Corrupt Stars

the universe is quite literally teeming with stars there are trillions upon trillions of them out there and they illuminate our sky as tiny spots of light atop the darkness of space these are the stars that we can see every day stars which have entered and exited the main stages of their life powered by fusion and nuclear physics this stellar life cycle is constantly playing out all over the universe but not everywhere we exist at a time when the universe has recycled and evolved most of its matter many times over leading to heavier elements stabler stars and more metals but these stars are not the only types out there there are predicted to be dozens of other types out there which we have yet to observe the stars which we can't see these are known as hypothetical stars and the list is even longer than the list of the stars we know today stars which existed in the early universe styles that are hidden by their size and composition stars which have been corrupted after death tainted by gravity and radiation whose properties pushed the limits of possibility in the known universe but before we dive in to take a look at the ones that could be lurking in our universe today we first have to go backwards back to near the beginning of time to find out where it all began in the early universe the temperature was far too hot for stars and even when it finally did cool down it remained dark for hundreds of millions of years but all the while hydrogen and helium atoms were gathering in the darkness into huge clouds that began to lay the foundations for the first galaxies these massive gas clouds were the perfect incubators for the first stars to emerge known as population 3 stars these were stars that existed over 13 billion years ago composed of the universe's primordial gas hydrogen helium and a tiny bit of lithium they were made from matter directly from the big bang before any of it was recycled into heavier elements by cosmic processes if nothing else these would have made them enormous at least 10 times the mass of the sun and usually hundreds or even thousands of times its diameter this also made them incredibly inefficient as they burn through their fuel much more quickly as a star undergoes fusion elements like carbon and oxygen can keep stars like the sun cool enough that they don't continue expanding whereas population 3 stars lack these elements and so radiated hydrogen causing them to balloon to what would be considered supergiant and hypergiant sizes in the milky way today because they were so volatile and unstable they probably lived very short lives lasting only a million years or so before they blew up in the first cataclysmic supernovae these explosions released the metals fused in the cause of these stars and distributed them into the surrounding space creating richer gas clouds from which more stable stars with higher metallicities could form the reason they are classed as population 3 stars is because of the order they were classified in population 3 stars were first predicted in the mid 20th century and ever since we have long struggled to obtain proof of their existence given their brief life spans it is very unlikely that any exists today and the distant galaxies in which we might be able to see them due to their light delay are so far away that they are much too dim and diffuse to the point that it is virtually impossible to analyze their stellar population on an individual basis but with that said there is one candidate cr7 not the footballer this is actually a galaxy although the galaxy's name was in fact inspired by the portuguese footballer but in this case it stands for cosmos redshift 7 and is one of the oldest and most distant galaxies ever discovered cr7 was discovered in 2016 during a survey of distant galaxies which emit lyman alpha radiation from hydrogen with a light travel time of around 12.9 billion years is possible that this galaxy could contain a portion of early population 3 stars not only is cr7 about three times brighter than the other galaxies as similar depths but scientists have suggested that the emission lines detected from this primordial galaxy are consistent with a wave of population 3 stars in one area this is an artist's impression of what that might look like were we able to see it up close it's crazy to think that the ancient light which we are detecting from this galaxy now could have come from pristine mata fresh from the big bang almost as old as the universe itself [Music] stars were considerably bigger back then dwarfing all but the largest stars in our galaxy today and some speculate that this size and mass could have created something truly remarkable enter the quasi-star this is another hypothetical style which could only have existed in the early universe when gas was untainted by heavier elements and stars were able to grow much larger unlike normal stars the energy output from a quasi-star is generated not by nuclear fusion but from a black hole at the center of the star this sounds crazy i know but it might just have been possible in the largest of stars at nearly the beginning of time most stellar black holes form through supernovae and these explosions are so violent that they usually disperse the outer layers of the star into a nebula and the black hole forms within but in the early universe hypermassive protostars could have been forming inside the enormous gas clouds which were forming the first galaxies some of these proto-stars could have accumulated so much gas that fusion was no longer able to suppress the might of gravity and the star would have gone supernova however because these proto-stars would have been so huge it is possible that the star's outer layers could have withstood and absorbed the shock of the supernova leaving the star's structure intact while its core collapses into a black hole thus some people refer to these as black hole stars [Music] once formed the black hole would immediately begin pulling in mata but not as fast as you might expect while black holes pull a lot inwards they also radiate a lot of energy outwards as the material they shred up falls into orbit around its event horizon at high speeds this would have created more than enough energy to not only preserve the quasi-star's structure but also to radiate as much light as a small galaxy therefore you can think of quasi-stars as stellar quasars in order for this to occur a star at least a thousand times the mass of the sun would have been required which is more than three times as heavy as the largest star known today it would also have required the diameter of the star to be over 10 billion kilometers which if placed at the center of our solar system would extend as far out as to consume all eight of the planets in our backyard so these stars might have been able to exist but probably not for very long the black hole would quickly grow larger and accumulate mass and would expand eventually consuming the star altogether after a few million years because these black holes would have formed so early on in the universe it has been proposed that quasi-stars might have been one of the sources of the largest supermassive black holes at the center of large galaxies that we see today perhaps even the milky way's own black hole sagittarius a because stars are much smaller these days black hole stars cannot exist in the universe right now but they might be able to exist with a neutron star at their core neutron stars are formed when massive stars go supernova but what remains is not massive enough to form a black hole that collapses down into a body the size of a city with unthinkable density pressure and gravity and it's possible that one of these could override the heart of a giant star this brings us to the thorn jikkov object a red giant or supergiant star whose core has been replaced by a neutron star essentially a dead star inside a live one unlike the quasi-star a thorne jacob object could form in a binary star system or a densely crowded globular cluster a nearby or neighbouring neutron star might fall into the giant star via its trajectory or a star could end the main sequence of its life and become a red giant expanding to hundreds of times its current diameter possibly engulfing the neutron star within its outer layers once inside the star the neutron star begins moving towards the core like a virus while neutron stars have incredible magnetic fields which could dissolve every human on earth from the distance of the moon a supergiant star is so enormous compared to the city-sized neutron star that it can actually travel pretty far before it starts to disturb the star's structure over the space of a few hundred years the neutron star will spiral inwards towards the core pulling the core into a binary orbit with it and eventually the two will merge at the center if the combined mass of the two exceeds between four or five times the mass of our sun then the pair will collapse to form a black hole which will quickly gobble up the star however if the combined mass is below this four or five solar mass limit then the two will merge into a single neutron star which sits at the center as a kind of dead surrogate heart for the giant this would have a profound effect on the internal structure of the star the surface of a neutron star is several orders of magnitude hotter than the cause of most giant stars and the neutron star's rapid rotation would create an envelope of accreting supercompressed gas around the corrupted core weighing about 30 times the mass of the sun this process creates uncharacteristic amounts of lithium molybdenum and rubidium in the star which we can detect as it is expelled to the surface as such there are a few candidates which have been identified by their apparent excess of these elements the problem is it's hard to identify these stars as they would appear much the same as a red giant with the outer layers concealing the chaos that is erupting below they also probably don't hang around for very long perhaps between 1 or 10 million years meaning we would have to exist at a certain chance point in time to observe what is probably quite a rare phenomenon if correct it's easy to think of neutron stars as a single type of object however there are a few subcategories of neutron stars based on their characteristics and behavior the classic example of this is the magnetar you might have heard of one of these it's a neutron star which is rotating so fast that its magnetic field is amplified making it much more corrosive and irradiating to its surrounding space well there are loads of other hypothetical types of neutron stars most of which are thought to occur when the line between a neutron star and a black hole is blurred the hypothetical q star is one such type of boundary object it is a massive dense and compact neutron star which lacks sufficient mass to collapse into a black hole but the gravity is so strong and intense that it consumes most of the light around it kind of like an op neutron star combined with a premature black hole thus is also known as a grey hull because such little light would escape from one of these ultra dense bodies they would have a very low visibility and could easily be mistaken for small stellar black holes but what sets the q-star apart from an ordinary neutron star is that under conditions this extreme matter is in what is known as an exotic state with exotic physical properties found nowhere else in the universe not classifiable as a solid liquid gas or plasma up until this point all the stars discussed have been composed of normal matter and atoms which can be in various states based upon their energy levels in a plasma state the fourth state of matter atoms become so energized that the matter starts behaving as one but an exotic state of matter takes this a step further in a neutron star the pressure is so strong that these atoms are crushed into subatomic particles mainly neutrons exotic matter is their next level down the compression is intense enough to break the neutrons up into their constituent subatomic components namely quarks which themselves begin behaving as a single unified plasma-like substance quarks are the building blocks of subatomic particles and they are as low down into the tiny pieces of nature as you can get an abundance of free quarks under intense conditions would create stable quark matter free quarks are not usually found alone in the rest of the universe and so at this level of cosmic granularity the mata likely has properties that violate the laws of physics as we experience them for example particles with a negative mass which zip off in the opposite direction when force is applied as such exotic stars make up another subgroup of hypothetical stars an exotic star is one composed of something other than atoms or subatomic particles like protons neutrons electrons and muons exotic stars are composed to varying degrees of free quarks the problem is it's very difficult to do research on quarks to learn how they behave as the temperatures and pressures required to create free quarks can simply not be recreated in a lab and so we are only able to make predictions and search for observational evidence but many of these types of exotic stars are thought to look like ordinary neutron stars say for a few slight differences of these types the quark star is probably the most likely the quark star is another hypothetical intermediate stage between a black hole and a neutron star these are thought to occur when a massive neutron star eventually attracts so much mass through accretion that it can no longer keep its neutrons apart as the neutrons dissolve into three quarks it collapses further into a comparatively smaller object about 16 kilometers in diameter when compared with the standard 25 kilometers in diameter for a neutron star recent research has suggested that free quarks do not arise inside the cause of neutron stars which would probably mean that quark stars are their own type of phenomenon and not just a particularly dense or massive neutron star this would mean that a quark star would be composed almost entirely of quark mata with a thin but dense exterior shell if this is the case then they would quickly dissolve and have short life spans with their shells analogous to a neutron stars it would be difficult to distinguish between the two in fact a quark star might be harder to detect than a neutron star because its gravity would be so intense that less light would escape into space which could make quark stars much less radio loud or even radio silent one of the handful of tentative candidates we have for a quark star is psr b0943 plus 10 which was the first pulsar ever to be discovered by soviet astronomers in 1968. in 2006 a team of researchers at peking university in beijing proposed that this pulsar might in fact be a low-mass quark star due to its smaller than average polar cap and some other variances from conventional pulsars in the decade and a half since however we've never really gotten much closer to ascertaining the truth and the quark star remains just a theory like many other hypothetical stars quark stars probably don't have very long life spans so what becomes of them when it reaches the end of its time well one possibility is that it may become an electro weak star a tiny hand-sized ultra-dense star once the quark star becomes too massive through accretion the quark degeneracy pressure which keeps free quarks apart from one another is overcome by gravity causing the body to collapse even further to a level that is so extreme that the laws of nature start melting into one another the star collapses to a body about the size of an orange yet it contains more than double the mass of the earth at this density the environment within the star becomes analogous to the very early universe where the temperatures were so high that the fundamental nuclear electromagnetic and gravitational forces we experienced today were merged together as one in an electro weak star the interior is under so much pressure that electromagnetic interactions and weak nuclear interactions merge creating the electro weak force this colossal composite force would then squash the free quarks into one another converting them to leptons leptons are a much lighter kind of elementary particle and so this mass is dispersed via radiation pressure which releases the energy in the form of neutrinos this electro weak burning keeps the remnant of the quark star from collapsing completely so much so that these speculated microstars could live for as long as 10 million years as it gradually burns through all of its quarks as of the making of this video however there are no electro weak star candidates but perhaps as our technology to detect neutrino patterns improves we may have a better chance there are six types of quark but for the purposes of this video we only need to consider the three lightest types up quarks down quarks and strange quarks up and down quarks help us to build protons and neutrons and thus the nucleus of an atom other types of quark would quickly decay elsewhere in the universe but inside the cause of quark stars the story is different if the pressure inside a quark star is strong enough then up and down free quarks would be squeezed together to create strange quarks strange quarks are the heaviest and thus most influential of the three types discussed and thus have extreme properties strange quark matter is by far the most dense material in the known universe and is so corrosive that it turns everything it comes into contact with into strange quark matter as it dissolves atoms into three strange quarks it is thought that in a kilonova explosion that is when two neutron or quark stars collide tiny droplets of this strange quark matter could be released and could travel through space indefinitely if one of these droplets so much as touched another star it would begin turning into a strange star as the name suggests this is a star made of mata that is mostly strange quark matter stars which are converted via these droplets would become much denser and more extreme shrinking down to quark star size and losing much of their luminosity until the transition is complete and the body resembles a neutron or quark star as such there really is no way of telling how many of these strange stars there could be in the milky way if any or how many are capable of releasing strange droplets when they explode so at the moment these are all just ideas but with that said there might be another line of evidence for their existence fast radio bursts fast radio bursts are a currently unexplained phenomenon caused by radio pulses in space from a high energy source ranging in length from a fraction of a millisecond to a couple of milliseconds the crusts of strange stars are proposed as a potential cause for these bursts because strange stars are so insanely dense even a tiny shift in its neutron star like crust would have a cascading effect resulting in the release of large quantities of electromagnetic energy which is forced up onto the poles before being ejected off at near light speed velocities and there is a good case to suggest that these relativistic emissions are a source of the fast radio bursts we can detect here on earth so we've covered stars in the distant past and we've covered stars in the present but what about stars in the distant future as the universe ages and its contents evolves new types of stars not possible in the universe today will be able to form in order to understand these hypothetical stars we must first consider what happens to a star that is not large enough to go supernova a star like our sun stars of this size up to between about nine or ten times the mass of the sun do not explode at the end of their lives rather they shed and disperse their outer layers into a planetary nebula as they exhaust their fuel what remains is a star core that is about the size of earth or slightly larger but that still retains about half its stellar mass resulting in an extremely dense body of electron degenerate matter known as a white dwarf the vast majority of stars in the universe are expected to meet this fate with only a small percentage of stars large enough to go supernova this white dwarf phase is the final extended light emitting phase of the star as it begins to cool down incredibly slowly over about 100 billion billion years in fact therefore white dwarves will eventually become the prevailing type of star and they will usher in a new cold age for the universe as this happens the metallicity of the interstellar medium where stars form is expected to increase to several times its current value when it does both the upper and lower bound mass limits for stars will fall meaning much smaller and lighter stars will be able to occur than the smallest that we see today these small stars will be a lot cooler too and as the threshold for fusion falls there will come a time where stars only four percent the mass of the sun will be able to fuse hydrogen with a surface temperature of only 273 kelvin that's just below zero degrees celsius and thus frozen by definition it would be a frozen star with swirling clouds of ice in its upper atmosphere and luminosities thousands of times lower than stars today and they too would survive into the distant future of the universe these frozen stars will share the universe with the remaining white dwarfs because white dwarfs are also constantly cooling down albeit very slowly eventually their temperature output will become insufficient for the star to stay luminous and this brings us to the final form of a small dead star a black dwarf an inactive sphere of matter with surface temperatures close to the coldest in the universe meaning no light or heat is emitted furthermore brown dwarfs which are failed stars not massive enough to fuse hydrogen but heavy enough to fuse deuterium will also reach this phase as they cool down and extinguish there are no such stars in the universe today as white dwarfs are expected to take quadrillions of years to cool to this level but one day black dwarfs will become the most prevalent type of star in space as the universe prepares to enter its second dark age what will happen next depends on a currently unanswered scientific question as to whether protons decay given enough time if they do then these star corpses will gradually dissolve back into atoms and particles over an incomprehensibly long time but if not then the body will stand the test of time outlasting even the heat death of the universe eventually heavier atoms will decay into iron which will turn the matter in the black dwarfs into spheres of solid metal aptly named iron stars the final fossils of the universe's once illustrious stars will be huge spheres of solid iron but this will also take an unthinkably long time perhaps 10 to the 1500 years which is a number so big i can't even fit it on the screen so probably not something we will ever have to worry about most of the styles we've covered in this video are hypothetical at best and some entail processes and phenomena that we are only just beginning to comprehend existing in the blink of an eye on a vast cosmic time scale as we desperately fumble around in the darkness of space trying to make sense of the past present and future of our reality perhaps the stars in this video are impossible and simply serve to do nothing more than highlight the gaps in our understanding perhaps in our lifetimes we'll begin to unravel a clearer picture of the past and future of the universe gradually piecing together the unendingly complex jigsaw that is nature but until we can conclusively identify those stars we cannot see we might as well just keep looking up at the ones we can see [Music] [Music] you

Channel: SEA

Views: 736,289

Keywords: Sea 1997, Sea1997, Sea, 1997, Space, OOTW, Out of this world, astronomy, science, hypothetical, population iii stars, cr7, galaxy, cosmos redshift 7, quasi star, thorne-zytkow objects, neutron star, pulsar, black hole, exotic matter, exotic star, quarks, free quarks, q star, magnetar, quark stars, electroweak stars, strange quarks, strange matter, strange stars, fast radio bursts, white dwarf, black dwarf, brown dwarf, iron star, frozen star, heat death, universe, documentary

Id: kqQ0e0twSgY

Length: 25min 22sec (1522 seconds)

Published: Fri Aug 21 2020