Universe: Beyond the Millennium - Stars

in five billion years our nearest star the Sun will die swelling and becoming a red giant the heat will be so intense if the oceans will boil our planet will be scorched beyond recognition the crust will melt the surface will become an ocean of molten rock all our universe is alive with the shimmering of countless stars but our vision from beneath the Earth's protective atmosphere shields us from the real dangers these are the most violent objects in the universe Bob Kirchner is a Harvard professor with a passion for the Stars he spent a lifetime studying them from their cradle to their grave I remember as a kid going out and seeing stars at night and I lie on the snow flashlight and a star map and try to dope out what things were where on the sky and my mother used to call out the back door she said Bobby come in get off that snow today instead of lying in the snow Kirchner comes to Kitt Peak Observatory can peak is at about seven thousand feet so it's not a particularly high mountain but it is considerably above the valley floor so it's a good site for astronomy also the weather is very good down here in Arizona so we get a lot of clear nights he has a date with the night sky to look for one of the most dramatic and beautiful events in the universe the birth of a new star as the Sun sets over the Arizona desert the observatory is open for work this mountaintop gives astronomers an unrivaled view of the sky high above the clouds and obscuring lower atmosphere Kershner is looking for giant clouds of gas inside our galaxy Milky Way that may give birth to new stars okay ready let's go to the first one all right there are catalogues of regions where stars have been forming or where there are big clouds of gas that people have compiled over the years and so by looking at some of these things from the catalog we can begin to investigate individual areas where there really are stars forming and where we look deep into them to see what's going on with their high-powered telescopes Kirchner and his colleagues have been peering into enormous gas clouds inside our own galaxy this is the Lagoon Nebula an interstellar nursery which is giving birth to hundreds of new stars the clouds are mostly made of hydrogen the most abundant element in the universe they are so dense they begin spiraling inwards under their own gravity the matter collects and begins to form a fledgling star a protostar with a disk of gas and dust falling inwards it spins faster and faster this was probably how our Sun and the solar system was born after a while the material that is in orbit around the protostar starts bumping into itself and so it builds up bigger particles out of smaller ones eventually makes dust and makes gravel and then very quickly probably builds up things as big as planets this is the moment of birth of a new star with a new Sun spawning a disc of orbiting planets the star shrinks down more and more until it becomes hot enough and dense enough for the nuclear reactions in the center to get going that turn it from being a glowing ball of gas into a real star something that has a nuclear fire down in the center the same nuclear reactions that take place in a hydrogen bomb converting hydrogen into helium produces the energy that causes stars to shine when the nuclear fires ignite a new star is born since the birth of our solar system the closest and most familiar star of all our South has bathed our planet in heat and light at the heart of the Sun 600 million tons of hydrogen are converted into helium every second in a nuclear reaction that fired up four and a half billion years ago for generations the only way astronomers can study the sun's fiery atmosphere was during a total solar eclipse for a few fleeting minutes the Sun drops its guard allowing us a glimpse of its awesome power francisco diego a professional eclipse chaser saw his first eclipse as a teenager in mexico it began a lifelong fascination with the son the total solar eclipse is an event that when you see it you will never forget the day of the Eclipse is very special when you look at the Sun you see this beautiful complete perfect disc but the day of the Eclipse exactly at the time that has been predicted for many many years in advance you see how the moon starts eating into it at total eclipse the moon will align itself perfectly between the Sun and the earth the moon is 400 times closer to the earth than the Sun and by extraordinary cosmological coincidence it's also exactly 400 times smaller Diego and his Astronomical colleagues will travel anywhere on earth to study this rare celestial event each eclipse will last just a few precious minutes the temperature starts dropping and it drops to about ten or fifteen degrees in some places is very noticeable you feel this wind this atmosphere just agitating and it is very very tense moment then you look at the West because the shadow of the moon is coming towards you very fast on at 3000 kilometers per hour the landscape loses its colors a hundred mile wide Shanna will pass over the surface of the earth the brightness of the midday Sun will slowly turn tonight the sky gets so dark that the corona which is very faint is now visible it really flourishes is like a flower a white flower that opens its petals in the sky this is the sun's corona a glowing atmosphere normally obscured by the intense glare it burns at over a million degrees giant prominences erupt from its surface they could swallow the earth dozens of times over like giant fingers they stretch for millions of miles into the vacuum of space but for solar astronomers like Diego the total eclipse is over all too soon after just a few minutes the alignment is lost Suns brilliant light bursts out from behind the moon a magical sight that eclipses watchers have named the diamond ring when you finish looking at the diamond ring and you see the shadow of the moon rushing away from you now towards the east then you see that was it those two or three minutes are gone you have been waiting for that for years and suddenly it is gone you feel like a vacuum and you say this is not enough I want more as the Sun breaks out from behind the moon once again the earth is bathed in its light we rely on the sun's constant energy to breathe life into our planet it gives us free energy its heat evaporates water to produce the clouds and rain the slightest change in its behavior could put the world and even the human race at risk to keep a constant vigil on the sun's enormous power from above the Earth's shimmering atmosphere a new satellite Soho was designed and built by NASA and the European Space Agency launched in 1995 Soho was to promise a breakthrough in son observations and give astronomers a front-row view of our nearest star Douglas Gough a solar astronomer at Cambridge University was one of the members of the Soho team the satellite has gone to a position between the Earth and the Sun where the gravitational pull of the two cancels so it sits there looking at the Sun continuously and beaming back the information to earth the images it beamed back were beyond their wildest dreams the sun's raging surface is a turbulent world its eruptions ripped and torn by enormous magnetic fields so who revealed that like the earth the Sun has weather gigantic solar tornadoes twist through its atmosphere and gigantic shockwaves will rip across its surface the surface of the Sun is heaving every five minutes the entire star breathes in and out our Sun is pulsating this is the real sound of it vibrating speed it up thousands of times the outside of the Sun is in this very dynamical turbulent motion just like the turbulence behind the back of a jet engine the jet engine creates a lot of noise similarly this this motion creates a lot of noise inside the Sun which reverberates around and makes the Sun sing and by listening to those tones we can learn about the structure of the Sun inside below its churning surface there's a nuclear furnace that will burn for billions of years from its nuclear heart trillions and trillions of tiny particles of radiation photons make their arduous journey from the core to the surface the photons collide with super-dense gas they take so many hits that a trip that should take just a few seconds takes millions of years but after the photons escape from the surfaces light they take only eight and a third minutes to travel from the Sun to the earth every summer millions of people go out of their way to worship their local star even 93 million miles away we can feel the sun's enormous destructive power but not all of us are naturally protected against the sun's lethal rays fair-skinned people have weak defenses the result is sunburn from the sun's deadly ultraviolet radiation this anti burn patrol is on the lookout for unprotected babies the greater the exposure to the Sun the greater the risk of getting skin cancer especially deadly malignant melanomas even greater dangers are whipped up when the Sun surface is twisted and contorted by powerful magnetic fields these fields can puncture the surface and create dark areas called sunspots each one is big enough to swallow the entire earth and their presence is a warning the magnetic disturbances caused enormous eruptions blasting huge amounts of radiation billions of tons of charged particles into space every 11 years the sunspots increase in number and size a mass of intense energy can head our way engulfing the entire earth when this happens is not just the sunbathers who need to head for cover March 1989 the Sun was about to give eastern Canada an early wake-up call it was the height of the sun's 11-year cycle the solar maximum out in space a cloud of incandescent matter over 1 million miles long was heading straight for Earth night workers at the National Grid Control Center had no idea what was in store at 1/4 3:00 in the morning engineers noticed an enormous surge in their power system when the cloud hit the earth it induced a massive surge of electricity inside the power cables engineers struggled to reduce the load but in a matter of minutes they'd lost control of the whole system power plants over half a million square miles of Quebec were swamped with excess current moments later the whole grid blew the city was plummeted into darkness power was lost to 8 million homes further north the same cloud that had plunged Quebec into darkness was lighting up the night sky in a massive celestial fireworks display this is the aurora borealis some of the particles from the cloud had become trapped inside the Earth's magnetic field as they passed through the atmosphere they reacted with the air like a giant neon light the solar radiation lit up the night sky you our son is not the only star that threatens our existence space is filled with harmful particles and radiation traveling above the Earth's protective atmosphere is extremely dangerous despite the dangers of traveling above the atmosphere our desire to conquer space is so great that we are prepared to risk the consequences in 1969 Buzz Aldrin Neil Armstrong and Mike Collins began their historic quarter of a million mile journey to the moon I'm talking to you by telephone from the Oval room at the White House and this certainly has to be the most historic telephone call ever made celebrations ran high as Aldrin and Armstrong stepped onto the lunar surface for the first time but behind the euphoria the pair were keeping a secret from Mission Control in Houston they'd seen more than just the dust of the moon's surface it was only when they returned to Earth that Armstrong and Aldrin revealed their secret they reported seeing strange white streaks of light flashing in their eyes NASA decided to run tests on future missions to discover exactly what the light flashes might be astronaut Charlie Duke was their guinea pig on board Apollo 16 he was asked to watch out for the mysterious flashes we're on our way to the moon and all of a sudden I close my eyes and someone it was like a the first one was like a flash bub exploding inside your eye it was very bright very white and I said hey I saw my first one it was just a streak of light very fast and and just as white as it could be in very bright a young researcher Larry Pinsky was assigned to work with Duke and find out what was causing the flashes he recorded Dukes comments back in Houston and eventually realized the flashes could only be one thing well it turns out that they were seeing cosmic rays they were seeing these elementary particles that permeates space that penetrate the spacecraft actually penetrate the body in this case penetrate the odd what Pinsky had worked out was the Duke and the other astronauts were seeing high-energy particles produced from one of the universe's most violent acts of destruction when a massive star trillions of miles away explodes as a supernova as a heavyweight star nears the end of its life it incinerates all the few minutes call heavier a star is the more catastrophic its death the core becomes unstable it loses energy and starts a headlong collapse that for one second gives off as much energy as all the stars in all the galaxies in the universe cosmic rays are actually particles they're actually little pieces of matter they are the nuclei of atoms the atoms come from supernovae and they're just the bare nucleus accelerated to very very high velocities I'm sure they were there all the time but the only time you'd ever notice them is when you sort of got quiet close your eyes and thought about it and then you can see them going off there wasn't any pain associated with it it's just sort of like a very spectacular fireworks display going off inside your eyeball when the astronauts returned to earth Pinsky took a closer look at Dukes space helmet he found hundreds of microscopic tracks where the cosmic rays had tunneled right through they are tremendously penetrating and do considerable damage to the molecular structure of whatever they pass through and this is the reason why their hazard to people when they pass through you the thought occurred to me you know if I was out here maybe a couple of years these little thing burning a hole through my my head might cause me some problems in the future but we didn't worry about it of course on a short mission like we were on but if a supernova is too close it won't be only astronauts who will be at risk it could kill everything down here on earth our galaxy is packed with over a hundred billion stars many of them near the end of their natural life at least one or two supernovas explode in our galaxy every century two young astronomers from Caltech have now come up with a new theory of life on Earth that has shaken our scientific beliefs a theory that links the death of stars to mass extinctions on earth the fossil record of the last 500 million years shows five or six huge extinction events in which anywhere from sixty to ninety five percent of species on earth dinosaurs reptiles etc were wiped out and so what got him and I really set out to do was to come up with some sort of model that would explain why the major extinctions happen when they do buried glitch and gout and visage have calculated exactly when the earth may have been close to ancient supernovas the key to their model was understanding the rotation of the Milky Way like a giant spinning wheel the Milky Way is circled by spiral arms packed with billions of stars alarms they're really disturbances that sweep through the disk of the galaxy and gas and dust tends to accumulate along these disturbances if you imagine looking at our galaxy face on the spiral arms appear like swirls going out from the center to the outer edge rather like the kind of whirlpool you see when water goes down a drain the spiral arms aware and supernovas are most likely to explode our solar system passes in and out of the arms once every 15 million years we know the location of the spiral arms fairly well so we could trace the orbit of the earth back into time the help was to find a link between the times of occurrences the extinctions and the timing of the passage of the earth through the spiral arms their calculations revealed that the biggest mass extinctions correspond exactly with the dates when the earth had passed through the spiral arms if a supernova exploded nearby the surface of the earth would have been swamped by deadly radiation if the solar system happens to be passing through a spiral arm your chances of encountering a supernova explosion at close enough range to do serious damage to the earth are quite high in fact we estimated something like 50/50 understanding the mystery of just how massive stars die has taken astronomers centuries to unravel modern astronomers picked up their first cruise from an unusual source during the second world war in occupied Holland yondu vandaag a scholar of ancient chinese manuscripts discovered a document written in china nearly 900 years earlier it reported on the 22nd day of the seventh month of the first year of period chill we said frustrating myself I have observed of appearance of a guest star in the fifth moon in the eastern heavens in Taurus it was visible by day like Venus 20 rape shut out from it on all sides the account told of a bright star that had appeared in the heavens in the summer of 1054 which shown for 22 months and then disappeared duvan de realized the significance of his discovery through contacts in the Dutch underground he smuggled a paper through enemy lines and across the Atlantic to astronomers in the United States 20 years earlier American astronomers had discovered that a distant cloud of gas called the Crab Nebula at the fringes of our galaxy was expanding by working backwards they had calculated that had originated from a single point some nine hundred years earlier exactly the time of the Chinese star astronomers believed that the Crab Nebula was the debris from an exploding star a supernova but at the time they had no proof the Chinese star was so bright it could be seen in daylight and for a time it was even possible to write by it's light what's more the star had appeared in exactly the same part of the sky as the Crab Nebula it clinched the argument it had to be the remains of an exploding star the blue glow of the Crab Nebula comes from escaping cosmic rays the colored pincers are the remnants spewed out in the giant explosion but for this star the supernova explosion wasn't the end left behind was a strange corpse professor Antony Hewish from Cambridge University discovered there was life beyond the grave for dead stars when he built an unusual telescope in the 1960s we started building in 1965 the thing was we wanted a large radio telescope which was very sensitive but it had to be rather cheap and I decided on this construction of diavik dipole array we all took our turns in hammering the posts into the ground and hanging up the wires and putting into the cables it was just very much a team effort over the next two years Hewish and a small team of students built a jumble of wires and poles spread over a four acre site this strange-looking telescope was to discover the weirdest object in the universe and when Hewish the Nobel Prize the task of running it was the responsibility of them research student Jocelyn Bell that was producing miles of chalk paper 96 feet of chart paper every day and we kept scanning the sky over and over and over again I ran it for six months and generated several miles of chart paper in August 1967 after just one month of operation an unusual signal caught her eye as the pen ran over the chart paper went beep beep beep beep beep regular pulses about one and a 1/3 seconds apart looks so artificial it looks like an intelligent signal to begin with and intentional intelligent signals coming from from outer space what are they well you make a joke and say perhaps somebody's talking to us in some kind of a code so we call these things little green men LGM I mean we didn't really believe it on the other hand it was a possibility you couldn't immediately ignore after months of analysis Hewish and Bell came to an outstanding conclusion only a small super dent spinning object could be creating such a fast pulse the only possibility was the collapsed core of a supernova a neutron star here was the living corpse I really didn't know neutron stars existed until I started talking to people and said look can you tell me any sort of starlets but smaller than a thousand kilometers and up came the answer neutron stars and maybe receive the first one okay the pulsus that come from one of these neutron stars come to us because like a lighthouse these stars are spinning and they have a beam that's focused by the magnetic field of the star and every time the beam sweeps across us across our radio telescope we pick up a pulse but for one year there are literally hundreds of theories being published and it was an absolutely open question and I think it only became generally accepted after about 12 months that it that it had to be in the Transpo the revelation triggered a wave of activity radio telescopes all over the world scan the heavens looking for the mysterious pulses less than a year later the giant Arecibo dish in puerto rico picked up a signal it was coming from the heart of the Crab Nebula they had found the ticking corpse at the center of the Chinese supernova the spinning neutron star was not only giving off radio waves amazingly it was also visible high-speed television pictures revealed it was flashing on and off 30 times a second it was the most powerful object that anyone had ever photographed neutron stars are like nothing else in the universe they're so dense a thimbleful would weigh over a hundred million tons it supposing you somehow managed to land on a neutron star then you are experiencing phenomenal gravity and the atmosphere instead of being 5 miles thick is about five millimeters thick so if you stood on the neutron star the atmosphere would be sloshing around between your doors but even a neutron stars phenomenal gravity is surpassed when a real super heavyweight star dies when a star a hundred times heavier than our Sun switches off it curls with a bang while we see the outward explosion as a supernova this masks the inward implosion the core is collapsing into the most dangerous object in the universe the density becomes so great in the center that gravity sucks in time and space itself from the outside universe the darkness forms at the heart of the collapsing star a black hole is born if you have a massive star once the massive star has exhausted its nuclear fuel which is keeping it hot and keeping it puffed up gravity become so strong that it just overwhelms all pressure the material can provide and the star goes imploding inward you know and it's gone forming a black hole everyone has heard of black holes no one has seen them or being near one at the center of the black hole is a point called singularity everything that has ever fallen into a black hole is destroyed crushed into a pinpoint of infinite density and infinite smallness even space and time are squelched out of existence the singularity is a place where gravity is essentially infinitely strong it's a place where matter gets destroyed it's a place where space and time as we know them get destroyed at some time on the future a spaceship from Earth will be sent into the jaws of the most elusive object in the universe the spacecraft traveling towards a black hole wouldn't see the singularity hidden deep inside it would only see the blackness around it it's target as a gravitational pull that is so great not even light can escape as the spaceship goes flying into the core of the black hole I begin to feel my self being pulled from head to foot and squeezed from the sides my body gives way I die the atoms of which I may give way and all is destroyed in the singularity all that remains is a perfect sphere of absolute darkness a gravitational ghost of the star that died the perils of a black hole are thankfully remote even the nearest is over five thousand light-years from Earth our nemesis lies much closer to home like every star in the galaxy our son has a finite lifespan one day it will run out of fuel and scorch the planets it's a terrible fate that astronomers have known for decades we expect that the Sun will swell up in about five billion years and it will become a red giant star that's the beginning of the end for the Sun in five billion years our local star will have exhausted its fuel supply without fuel the Sun will in its death throes the star that gave birth to life will swell and engulf the earth and nothing will survive the amount of energy we get from the Sun would increase tremendously as earth would heat up oceans would boil eventually the mountains would melt and evaporate the earth would be incinerated by our own friendly star the Sun the heat from this red giant will be so intense the earth will be scorched beyond recognition the Earth's crust will melt the surface will become Aleutian rock nothing will survive the ultimate catastrophe and that's the end of the story for the Sun it will cool off and as time passes the Sun will become a dimmer and dimmer cooler and cooler Klinker of a leftover star the earth devoid of all life will sit in the cold emptiness of space as our sons brilliance dies somewhere in the galaxy in an endless cycle of life and death a new star will be born maybe it will spawn its own solar system even a new planet like Earth and a new place where life can flourish you

Channel: Naked Science

Views: 440,834

Rating: 4.5691133 out of 5

Keywords: universe, beyond, millennium, stars, astonomy, documentary, star, research, space, thory, kitt, peak, national, observatory, night, sky, birth, form, gas, cloud, astronomer, robert, kirshner, harvard, university, professor, protostar, spacecraft, mission, supernova, neutron, orbit, particle, dust, spaceship, eclipse, chaser, nasa, esa, european, galaxy, agency, images, magnetic, kip, thorne, physicist, pulsating, sun, solar, aurora, borealis, northern, lights, singularity, energy, mass, extinction, spiral, arm, milky, way, black, hole, sphere

Id: Hm0tgI2xgPE

Length: 50min 19sec (3019 seconds)

Published: Thu Apr 17 2014

Reddit Comments

[u/fnlwyrup]

Seriously though, this would be a great reddit to have the year of production included in the title.