A JOURNEY TO INTERGALACTIC SPACE

the concept of space is familiar to all of us generally speaking the knowledge of the average person is limited to some basic facts about our system and the universe around it but the most exciting things on the cosmos take place in remote areas not readily available to our eyes and if we look beyond the boundaries of the solar system a fascinating picture of infinite space opens up to us today i invite you on a journey to those mysterious places realistically quite beyond our physical reach and as we get further away from our earth we will be braving the most forbidding areas of space our flight starts in the vicinity of titan then we will move on to the most dangerous asteroids and a bit later take a look at pluto right after that we will set out to observe some potentially habitable exoplanets check out the micro quasar ss433 and then see what intergalactic space looks like as our journey draws to an end we will consider the future of our universe and try to predict what will happen after its demise i hope you have fastened your seat belts let's get going [Music] cosmo the first in outer space apart from the earth titan is the only celestial body in the solar system with liquid on its surface unlike our earth however this liquid isn't water but a mixture of liquid hydrocarbons for the most part methane and ethane oceans on titan were first seen in radar images which were beamed back by the cassini probe on the 21st of july 2006. in the period from 2004 to 2017 the space probe approached titan on 127 occasions thanks to these photos scientists were able to successfully map out the entire surface of this moon in fine detail analysis of the relief and its features revealed that the same processes were instrumental in its formation both on titans and the earth's surfaces the only difference lies in the fact that water was the main factor for relief formation on our earth whereas on titan it was liquid hydrocarbons as a result titan's surface is also covered by lakes seas rivers and bays just like that of our planet it also rains there on a regular basis too titans lakes of the most part rather vast but not really deep their number reaching 650 the biggest of them are referred to as seas or mares and they have been dubbed after mythical sea creatures kraken mare lygia mre and pangamare there are dunes on titan's equator which is explained by the fact that the climate in that area is the driest these areas account for 17 percent of the overall surface of this moon with mountains and labyrinths making up 14 and one and a half percent respectively most of titan's surface or 65 percent to be precise is covered by planes as for mountain ridges they stretch for several dozens of kilometers with a height reaching several kilometers only 23 impact craters have been discovered on titan their diameter over 20 kilometers which is not more than 0.4 percent of the total area most craters are believed to have disappeared due to highly intensive erosion processes that have been taking place for several hundred million years due to some organic compounds which include atoms of nitrogen titan and its atmosphere are of an orange hue now let's talk about big liquid objects on titan the area of kraken mare the largest one discovered on its surface is approximately 400 000 square kilometers and its length measures about 1100 kilometers located in the satellite's northern hemisphere this body of liquid is estimated to be up to 200 meters deep the second largest body of liquid on titan like mra is also situated in the northern hemisphere with its width measuring about 500 kilometers and its depth reaching up to 170 meters lygia mre covers an area of approximately a hundred thousand square kilometers the third and the smallest sea on titan pangamare is also the most northern of the three its diameter measures approximately 380 kilometers these seas are most likely to be made up of liquid methane and ethane as both gases are rather abundant in titan's atmosphere regularly forming dense clouds it must be due to evaporation of methane and ethane from the surfaces of these maoris that these gases can be found in the satellite's atmosphere there are some dark spots to be seen in images of titan's surface they are likely to be drifting chunks of ice that have emerged from the bottom as a rule this kind of hydrocarbon ice floats in temperatures close to 183 degrees celsius below zero if the temperature drops still lower nitrogen bubbles in the ice rocks will account for less than five percent which makes these rocks sink it is also highly probable that in some areas of titan there may be an ice shield enveloping liquid methane both below and above it's worth mentioning that the chemical composition of the liquid on titan is different depending on an area since it is liquid gases with different boiling points that account for most of the liquid on titan the chemical composition largely depends on temperature for example the chemical composition of the liquid at the pearls is different from that at the equator which is warmer apart from bodies of liquid on the surface there may also be a subsurface ocean of impressive proportions on titan and for all we know it may contain water this hypothesis was put forward as an inference from this idea following saturn's tidal effects the core may get heated up and a high enough temperature may be sustained for liquid water to be formed under titan's surface besides cassini's images from 2005 and 2007 revealed that some features of relief had shifted approximately 30 kilometers since titan is tidally locked to saturn that is it faces it with the same side at all times this shift may be accounted for by the fact that titan's ice shell is separated from the main body by a global liquid layer the subsurface water is thought to contain a considerable amount of ammonium which acts as an anti-freezing substance thus decreasing the water's critical freezing point coupled with a high pressure from titan's crust this may be an additional favorable condition for the subsurface ocean this ocean may well lie as deep as approximately 100 kilometers with its water rich in various sorts this liquid is most likely to be a mixture of salts and its chemical composition includes salts containing sodium potassium and sulfur the depth of the ocean is different depending on the area of titan with liquid freezing and forming an ice crust in certain areas the exceptionally high sword concentration makes it too harsh an environment to support any life as for titan's land there is a chance of encountering simple life forms on its surface titan's atmosphere is rather dense and chemically active containing diverse organic compounds this allows us to assume that there may be life in the atmosphere's upper layers it seems feasible that simple organisms could be sustained by gas hydrogen and also consume molecules of acetylene after digesting these in return they could produce methane it should be mentioned that relatively recently highly active organic molecules were discovered in titan's atmosphere the substance in question is called cyclopropanilidine this is an unstable and highly active material which cannot be observed on earth anywhere but in a laboratory environment scientists first came across it in 1985 and clouds of interstellar gas in space cyclopropanilidine is crucial in forming larger organic molecules its discovery on titan was the first case of finding it in the atmosphere of a planet rather than an interstellar environment this discovery will certainly help scientists to see titan's chemical evolution from a different angle there are also some alternative theories about life on this satellite according to these there could also be life forms in liquid methane rivers but this is feasible only on condition that these organisms live on hydrogen rather than oxygen and produce methane rather than carbon dioxide unlike organisms on our earth however since titan does not lie in the goldilocks zone and its surface temperature is as low as about 180 degrees below zero these hypothetical organisms would differ a lot from those we used to see on our planet lipid cell membranes for instance which are typical earth dwellers wouldn't be able to survive in such conditions some really bizarre analogues would then be produced by evolution processes and we can't venture even a wild guess as to what they would be like be it as it may climatic conditions on titan really are able to sustain certain forms of microbial life this is the main object of interest for nasa's dragonfly spacecraft planned to be launched to titan in 2027 to investigate and who knows perhaps this mission is destined to reveal something even more fascinating than we've already found out the search for alien life forms is undoubtedly an arduous task that will probably not yield any results until the next millennium but its global significance can hardly be overestimated if at some point we succeed in our attempts this will be a major milestone and the beginning of a new era in the history of mankind it will not only allow humans to enhance their own knowledge but also begin a long and scrupulous process of fostering relationships with intelligent beings from another world large objects do approach our planets now and then for example on the 14th of november 2020 asteroid 2020 vt4 with a diameter measuring about 10 meters past our earth at a distance of 383 kilometers from the surface that is below the international space station and most satellites even though known potential threats are monitored by scientists at all times the problem is that most asteroids are rather dark objects whose dimensions are quite modest by space standards which makes them hard to detect however an explosion caused by an impact of a celestial body with a diameter of just 10 meters would be tantamount to the atomic bombing of hiroshima it may not leave any radioactive waste but a blast this powerful would wipe a little town right off the face of the earth an asteroid with a diameter measuring 50 meters that is as big as a modern multi-storey building would unleash a power of several dozen kilotons on impact which would be enough to raise an entire city almost to the ground if an asteroid this large were to fall into an ocean it would cause a tsunami reaching up to 10 meters which would drink destruction all the way it went traveling for hundreds and thousands of kilometers from the site of its impact where this asteroid's diameter to measure a kilometer or so it would cause mass destruction throughout an entire continent the force of the explosion on impact could reach as much as thousands of megatons and tnt equivalent and its consequences would haunt the planet for many years to come it is highly likely that the human civilization would not survive a calamity of this scale nor would other living creatures with the only exception of protozoans and exceptionally enduring organisms mass extinction events did take place in the history of our earth the most notorious of them cretaceous tertiary extinction event about 66 million years ago it is posited that dinosaurs and a number of other species died out as a result of it as for the most large-scale mass extinction event it took place approximately 251 million years ago coming in between the permian and the triassic periods based on results of paleontological diggings it was estimated that about 90 percent of sea species and 70 percent land species died out as a result one of the things that caused both of these dramatic calamities is believed to be the fall of a large asteroid today the number of potentially dangerous objects is estimated to be in the region of one and a half to two thousand although this number may reach four to six thousand according to the data provided by the wise telescope since they're so small and dark these celestial objects are rather hard to spot for example the size of the asteroid dubbed 2008 dc3 which burned up in the atmosphere just above sudan in 2008 was anything from 2 to 5 meters it was spotted just 20 hours before it would have impacted the earth fortunately nobody was hurt there is a special rating scale known as the palermo scale it is a generalized scale reflecting potential impact risk posed by this or that celestial body which takes into account the body's kinetic energy and the probability of hitting the earth the higher the value the bigger the threat to our planet if a body's palermo scale value is below -2 this body is practically safe asteroids with values between -2 and 0 do not pose any immediate threat but require monitoring at all times as for objects with a value above zero they are realistically dangerous for the earth at this point there isn't a single celestial object out there with a positive palermo scale value and there are only two asteroids in the yellow alert zone that is their value is between -2 and 0. both of them fall into the category of the apollo asteroids celestial bodies whose perihelion lies closer to the sun than the earth's aphelion and whose orbital semi-major axis is bigger than that of the earth thus these objects cross our planet's orbit from the outside the bennu asteroid designation 1999 rq36 with a potential hazard index value minus 1.69 poses a smaller threat to the two in the year 2135 it will find itself just 300 000 kilometers away from the earth which is slightly closer to us than the moon bennu's average diameter measures approximately 500 meters and the asteroid's mass is anything between 60 to 78 million tons if it were to collide with our earth the resulting explosion would be tantamount to about a thousand megatons and tnt equivalent which would almost certainly cause major catastrophic disasters all over the planet in 2016 nasa launched the osiris-rex probe to bennu in order to obtain samples of the minerals making up the asteroid the probe is scheduled to get back to the earth in 2023 the more hazardous of the two asteroids is 1950 d a with a palomo scale value minus 1.42 today it has the highest probability of hitting our earth its diameter measures about 1.3 kilometers and its mass can be anything from 2 to 4 billion tons 1950 da's orbit is elongated and elliptical and it crosses the orbits of our earth and mars 1950 da's closest approach to the earth is expected in 2035 but a hazardous approach will take place only as late as on the 16th of march 2880 what would await us if the asteroid did impact the earth let's assume no preventive measures have been successful to deflect this body and the disaster is inevitable an enormous chunk of rock with a diameter almost one and a half kilometers and a mass that could be two to four billion tons heading towards the earth at a speed of about 14 kilometers per second this would be the speed of 1950 da at the moment it hit the earth if an impact event did occur as estimated by nasa of course part of the matter making up 1950 da would burn up and disperse in the atmosphere as the asteroid slowed down and the main body would be likely to break up into several large rocks and a great number of small bits depending on their size each of them would cause an explosion of not less than 20 kilotons on impact for the earth's crust that's the average power of a modern nuclear bomb with a comparatively modest charge the overall power of the explosions would most likely be over one and a half thousand megatons with a bombarded area larger than that of europe all constructions within the radius of 300 to 500 kilometers would be raised to the ground and even reinforced underground bunkers wouldn't guarantee enough safety the energy of the shock wave would allow it to sweep around the earth several times while gradually slowing down and bringing more destruction on its way with every lap if the asteroid were to fall into an ocean a giant tsunami would rise 40 meters or higher tsunamis normally travel for thousands of kilometers and as they go their destructive forces practically don't diminish therefore coastal areas of the continents lying near the site of the impact would be submerged in water with cities and villages effectively wiped out multiple impacts of bits of rock would raise tons of dust in the atmosphere winds would scatter these dense clouds all over the sky and most sunlight would not reach the planet which would cause a sharp temperature fall this phenomenon is known as nuclear winter it is highly probable that an impact of this scale would affect not only the crust but the mantle as well the shock wave would wake up volcanoes and they would erupt all over the planet which in its turn would cause the second wave of tsunamis and earthquakes tons of ash released in the atmosphere would contribute to further temperature drops there is quite a popular belief that after an asteroid hit the earth it would affect its orbit or orbital period this would lead to dramatic climate changes and even render the planets completely incapable of sustaining life however according to some estimates an impact of even the biggest asteroid in the solar system would not be enough to do so an object realistically able to noticeably change the earth's orbit should be as big as the moon or pluto at the very least be it as it may if it were to happen the consequences of an impact of this scale would be much graver than just a change of orbit or orbital period the potential impact risk of 1950 das hitting our earth is just 0.012 there is no room for complacency though as the impact probability may rise following a change of the asteroids orbit as a result of collisions with other celestial objects that may well take place for a long while it was believed that the humanity hadn't advanced enough to prevent any hazards of asteroid falls all we could do was just observe potentially hazardous objects actually doing something about them like destroying an asteroid or changing its orbit was confined to science fiction films and books however science doesn't stand still even in 2004 when a threat posed by apophis was considered grave enough it was proposed to cover its surface with light reflecting film this way sunlight pressure would change the asteroid's orbit other suggestions included nuclear bombings as well as special power thrusters powerful enough to shift orbits of celestial bodies [Music] in 2018 nasa in collaboration with spacex approved the dart program whose aim is to deflect the asteroid's trajectory by making it collide with an artificial spacecraft the binary near-earth asteroid didymos made up of two components with diameters measuring 800 and 150 meters is the target for the dart demonstration the launch of the spacecraft is planned for 2021. celestial bodies and the solar system may be closely monitored but there is always a risk of somebody previously unknown to us arriving from the galaxy's outskirts and heading towards the earth orbital periods of some comets and asteroids around the earth may last hundreds and even thousands of years and their small sizes and dark surfaces render these potentially dangerous visitors barely detectable still the odds of such a disaster as an impact event are extremely small and in fact there are many more dangers that may befall the human race on our own planet pluto is the largest transneptunian object in the solar system it is also the largest object in the kuiper belt just like most bodies in that region of space pluto is mostly made up of rock and dice and its mass is relatively small approximately 0.22 percent that of the earth just to get a slightly broader picture let's compare pluto with the moon pluto's mass is about six times smaller and its volume is about three times smaller pluto's total area is 17.7 million square kilometers and we're briefly back to earth again to compare it with the area of russia the largest country in the world which is slightly smaller 17.1 million square kilometers as for pluto's diameter it reaches 2376.6 kilometers which is 1097.6 kilometers less than that of the moon as for pluto's atmosphere it is for the most part comprised of gases evaporating from the ice on its surface today we know that its chief component is nitrogen apart from that two other gases are methane and carbon monoxide under the influence of high-energy cosmic radiation other more complex compounds form from these elements on account of pluto's surface temperature these compounds are not volatile ethane ethylene and acetylene there are also the so-called tholins on settling on the dwarf planet's surface they have a peculiar property of giving it a brownish hue the average surface temperature on pluto is 50 kelvin that is 223.15 degrees celsius below zero with every kilometer higher up this indicator increases by approximately seven degrees and so the atmospheric temperature is 40 degrees higher than that on the surface this could be accounted for by the greenhouse effect caused by methane we're used to thinking that pluto's orbit is stable and unwavering however on closer observation it transpired that pluto's movement is rather chaotic and can be defined in non-linear equations it takes a lot of observation to be able to detect that when carried out in short time spans observations reveal seemingly regular movement in reality pluto's orbit slightly shifts in every period eventually changes to such a point that it is impossible to retrace its initial trajectory this dwarf's planet's rotation is quite peculiar too namely it is retrograde which is also the case for both venus and uranus it means that they rotate in the direction opposite to that of the other planets around the sun a day on pluto lasts 6.4 earth days due to its remoteness and small mass pluto is a rather challenging celestial object to study even very big telescopes show it to us is a tiny spot seemingly not much different from a regular star we have been able to acquire a certain amount of data with the help of the hubble space telescope nevertheless the greatest and most important portion of information was made available after the launch of the new horizons mission the first photo of pluto was made back in september 2006 when the space probe was testing its lori camera as the spacecraft approached pluto closer and closer more and more features of this dwarf planet were revealed to us thus the object's surface was seen to be far from homogeneous albedo that is diffuse reflection properties of the surface varies from ten to seventy percent depending on the area of the object which makes pluto the second object in the solar system after arriapatis in terms of contrast in albedo this diversity causes periodic variations in pluto's luminosity and spectre as it rotates the dwarf planet's interior must be made up of 50 to 70 percent of rock and 30 to 50 percent of ice its dense rocky core must be embedded in an icy mantle about 300 kilometers thick according to spectral data there is water ice on pluto's surface as well but it is mostly camouflaged by a layer of more volatile ices there is also frozen methane and carbon monoxide as well as traces of other compounds generally forming with methane and nitrogen when exposed to powerful radiation in particular these are rethane nitriles and phthalins which make pluto look brownish on the fifteenth of july 2015 the new horizons space probe flew by pluto 12 and a half thousand kilometers away from its surface both sides of the dwarf planet were photographed during the flyby the one to be seen on closest approach and the opposite one thanks to these images a vast heart-shaped area measuring eighteen hundred by fifteen hundred kilometers was identified it was later nicknamed pluto's heart or tombow regio the left part of this area is believed to be a crater filled with crystal nitrogen also two mountain ranges were identified in this area the height of the first reaches 3500 meters and it was given the name the tensing montes the height of the second one dubbed the hillary montes reaches up to 1500 meters the most notable geological object found on pluto is sputnik planitia this trench is likely to be an impact crater with a diameter measuring 1492 kilometers sputnik planitia is filled with frozen gases and is streaked with a great number of grooves which divided into irregular cell-like areas measuring dozens of kilometers there may also be cryovolcanism on pluto the last image taken by the spacecraft looks to be indicative of just that the potential cryo volcano that can be seen in this picture was dubbed right mons the surface in the picture is comparatively young by space standards and practically devoid of impact craters this shows that the crust in this area was formed relatively recently and if right mons really is a cryo volcano its enormous size of 144 kilometers across and four kilometers high easily makes it the largest cryovolcano in the outer area of the solar system among other interesting features discovered by new horizons there is a blue stratified haze enveloping the whole of the dwarf planet in the images the haze is seen to reach over 200 kilometers high and is registered by the ultraviolet spectrometer to persist to the point of 300 kilometers above the surface the haze is likely to be made up of particles of non-volatile elements that originate from atmospheric gases the ones i've already spoken about these elements gradually settle on the dwarf planet's surface and that is the way this effect is produced the new horizons mission is scheduled to continue until 2026 apart from studying the objects in the pluto system the spacecraft has already provided insights into other kuiper belt objects too and even though its fuel supply is insufficient for a dramatic change of course the radioisotope generator's energy should be enough to last it for another 10 years immediately after the space probe had flown by pluto astronomers used the hubble telescope to look around for other objects that could be observed within the framework of the mission the first of them ultimatuly is a binary asteroid in the kuiper belt whose two components diameters measure 19 and 14 kilometers it was closely passed by new horizons on the 1st of january 2019 another object was the asteroid 2014 pn70 measuring 40 kilometers across it was passed by the probe in march 2019 excitingly apart from that having traveled 8 billion kilometers away from the earth new horizons reached a great vantage point for better observation of the stars closest to the sun proxima centauri and wolf 359 in april 2020 the spacecraft was also used for double checking the distance to these stars apart from the objectives mentioned this amazing mission stands a good chance of being able to reach quite a few more in the future while the spacecraft keeps beaming back new images to the earth we will be able to conduct research based on the photos of the celestial bodies it has already passed for example the pictures of pluto's largest moon charon taken on their brief encounter with a space probe several centuries ago it was quite unimaginable to admit of discovering exoplanets however everything changed in 1992 as the polish astronomer alexander washington was studying the pulsar psr-1257 plus 12 it was noticed that its pulsation period was irregular which was accounted for by the influence of two planets with a mass four times that of our earth this hypothesis was later confirmed which led to the conclusion that the first planetary system beyond ours had been discovered there are three objects in that system two of which have a mass similar to that of the earth and are comparatively close to their pulsar in the constellation virgo due to the fact that it is rather remote from us and the conditions for sustaining life are poor the psr1257 plus 12 system is of little interest to scientists although its discovery led us to believe that the search for earth-like worlds may eventually be a success just three years later the first exoplanet orbiting a sun-like star was discovered 50 light years away from the earth and was dubbed 51 pegasi b just several years later the number of confirmed exoplanets counted dozens and today 4173 exoplanets in 3096 different planetary systems unknown to science in addition a great number of earth-like objects is still awaiting the confirmation of their status which is possible after a secondary registration with telescopes on earth the number of celestial objects of this kind in the entire milky way may well be over a hundred billion with about one-fifth of them bearing resemblance to our earth interestingly most of the discovered earth-like exoplanets are located not very far from our system ros128b this planet was discovered in 2017 by european scientists with the help of the high accuracy radial velocity planet searcher or halves at the observatory in chile the object is located in the single star system ros 128 which is the 13th closest star to us the object is a faint red dwarf with a mass of 0.15 that of the sun it was possible to discover this planet thanks to its gravity which leads to minor variations of the stellar spectrum of its parent star while observing these variations harps is able to spot planets around stars in this particular case it took the telescope approximately 10 years to collect sufficient data before discovering this planet this effort paid off ros-128b became the second earth-like exoplanet lying closest to us it is located 11 light years away from the earth in the constellation virgo apart from that astronomers claim it to be the most moderate of all known exoplanets due to its mass its temperature and its rather calm parent star it takes this planet 10 days to orbit its star it finds itself in the habitable zone since the temperature of the photosphere and luminosity of ros 128 are low it is also classified as an earth-like type of planet and at the moment ros128b is one of the most likely candidates to be a potentially habitable exoplanet besides research done in 2018 confirmed that its climate is favorable enough to sustain life another exoplanet on the list of earth-like objects located closest to us is glieser 667cc this celestial body is part of the triple star stellar system glieser 667 in the constellation scorpius it consists of two orange dwarves and one red dwarf the first two components a and b lie 12.6 astronomical units from each other with the third component orbiting them at a distance of 230 astronomical units the earth-like planet in this system was discovered on november the 29th 2011 in the geneva observatory with the help of the doppler method the object is 22.7 light years away from the earth and is the second exoplanet orbiting its host star the mass of gliese 667cc is about 3.8 times that of the earth while its temperature range may be rather similar to the terrestrial one modeling at the planetary habitability laboratory managed by university of puerto rico reveals that the average surface temperature of the atmosphere of gliese 667cc must be approximately 27 degrees celsius the planet receives about 90 percent of energy compared to that received by the earth from the sun also gliese 667cc is almost certain to be locked in its orbit that is it faces its star with one on the same side if the planet's orbit does not curve too little and if its mass is not too big the greenhouse effect produced by the rather dense atmosphere must be quite sufficient to create favorable conditions for primitive life forms [Music] the next deserving object in our list is hd855 an exoplanet orbiting the orange dwarf hd-85512 in the constellation velar its star is a single k-type main sequence star with the mass 0.69 that of our sun as for its age it is more than 5.6 billion years old the exoplanet discovered close to it is located 36 light years away from the earth and its mass is 3.6 times that of our planet at the same time hd 85512b be one of the smallest planets in the habitable zone it was spotted in august 2011 with a harps telescope the supposed steady-state temperature of its surface is something around 25 degrees celsius if the planet's atmosphere is identical to that of the earth its surface temperature should reach 78 degrees celsius it is also highly probable that there is liquid water on this celestial body which is why for some time it was believed to become the most likely place where life would be discovered first apart from the objects mentioned there is a number of other celestial bodies in space located quite close to us which also boasts some unique features many of them may well contain various life forms and maybe not quite as far from us as we would imagine however we should bear in mind that some half a century ago man did not possess a tenth of information known to us today and in the future the progress of our discoveries is going to escalate even more dramatically for example on december the 18th 2019 the k-op space telescope was successfully launched in orbit by the european space agency it is specifically aimed at exploring exoplanets using the transit method it may be this spacecraft is to contribute to the list of earth-like exoplanets and it may become the telescope to first discover alien life forms in the universe science does not stand still and every new day bears witness to the fact that mankind continues to actively stride forward if this progress does not lose its momentum sooner or later we are bound to find an answer to the eternal mind perturbing question are we alone in the universe and i hope the answer we get will prove that life is not a mere accident but a logical consequence of the evolution in our universe as a rule micro quasars are x-ray binaries that is stellar systems made up of two components one of them is a regular star similar to our sun the other component is a compact object like a black hole or a neutron star matter in such micro quasars is constantly in the process of accumulating in the compact object which is accompanied by occasional outflows of matter at great speeds these outflows are known as jets and the nature of these jets reminds one of processes taking place in regular quasars now it is not a regular occurrence in ordinary quasars meanwhile as the mass of a micro quasar is smaller than that of an ordinary quasar jets may originate here practically on a daily basis the principal difference between micro quasars and ordinary quasars is in their mass and the frequency of matter outflows for example the mass of the compact components and micro quasars is considerably smaller than the mass of those in regular quasars it is just several cellular masses just to compare the average mass of a supermassive black hole in the center of a quasar may be approximately as much as a hundred million solar masses as for the mass of the black hole likely to be found in the center of ss-433 it must be just a few dozen solar masses the accretion disk of a micro quasar is intensely luminescent with emissions in the optical and x-ray bands a regular quasar is an astronomical body boasting the highest luminosity among other objects in the observable universe according to contemporary scientific views these celestial bodies are active cores of galaxies where a supermassive black hole sucks in matter all around it thus forming an accretion disk as for the disk itself it is a source of very powerful luminosity just to give you an idea its luminosity may sometimes be hundreds of times as intense as that of all stars in a galaxy like ours combined to date over 200 000 quasars have been identified we're able to observe some of these quasars in the sky even without using a telescope and so the rate of discovering new objects of one or the other category is another principal parameter by which regular quasars and micro quasars differ if we look at the list of known micro quasars it contains just a few entries so far the first micro quasar was discovered back in 1978 when a source of unusual radio and x-ray emissions was detected by two astronomers from the university of cambridge as they were looking for debris left over from supernovae detected in the constellation aquila this source was later dubbed ss433 the object under scrutiny is an eclipsing x-ray binary system one of its components is likely to be a black hole as for the second component it is a star of spectral type a that is a main sequence dwarf star of a whitish hue it is assumed that this star's mass is 10 to 30 times that of our sun and more likely than not the dwarf used to be considerably heavier in the earlier stages of its existence its surface temperature is thought to be anything from 7000 to eleven and a half thousand degrees kelvin this temperature range is typical for stars of this type it is actually its temperature that gives the star its pale yellow tint in fact if we look at the stars closest to the sun then sirius altair and viga fall into the same class as this star ss-433 is located within the supernova remnant w-50 sometimes also called the manatee nebula the age of this nebula is estimated at approximately 20 000 years and the distance between the nebula and the earth measures about 18 000 light years the jets from ss-433 distort the clouds surrounding the w-50 nebula according to a certain theory the w-50 nebula and the micro quasar ss-433 are actually related and came to be as a result of one in the same supernova event which supposedly took place around 20 000 years ago it takes either of the two objects in the system 13.1 days to orbit the common mass center in fact the way the ss-433 system works is quite exciting with both components constantly interacting with each other matter from the second component that is the regular star flows to the first component or the primary supposedly a black hole thus forming an accretion disk around it as it spirals the matter heats up to extreme temperatures and emits x-rays some part of the smatter leaves the system in two jets at the rate of approximately 26 of the speed of light that is 79 000 kilometers per second in 2019 thanks to the alma observatory astronomers managed to get detailed images of ss-433 it was clear from the emission structure that the micro quasars jets themselves are rather narrow and their shape is irregular and has nodes further studies of the object showed that the shape of the jets is distorted as a result of precession that is a process when the jets slowly rotate on their axis as they spiral the diameter of either of the two jets ejected from the micro quasar in two opposite directions measures approximately 5 000 times the diameter of the solar system as ss-433 is relatively close to the earth it is particularly valuable to scientists studying the phenomenon of micro quasars images beamed back by the alma observatory showed its jets for the first time and it also helped establish the direction these jets point out is never the same just like a top the spinning toy gradually slows down they too rotate on their axis which is perpendicular to the plane of the accretion disk the armor images boasted another outstanding feature the shape of ss-433 was predicted in fine detail thanks to spectroscopic measurements that had been done in 2018 using the global jet watch telescopes and so the actual shape largely corresponds to the new images where ss433 is really seen to have a shape reminding one of a corkscrew it isn't a rare occasion when jets like that originate here or there in the universe as a rule jets of plasma also known as relativistic jets are spewed out of the centers of active galaxies quasars and radio galaxies when this occurs there are usually two jets as such pointing in the opposite directions and this is exactly what we can observe in the case of ss433 today the phenomenon of jets like that wants deeper studying it is believed that jets originate following the interaction between magnetic fields and the accretion disk around a black hole or a neutron star as for their size it may be staggeringly enormous in the case of the radio galaxy 3c one two zero for example the jet stretches for at least several kilo pass away from its source it is highly probable that in the future the regular star in the ss433 system will shed its outer layer completely as a result of the influence of the compact object its core meanwhile will remain hot and thus the star will qualify to be called a hot sub dwarf later the star is to be gradually sucked in by the black hole and sooner or later after this process is completed the ss433 system will assume a classical look it will comprise just the compact object the process of this system's evolution will of course continue for thousands of years so we have plenty of time to study this phenomenon and while the micro quasar ss-433 is active we will have many opportunities to carry out detailed observation that would help us understand the nature of this celestial object let's keep in touch predictably enough the term intergalactic space is generally used to refer to parts of space between galaxies it is believed that certain portions of these areas are practically devoid of any matter which makes their composition quite close to that of absolute vacuum with some of its areas stretching as far as millions of light years in all directions intergalactic space is for the most part filled with ionized gas generally this gas is hot hydrogen whose density here is 10 times less than that in interstellar environment namely less than one atom to one cubic decimeter there are also heavier elements to be found here as well like carbon oxygen and silicon some part of intergalactic gas is concentrated in clouds differing from each other very much in terms of density and temperature interestingly the chemical composition of their gas is diverse it may contain atoms of hydrogen helium carbon nitrogen oxygen sulfur and various metals it is this gas that more likely than not feeds stellar formations in all galaxies there are also much larger objects to be found in intergalactic space for example stars were spotted there quite recently the total number of intergalactic stars in the observable universe may reach several trillion within the milky way alone around 650 of these rogue stars have been pinpointed so far as a rule intergalactic mata doesn't emit any light and is mostly invisible to the potential observer that is why its discovery was actually made by pure chance it all started with quasars which were discovered in the 1960s very soon scientists noticed that the light from the quasars had certain missing pieces in some spectra these particles were absorbed by something in between quasars and astronomers telescopes it later transpired that this invisible matter was the gas of the intergalactic medium the igm in the decades that followed vast accumulations and filaments of gas and heavier elements were discovered in intergalactic space and even though at first glance it appears to be empty its dimensions are so mind-blowing that there must be more matter evenly distributed around it than there is mata in all the galaxies of the observable universe combined it is safe to assume that some part of intergalactic gas has been left out there after the hypothetical big bang still as there are heavier elements in its composition it may only mean that many of these elements used to be part of interstellar dust lost by other galaxies intergalactic gas actually plays an important role in the process of the universe's evolution under the influence of a galaxy's gravitational pull gas is gradually sucked into galaxies at the rate of one solar mass a year which is quite close to the rate of star formation in the disk of the milky way apart from that matter exchange among all galaxies occurs thanks to this process the point is that stars in a given area of the universe collapse and release part of their matter in intergalactic space having been released the mata becomes part of intergalactic gas and so later takes part in the processes of star formation in other galaxies consequently star formation in galaxies will not stop while there is still intergalactic gas around pulled by gravity substantial portion of intergalactic gas is matter remaining after supernovae which is why temperatures in some areas of intergalactic environments are extremely high sometimes reaching as much as several million degrees celsius the high temperature of some areas may also be accounted for by electromagnetic radiation emitted by intergalactic black holes following mata accretion on their surfaces or else by powerful streams of energy emitted by still more massive black holes intergalactic gas plays the role of raw material in star formation while intergalactic space is some sort of a tank used for its storage the mechanism of intergalactic gas recirculation hasn't been studied deeply enough first of all because unlike galaxies which are bright and easily seen this gas emits no light to speak of in their attempt to study this phenomenon astronomers have devised supercomputer foggy foggy modelled the patterns of intergalactic gas movements and it is possible to observe how gas traveled around galaxies in the course of 13 billion years most of this matter is carried to intergalactic environment by stellar wind that is thanks to the process of mata flow from stars to areas beyond their galaxies it should be mentioned that this occurs when particles in a star's atmosphere accelerate to speeds exceeding the escape velocity of this star stellar wind is crucial for stellar evolution as a result of this process the mass of a star diminishes and the intensity of this process has a direct impact on this particular star's lifespan also stellar wind is capable of carrying mata enormous distances through space away from its departure point as it were moreover it may have an impact on matter around it by sharing some of its kinetic energy results of this process may be clearly observed in the shapes of some galaxies or nebulae for instance the emission nebula ngc 7635 nicknamed bubble assumed its shape as a result of this process and in the case of galaxy m82 also known as the cigar galaxy we can observe how stellar wind from a great number of stars caused clearly seen matter rejections from the galaxy [Music] apart from the debris left over from supernovae there is also intergalactic dust to be found in this environment today it is posited that it is intergalactic dust that is to blame for jinxing estimations of distances on the intergalactic scale for example when supernovae quasars or other galaxies are being observed among its many properties it is capable of forming clouds by 1980 four such nebulae had been pinpointed within several megapass sects from the milky way as for intergalactic stars they are rather difficult to detect and explore some of them have been spotted in the x-ray spectrum with the help of the chandra x-ray observatory many of them are binary systems made up of one regular star as one component and one compact heavy object like a black hole is the other when such celestial bodies lie close to each other the more massive component attracts matter from the regular star while flowing to its new host mata spirals away from its source to form an accretion disk this disk compresses and heats up to extremely high temperatures and as a result it does not simply become luminescent but starts emitting x-rays it is next to impossible to spot most objects of this kind using regular telescopes meanwhile rogue stars inhabiting voids may eventually prove to be quite a common thing rather than something extraordinary and perhaps about half of starlight is actually emitted by stars lying beyond the boundaries of galaxies it is hard to tell how big their number may be and today it is barely possible to imagine that man will ever visit those places objects lurking in those mysterious parts of space may be of considerable interest to science and who knows perhaps it is intergalactic space that will be scanned with all telescopes by scientists in a few centuries time still for now this environment is just another mystery of the universe quite beyond our reach at this point it is places like this that really thwart our ambition to completely figure out space and its properties and it is places like this that drive us to take keen interest in how it all works the earliest theory of the genesis of our world is what is known as theory of the stationary universe or steady-state universe supporters of this theory claim that the universe has no beginning and no end it has always been and always will be in its steady state of equilibrium however very soon scientific estimations prove this theory likely to be wrong as there are some irreversible processes taking place in the universe in the 1910s and 1920s the big bang theory was formulated and widely popularized today it is one of the most consistent scientific theories and it is able to account for the universe's genesis and evolution dozens of scientists contributed to the development of the big bang theory and albert einstein's works on the general theory of relativity laid the theories foundation the main conclusion this theory enabled scientists to arrive at is the supposition that the fate of the universe depends on dark energy a theoretical type of energy causing space to expand be it as it may at this point it is quite impossible to say anything definite about this physical phenomenon there are a great number of theories about this and each of them has its praiseworthy aspects and shortcomings according to data we possess today the age of the universe is calculated from the moment of the big bang and is estimated at slightly less than 14 billion years the universe is constantly expanding and depending on the density of dark energy it will either expand forever at a regularly increasing rate or else the expansion will slow down and reverse in this case the universe is bound to compress into an infinitely small singularity similar to what it originated from today science is not ready to give a definite answer to the question which of these two possibilities will prevail however it is ready to suggest at least two equally possible scenarios of what may happen next referred to as the big rip and the big crunch the universe's expansion rate is proportional to distances between objects the further some objects are located from each other the higher the expansion rate imagine a balloon pumped with air there are two dots on it if we pump still more air into the balloon the dots will get further away from each other that's the way the expansion of the universe works it is space itself that expands the further the dots are initially located the faster they get still further apart at a certain point this rate exceeds the speed of light this point is known as the event horizon all objects beyond it disappear from view and they drift away beyond the reach of the most advanced telescopes never to be observed again just imagine first the remotest galaxies and clusters will disappear from the sky then one by one the milky way stars will fade away and to crown it all it will be the turn for our sun to go dim what a gloomy sight if the big rip theory holds good the universe's expansion rate will be constantly on the increase this will lead to expansion forces gradually overcoming gravity forces following that first galaxy clusters and then galaxies themselves and star clusters will be broken up after that it will be the turn for stellar systems to disintegrate as host stars will not have sufficient pool to keep their planets and satellites from floating away at the next stage matter will be reduced to atoms and these will be reduced to subatomic particles matter will effectively cease to exist after this physical laws as we know them will cease to be and any further developments are quite impossible to predict observations today show that space expands and the expansion rate is on the increase however we're not familiar with the nature of dark energy it may well have properties unknown to us at this point and these may reverse the expansion processes as a result the universe will start contracting this may well happen if general gravitation created by all matter in the universe exceeds its expansion force this scenario is what is known as the big crunch in this case processes in the universe will run in the same manner until its size decreases five times galaxy clusters will come together as one supercluster which in essence will fill the entire universe considerably shrunk by this point meanwhile inside the galaxies events like births and deaths of stars planet formation and so on will keep taking place just like before when the universe contracts 20 times more its volume will account for just one percent of that of today's and all galaxies will blend into one the relic radiation temperature by that time will measure 274 degrees kelvin and it will still continue to grow this means that there won't be any liquid water left in the universe and water is vital for biological life as we know it further contraction of space will cause the universe to heat up even more planets will first be burnt and then melted all matter will crumple into an enormous cloud of boiling plasma after that atoms and subatomic particles will disperse and eventually the universe will collapse into a singularity similar to the one it used to be when it was born there is a theory which is a kind of a spin-off of the big crunch theory it is known as the big bounce theory according to the big balance theory on reaching the state of singularity following the big crunch the universe will be reborn as a result of yet another big bang and the cycle will repeat itself again and again supposedly forever as far as it is possible to speak about eternity and conditions devoid of time and space i will repeat myself yet again by saying that our knowledge about dark is too meager to speak about the duration of any of these scenarios for all we know the next big rip or big crunch for that matter will take place in a period when there are still stars and planets around but what if it isn't the case what will happen to the universe if its ultimate fate is still extremely remote in time still the laws of physics imply that the universe as we more or less know it cannot exist forever there are four clearly defined epochs in cosmology and each of them is associated with this or that particular phenomenon we live in the so-called stelliferous era there is a lot of interstellar gas in the parts of the universe around us it is used as raw material for stars to form from and used stars are born from this gas and the process will continue until all interstellar gas has been depleted this epoch is expected to be over in the period from 1 to 100 trillion years from now by that time the sun and the overwhelming majority of other stars will have depleted their nuclear fuel subsequently turning into white dwarfs neutron stars or black holes i've actually already spoken about it in an earlier video the next era is known as the degenerate era there will not be any main sequence stars around anymore most mata in the universe will remain in the form of white and brown dwarves and some mata will persist as neutron stars and black holes it will take a great amount of time for all these objects to cool off around a duodecillion or 10 to the power of 39 years white dwarves will gradually give off their heat in the form of radiation and become black dwarves as for brown dwarves they will cool off too reactions taking place in their interior at a sluggish rate will eventually stop completely gradually most matter will be slurped by black holes at this stage of the universe's evolution dark matter annihilation and protons disintegration will be the major processes the proton is a subatomic particle that atoms known to science are built of it is considered one of the most durable subatomic particles its life expectancy as it were accounts for approximately 100 geodesian or 10 to the power of 41 years now by the time this sierra comes to an end mata in the universe will look like a great ocean of freely floating elementary particles with an occasional neutron star or black hole tucked away among them the next era is the black hole era according to some theories black holes will form clusters and eventually blend together thus forming one single gargantuan black hole alternative theories suggest that black holes will slowly evaporate while emitting energy before vanishing completely black hole evaporation is a quantum effect produced by what is known as hawking radiation the smaller hole the more intense of its evaporation which eventually strips the whole of all its matter and energy this process is supposed to persist for 10 to the power of 100 years this number is also referred to as google be it as it may eventually only dead expanses of space will be left in the universe this space will contain debris left over from processes having taken place in the previous sea parks photons electrons positrons neutrinos and quarks electrons and positrons will collide thus causing annihilation the universe may exist in this state practically forever until the next big crunch or big rip at the very least either way the humanity will be long gone at that time its existence is likely to be terminated in the stelliferous era our planet meanwhile will remain habitable for another billion years or so and after that it will be burned by the ever-intensifying glow of the sun about five or six billion years later our sun by then a red giant will shed its outer layers and become a white dwarf but what will happen after the universe dies disappointing as it is there is absolutely no way we can answer this question the trouble is whatever the scenario there won't be either time or space as we know them even if the big bounce theory or the big crunch theory is right or else a new big bang takes place thus giving birth to a new universe with a fresh set of galaxies and stars we will simply never find out just like we will never find out what it used to be like in the universe before hours because the word must be heard in silence there must be darkness to see the stars it goes without saying that what we've just seen is an infinitely tiny portion of fascinating things out there we could have looked at in this film their number is infinite and it's going to take scientists centuries on end to describe the nature of each of them but even objects we already know of today can be baffling to many scientists yet with information about them regularly updated we will definitely have something exciting to share with you let's keep in touch [Music] you

Channel: Kosmo

Views: 353,666

Rating: 4.7477002 out of 5

Keywords: A JOURNEY, A JOURNEY BEYOND, universe, secrets of the universe, outer space, depths of outer space, cosmos, space, what is hidden in the universe, what is hidden in galaxies, titan, top list of mysterious objects, intergalactic space, microquasar, exoplanet, pluto, the weirdest object in the universe, travelling around the universe, death of the universe, film, video, popular science, science, astronomy, cosmo, kosmo

Id: Cwx9AIncrVQ

Length: 70min 30sec (4230 seconds)

Published: Sun Jan 31 2021