The Power of Neutron Stars

stars are among the most fascinating things in the universe they are the givers of warmth light and energy and are the nuclear engines behind some of the most extreme phenomena they form from gas clouds and carve out entire planetary systems releasing heavier elements in the process which allow more stars to form but the most fascinating thing about stars is what awaits them when they die when a star reaches the end of its life most of the time it does so in incredible fashion with a blinding cataclysmic supernova explosion but that is rarely the end we know that particularly massive stars many thousands of times larger than our Sun can collapse in on themselves so much that they form black holes but a dead star doesn't always have to form a black hole to be a destructive gravitational influence some stars collapse down to a fraction of the size they once were into a ball of tortured matter so dense and compressed that the effects are out of this world quite literally these dense graveyard star cores are known as neutron stars and their types properties and statistics are all absolutely mind-numbing in order to understand what a neutron star is you must first understand what a neutron is everything in the universe besides energy is composed of atoms the tiny fundamental building blocks of creation and they themselves are made up of tiny components called subatomic particles which come in three varieties protons which have a positive electrical charge electrons which have a negative electrical charge and finally neutrons subatomic particles with no net electrical charge protons and neutrons make up the nucleus of an atom and the number of each is the same in most elements so with that in mind how does it relate to dead stars well a neutron star is formed when a massive star between 10 times and 29 times the mass of our Sun reaches the end of its life and explodes at this point heavier elements in the core begin fusing iron because iron has no energy to give fusion is no longer generating outward pressure from within the star and there is suddenly nothing to stop the star collapsing under the weight of its own gravity the outer layers collapse inwards rapidly with nothing to counter them and when they reach the iron core this matter forces the interior into a much smaller space before essentially bouncing off the core and exploding in a violent supernova explosion these outer layers collapse fast at 25% the speed of light in fact this is so fast that particularly massive stars keep on collapsing indefinitely into a singularity creating a black hole a neutron star is formed by the level of massive star below star cores that are less than about four to five times the mass of the Sun in this case the core is not massive enough to collapse indefinitely but what remains at the collapse matter is miniscule in size compared to its previous form a star wants hundreds of times larger than the Sun collapses into an object the size of a city making it among the densest objects in the universe the reason they are called neutron stars is because the density and pressure on the interior is so great that the protons and electrons of the atoms within start to be crushed into one another generating long chains of strong Neutron rich material under conditions similar to those of the nucleus of an atom neutron stars are essentially giant atomic nuclei these dense dead stars have extremely strong gravitational influences and magnetic fields the chain reaction from the supernova explosion often causes the newly formed neutron start to spin incredibly quickly with some known to rotate up to 40,000 times per minute a speed which begins to deteriorate over tighten it wasn't until the 1960s that we were able to confirm the existence of these unthinkably dense objects but scientists have been speculating on them for some 30 years or so in the time leading up to their discovery in december 1933 just two years after the discovery of the neutron astrophysicists Walter Baden Fritz Viki proposed that supernova explosions could cause stars to turn into much denser more closely packed bodies as a result of the explosion a plausible theory but at the time we were sure we'd never be able to detect such an object even if they did exist as they would simply be too small to be observed from the earth but moving into the 1960s astronomer Franco pussini noted that if stars generated strong magnetic fields then the electromagnetic radiation this would emit should be detectable from the earth and sure enough in 1965 astronomers Antony Hewish and Samuel Okoye discovered a source of radio brightness in the nearby Crab Nebula this anomaly turned out to be the product of a rapidly rotating neutron star and so we were able to conclude on the existence of these terrifying postproduction stars and then in 1997 we did in fact see a neutron star through visible light what you see here is an actual photograph of a neutron star of a similar mass to our Sun which was discovered in 1992 the achievement of observing a neutron star 400 light years away in visible light is not to be understated whereas stars are millions of kilometers in diameter and radiate light most neutron stars are merely about 20 kilometers in diameter or just 12 miles one of the largest we've discovered today is PSR jo3 for a a neutron star in the constellation of Taurus with an estimated mass of about twice that of our Sun packed into an object just 25 kilometers wide making it smaller than the inner ring roads of City of London but huge for a neutron star although saying that size doesn't actually correlate to more mass within neutron stars in fact more massive neutron stars are actually smaller as their mass compacts more densely than in lighter neutron stars regardless of how big or small they are this size mass ratio gives them their incredible densities so much so that a single teaspoon of neutron star matter would weigh hundreds of millions of tons here on earth this incredibly compact concentration of mass means that the gravity of a neutron star is around two billion times greater than on the earth and while not as dense as black holes this gravity is still enough to bend and warp the radiation and light being emitted around it causing a gravitational lensing effect in fact sticking with our teaspoon of neutron star material if you were able to drop it to the ground from shoulder height the spoon would be traveling at well over 20,000 kilometres per hour before it collided with the ground our ideas on the nature of these stars is based on models but it is possible to infer some details of a neutron stars structure by studying living stars such as the Sun this process is known as astro seismology and it can reveal the inner structure of neutron stars by analyzing the spectra of star oscillations this is what gives us our insight into the real jaw-dropping numbers associated with these cocoons the surface or crust of the neutron star is an extremely hard outer layer whose surface temperature can reach up to 1 million degrees Kelvin this crust gives the neutron star a miniature landscape it can have mountains but these mountains can only ever hope to reach a few millimetres high the extreme outer layer is made mostly of iron leftover from the supernova and this iron is so compressed that it keeps the internal components sealed below the crust under unthinkable pressure under these conditions atomic nuclei are crushed together in long strings of matter trivially named nuclear pasta barely anything can breach this material it is among the strongest the most tightly packed matter in the universe as we move downwards towards the core we start to become a bit less sure we aren't sure what effect this much pressure this deep into the core would have or matter however we do know that it is able to keep atomic nuclei from decay allowing it to remain stable this internal mass density and pressure keeps any atmosphere the neutron star has tightly pressed onto the surface only a few micrometers thick and this is controlled by the incredible magnetic field produced by the neutron star the magnetic field of a neutron star can be anywhere between 100 million and 1 quadrillion times stronger than the Earth's making them the most powerful magnetic fields in the known universe every neutron star has its own terrifying density mass and attraction and there could be as many as 100 million of them in our galaxy alone most of these are old cold neutron stars which formed billions of years ago but some of them are young and display unique characteristics especially if they are rotating all neutron stars emit beams of radiation from their north and south poles and if those rotating emission points happen to be firing in the direction of the earth and we can detect these as pulses of light just like relativistic Jets firing away from crazy ours when these plumes point in the direction of the earth we can detect them from immense distances when this happens these neutron stars often resemble lighthouses firing beams a consistent rate in the direction of the earth from all over the galaxy when this happens we call these firing neutron stars pulsars and their rotation rates vary depending on their age and what's in their surrounding area some can rotate thousands of times every second we call the most rapid ones millisecond pulsars with the fastest reaching speeds of up to 65% the speed of light the word pulsar literally means pulsating star and they are named as such because of the pulsing sound they make as the beams sweep across the planet in sequence following the first noting of neutron stars in 1965 by Anthony Hewish two years later he and his assistant Jocelyn Bell Burnell detected a radio signal which appeared to be pulsing at a consistent rate with exquisite precision in fact this signal seemed so consistent and anomalous that it prompted widespread speculation that Bernal had intercepted a transmission from an alien civilization and so the signal was named lgm1 an acronym of little green men however we soon realized that this was in fact a rotating neutron star emitting beams of radiation in the direction of the earth since then we've discovered nearly 2,000 of these pulsars and most are cataloged as part of radio surveys hence why many of them are named with the prefix PSR for pulsar and so lgm1 joined the growing list of astronomical phenomena initially attributed to aliens but was actually a result of something natural but fear not these nuclear lighthouses may yet be of use in the discovery of our species [Music] the Voyager 2 spacecraft is a probe which was launched in 1977 to explore the distant ice giant planets but since completing this mission it now barrels through interstellar space carrying with it a golden record this record is mankind's CV it was meant to be found by aliens it contains information about our location in the galaxy this map was created using pulsars as a point of reference because they are extremely good timekeepers while their positions may change over time their pulse frequency remains highly consistent so the idea is that a civilization could look at this map which shows the position of earth relative to 14 nearby pulsars and they could find these pulsars based on their pulsation rates which we have attempted to inscribe on the record and then reverse-engineer our position it's a genius idea or at least it seemed that way in 1977 but in the years since we have learned that there could be hundreds of millions of these pulsars in the galaxy and though their rates are relatively consistent and measurable the direction in which they fire can change unpredictably meaning a bright beacon which once illuminated the earth with flashes of radio energy may just become another silent speck in the night sky finding 14 coincidentally placed pulsars in a galaxy was potentially billions it isn't even comparable to the needle and haystack analogy so whatever and whoever Voyager might encounter on its journey they'll likely never be able to work out where the probe came from even if they managed to decipher the map the faster a neutron star rotates the stronger the magnetic field it generates and for those exceptionally extreme neutron stars there is another classification a magnetar these are similar in size and mass two neutron stars but rotates so fast that they are even more extreme and deadly magnet ours can be caused by the supernova that created it or by the gravity of a neighbor around the neutron star whatever the case their magnetic fields are amplified exceeding 1000 times the strength of a normal neutron stars field which is already billions of times the strength of the Earth's it's a scale difficult to fully appreciate these fields are so intense that they often experience very strong x-ray bursts and when their shells crack blasts of x-ray and gamma radiation are emitted this can cause an aptly named star quake which can lead to a storm of solar energy trillions of times more powerful than the solar emissions of our own star unsurprisingly these magnetized are not very stable the strong magnetic fields tend to break down after about ten thousand years which is only the blink of an eye on a cosmological timescale and it is a much narrower window for us to exist to observe them therefore magnet ours are considerably rarer than neutron stars and pulsars there are estimated to be about 30 million inactive magnet ours based on the number we can currently observe most neutron stars are old spinning much more slowly than the young magnet ours and millisecond pulsars so the question is what happens to these aging nuclear capsules over time do they blow up collapse even further merge with one another well the answer can be all three loads of weird and wonderful things can happen to a neutron star especially if we give it a neighbor neutron stars can continue to gain mass and grow after formation and they grow in the same way that planets and moons do through accretion the gradual accumulation of matter as the object orbits neutron stars have an insanely strong gravitational influence and therefore attract a lot of extra mass from their surrounding areas this accumulation of mass can cause already rapid pulsars to spin even faster it can push young neutron stars into spin cycles and it can wake up older slower pulsars neutron stars attract the most matter in binary star systems binary systems are commonplace throughout the galaxy stars formed from the same collapsing clouds of gas that form star systems like ours and given their strong gravitational influences it's not uncommon to see stars in pairs orbiting each other as such it's not uncommon to see a neutron star in a binary star system the most common type of neighbor we see for neutron stars in binary systems is a white dwarf the final light of a dying star this could be because both stars in the system are old all the star has been stripped away in irradiated by the companion supernova and our orbits as a dying core or perhaps the neutron star is a visitor magnet ours barreling through space a fifth the speed of light can find homes in new star systems and like a spider crawling out of the dark these neutron stars then enter the systems and strip away the unlucky star down to its dying phase most of the time wherever the neutron star orbits will bring it to a collision as it spirals inwards however should the object which orbits the neutron star managed to remain a safe enough distance to avoid total destruction than the other star may survive to become a neutron star itself suddenly there are two of these incredibly dense powerful masses and their gravitational interactions can be felt from entire galaxies away where binary neutron stars orbit each other they spiral inwards and begin to draw closer and speed up as they do in the moments before they collide they reach a significant percentage of the speed of light and lose energy through gravitational radiation this interaction before the merging may be a source of gravitational waves disturbances in the curvature of space-time itself gravitational waves are caused by to accelerated masses they are like ripples in the fabric of reality which fly away from the source at the speed of light and this is exactly what we think happened when we detected gravitational waves in 2017 GW 1708 17 is the catalog name of a gravitational wave signal which was detected by the advanced laser interferometer gravitational-wave Observatory or LIGO and scientists believe that these ripples in space-time are the result of two neutron stars colliding in a galaxy over a hundred and forty million light years away with detectability across such vast distances it should come as no surprise that the actual collision is just as terrifying and far-reaching when the two neutron stars are within touching distance the tidal gravitational forces of each shatter the outer shells releasing the enormous reserves of matter track within into space which is under considerably less pressure and explodes in an appropriately named killer Nova explosion this explosion is a source of short gamma-ray bursts the most destructive electromagnetic explosions in the universe after this cataclysmic explosion taken place the two merging neutron stars will do one of two things they will either become a more massive neutron star all the two masses will collapse and form a black hole the lower bound mass limit required to form a black hole is between four or five times the mass of our Sun if the two neutron star cores combine but remain below this mass then they will combine to form a magnetar with the magnetic field trillions of times stronger than the Earth's alternatively the two dead stars will collapse in on each other and form a black hole which is infinitely dense as singularity it's an intriguing and bewildering process but the merger of neutron stars is actually quite a fruitful event the shuttering of neutron star shells releases loads of heavier elements which were fused by the style that came before it and these heavier elements mix into the clouds of hydrogen and helium gas in space the same clouds that form planetary systems the remains of killing over explosions is likely the source of most of the heavy elements in the universe and the solar nebula cloud which our solar system formed from 5 billion years ago likely contains the remains of neutron stars which exploded billions of years before in a profoundly younger universe neutron stars are just another tiny improbable piece of the unendingly complex puzzle that is the emergence of life from Stardust speaking of planetary systems what would it be like for a planetary system orbiting a neutron star we've observed planets around neutron stars before we detect them when said planet passes in front of the beams of a firing pulsar as such we refer to them as pulsar planets and we've known about them since 1991 and have discovered entire planetary systems orbiting them since then it's unlikely that these were the planets that orbited the star in the main stage of its life on the contrary all of the pulsar planets we have observed fall into three main groups the first being planets which formed out of the metal-rich debris leftover from the supernova explosion which formed the neutron star all the planet could be a captured planet the extreme gravity of a neutron star may just be enough to pluck a hurtling rogue planet out of the darkness of interstellar space and into orbit damming it to be radiated and ravaged by its new deceased host or three the planet might actually be the other star in the bind system which used to orbit the pulsar but that has been stripped down and solidified due to the extreme irradiation of the Pulsar in 2011 we discovered the companion of the pulsar PSR j17 1:9 it was a white dwarf star in the final stage of its life but it had most of its mass torn off by the Pulsar orbits and was spiraling inwards towards its companion destined to be shredded up and ripped to pieces however this star orbits its neighbour in an unlikely position a distance slightly smaller than the radius of the Sun just under 700,000 kilometers this isn't close enough to shred the planet entirely but the po stars influence is so strong that the carbon in the star has likely crystallized the neutron neighbour is now likely a diamond planet five times the size of the earth life on these neutron star planets is non-existent and hopeless those planets lucky enough to escape total destruction as subjected to torturous conditions the beams of gamma radiation x-rays and extremely solar energy would ravage any planet if a magnetar came within range of our planet say about the distance of the moon then you would start to notice fast our atoms would be warped and would change shape completely destroying your molecular structure and dissolving your body nothing can survive under the vise-like grip of a pulsar or worse a magnetar [Music] and so the final question is if neutron stars are virtually unbreakable and composed of the hardest materials in the universe then what happens when the amove will object meets its unstoppable force what happens when a neutron star is consumed by the only thing stronger and more powerful than itself a black hole well we may finally have an answer only a few months ago did those same gravitational wave Observatory Zin Italy pick up more ripples in space-time more gravitational waves created by a collision a little under a billion light-years away the signal is named s-19 r81 4bv and is believed to be the product of a neutron star being eaten by a black hole scientists analyzed the wave patterns from the two objects and determined that one of the objects must have exceeded five solar masses while the other was some way less likely meaning that this is a black hole and neutron star pairing although the distinction between the two remains unclear in this case regardless the waves were a product of the moments before the collision as for the collision itself well if the black hole in question is large enough then the neutron star could disappear over the event horizon with one big gulp this would release no energy beyond the boundary and would be somewhat anticlimactic if you were an observer looking on from the outside in this case however it's unlikely that the mass difference between the two is sufficient for the black hole to be capable of such a large gulp so some impact would have occurred the neutron star would be ripped apart by gravity and its matter would be dispersed in every direction some of this matter falls straight into the black hole whereas some of it may be ejected beyond the event horizon area meant speeds before falling back in again some of the debris will be flung out and will be under much less pressure in space causing it to explode violently the other debris won't escape entirely but will fall into orbit around the black hole along its accretion disk so these gravitational waves likely did emit from the site of a cataclysmic explosion but probably a less impressive explosion than when two neutron stars collide as of yet we don't have any visual confirmation neutron stars are the seeds of creation in the universe tiny incubators of super dense heavy elements and atomic nuclei they attract they destroy and they emit beams of radiation they produce the strongest magnetic fields in the universe and a second only to black holes in terms of their properties and mysteries looking into a black hole makes the gravity and pressure within seem almost silent and featureless but when we look at neutron stars we know that the true conditions are anything but [Music] [Music] you

Channel: SEA

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Keywords: Sea 1997, Sea1997, Sea, 1997, Space, OOTW, Out of this world, astronomy, science, neutron stars, magnetar, pulsar, neutrons, density, lgm-1, jocelyn burnell, nuclear pasta, supernova, kilonova, neutron star documentary, voyager 2, white dwarf, binary star, gravitational waves, black hole, neutron stars collide

Id: 7euiD_kZi4g

Length: 24min 1sec (1441 seconds)

Published: Wed Dec 18 2019

Reddit Comments

[u/zombimuncha]

Beautiful visuals. Makes me want to get an OLED TV.