could fuse elements even heavier than iron and restart the element production line
Tony Mezzacappa from Oak Ridge National Laboratory in Tennessee
believes that without exploding stars life itself would not exist
Life as we know it certainly would not exist were it not for core collapse supernovae events
They are very clearly one of the key links in our chain of origin from the Big Bang to the present day
One of the most recent and biggest supernovas closest to our galaxy was seen in the southern hemisphere in 1987
When a supernova like 1987A explodes it emits light containing the signatures of the elements within it
By examining this spectrum of light scientists can calculate what elements are being forged inside the exploding star
Massive stars evolve to an onion-like configuration at the end of their lives.
They have an iron core and outside of the iron core are layers of successively lighter elements
Inside the iron core, the temperature rises to 8 billion degrees, nearly 300 times hotter than the center of the sun
It is so hot the iron atoms that have sunk to the stars core are torn apart. The core destabilises
The cores then collapse on themselves in a fraction of a second, the collapse proceeds to very, very high densities
The core collapses at speeds of more than 43,000 miles per second.
A volume the size of the earth crunches down nearly 6 times the size of Manhattan in an instant
The core becomes super dense.
If one were to take one cubic centimetre of that matter, that would be the size of a sugar cube
that sugar cube would be so dense that it would weigh as much as the entire human race
The core rebounds, like a compressed rubber ball - and launches a massive shock wave.
The shock wave hurtles out, smashing through the different skins of the star
As it punches through the outer layers of the star, the energy generated restarts the element production line
Atoms are smashed together to make brand new heavier elements - all heavier than iron
Then the star explodes and the shock wave pushes the shrapnel like debris outwards - further and further into space
In a very real sense our lives depend on the stars in the Universe, without their lives and deaths, we would not be here today
These astonishing images taken by the Hubble Space Telescope show the aftermath of these giant explosions
Nebulae - giant clouds of debris thrown off by exploding stars.
Swirling inside are big new atoms - gold, silver, zinc and lead
Without supernovas, our world would be a very dull place - and possibly lifeless
So I'm sure that, that Paris Hilton doesn't wake up every day, thinking about this fact
But really, if it weren't for exploding stars, those 200 million stars that exploded so we could be here today,
she wouldn't have anything to wear
So if it weren't for those supernova explosions, there wouldn't be any bling
Nine billion years after the Big Bang and all the ingredients are in place for life as we know it
The universe has grown up into a vast, complex place made up of billions of galaxies and uncountable stars.
In a quiet corner of the Milky Way, a mass of dust and gas begins to accumulate
It's full of the rich debris left over from one of the massive supernovae
and when it reaches a critical mass it begins to burn brightly
a star is born - our own star, the Sun
What's left over forms a disc of swirling debris in orbit around the new star
The gas and dust that make up this ring collide, pulled together by gravity.
The clumps of dust and gas become bigger and bigger.
Planets form¡ One of these planets is our earth.
Over the next 500 million years our planet slowly generates a protective canopy of gas - the atmosphere.
The first life appears. Just single cells at first
but as the aeons pass those tiny single cells evolve into plants and animals - and eventually humans.
We tend to disassociate ourselves from the universe, but that of course is completely wrong,
we are a vital part of the cosmos,
and so when we talk about the origin and evolution of the universe,
we're actually talking about the origin and evolution of ourselves.
Everything we can see on our planet was either made in the Big Bang or inside a star
Scientists like Krauss believe they now know the genesis of every atom that has created the world we live in
These atoms have been around since the dawn of time,
and when I was young my mother used to tell me, don't touch that, you don't know where it's been,
and she would have been amazed.
But this is not the final chapter in the story.
After almost 14 billion years the universe has really only just gotten started
Now we take a journey into the future to see how it all ends.
The universe we live in is nearly 14 billion years old
It has created the raw materials for everything we see around us.
The stars, the planets, trees, cities - automobiles - even us.
Our world is complete. But the universe is still evolving.
Scientists have come up with many theories on how it will end.
We know our universe began in a Big Bang.
What we don't know yet is what the future of our universe is going to be
Our universe may end with a bang or whimper, or something even more exotic.
One theory suggests that our universe will run out of steam and stop expanding
every star, galaxy and planet, every atom will start to collapse
ending in a single super dense pinpoint - known as the 'big crunch'
To find out if the Universe really is going to crash back in on itself
scientists first need to discover if it's still expanding or if it's slowing down
Astrophysicist Saul Perlmutter studies the death of the universe by finding beacons in space
exploding stars called type 1A supernovas
If you have enough of these exploding stars, these supernovae, that you've measured their brightness,
so the ones that look fainter and fainter and fainter must be further and further and further away.
And so you have some supernovae that little bit brighter, they're more nearby, some that are a little bit fainter
so they're a little bit further, and some that are very faint, so they're very far away.
Type 1A Supernovas are similar to the supernovas that created the heavy elements.
They differ in one important fashion - they always explode with the same exact brightness
This is because they are created in the same way
Two stars circle each other held together by their gravitational attraction
One is shrivelled and super dense glowing with white heat: a White Dwarf.
The other star has bloated to an enormous size
it's a red giant that is burning the last of its fuel
As the two stars orbit each other, the White Dwarf sucks gas from its companion and begins to grow year after year
When it is precisely 1.44 times the mass of our sun,
the White Dwarf crumples, collapses then explodes releasing a blinding burst of energy
Every Type 1A supernova explodes at the same 'tipping point'
and so are equally bright and visible across the vast distances of the universe
Perlmutter needs to find hundreds of Type 1A supernovae and then measure how fast they are moving away from us
By comparing the positions and dates of all these supernovas stretched over space and time
Perlmutter can calculate whether the universe is slowing down
His results are a shock.
The expansion of the universe isn't slowing down at all.
When we began the project of course the goal was to find out how much the Universe was slowing down
Now when we actually started looking for data it looked like the Universe wasn't slowing enough to come to a halt,
and in fact it wasn't slowing very much at all
and in fact when we finished the analysis it looked like it wasn't slowing, period, it was actually speeding up in its expansion
Perlmutter's astounding discovery means that the universe will not grind to a halt,
then crunch back down into a pinhead of super dense matter.
Quite the opposite - it will continue to expand faster and faster
Our Universe is literally flying apart.
The expansion of the universe will accelerate at ever faster and faster rates
Until literally, everything will get ripped apart,
not just galaxies, but eventually, matter, the earth, all the objects, stars,
the earth, planets, people, atoms, in a finite time, will get ripped apart.
Long after our Sun has burned out; 100 billion years in the future galaxies will pull apart.
The universe will be made up of isolated stars, which are running out of energy.
Some will become white or brown dwarfs - others will collapse into neutron stars or black holes
Then thousands of trillions of years after the Big Bang, even the black holes will evaporate
and all matter will decay to its basic ingredients Atoms will fall apart.
And even protons - the building blocks of atoms - will decay.
The most likely future is perhaps the most dismal one, where the universe becomes cold and dark and empty.
As the universe continues to expand and the galaxies speed apart from each other
- space will become empty and dead.
Our own cluster of galaxies, will be moving away from us faster than the speed of light, and will disappear from the night sky.
Eventually everything will just sort of wind down, and that's the end of things
Finally the universe will die and all that will be left is a cold dark and lifeless space