- 1 day ago
Dive into the fascinating world of black holes and the universe! Discover mind-blowing facts about the universe that will leave you in awe of the mysteries of outer space.
Category
😹
FunTranscript
00:00The James Webb Space Telescope is an absolutely stunning piece of equipment,
00:04which is around 100 times more powerful than the Hubble Space Telescope,
00:09and the latter has managed to observe places that are around 13 billion light-years away.
00:14But recently, James Webb has outdone itself.
00:17It spotted something it wasn't supposed to see.
00:20Astronomers using the telescope have detected a supermassive black hole
00:24from when our universe was less than 600 million years old.
00:27Just a baby.
00:29This discovery is the most distant, actively feeding supermassive black ever observed.
00:34It's located at the heart of its host galaxy, designated Sears 1019.
00:39The black hole is also one of the smallest and least massive ones found in the early universe.
00:44It's equal to approximately 9 million suns.
00:47It might seem like a lot, but in reality,
00:50supermassive black holes often grow to billions of times the mass of our star.
00:55But what is so unusual about this find?
00:57And why are scientists having a hard time trying to explain it?
01:01You see, it's supposed to take way longer than 600 million years for a supermassive black hole to grow to
01:07its full potential.
01:09It happens when a black hole either feasts on surrounding matter or merges with a larger black hole.
01:14Even black holes similar to the one at the center of our Milky Way galaxy,
01:18which is almost 4.5 million times the mass of our sun,
01:22are supposed to be seen in the more recent universe.
01:26Well, to tell you the truth, scientists have long suspected that supermassive black holes
01:31could have existed in the early universe.
01:33But this theory has been proven only thanks to the JWST and its infrared eye.
01:38It has shown that the black hole Sears 1019 is actively munching on all the matter it can lay its
01:44hands on.
01:45Such feeding black holes are usually surrounded by swirls of gas and dust falling inside them.
01:51Such swirls are also called accretion disks.
01:54The gravitational force of a black hole heats this matter,
01:57which makes the disk shine bright like a diamond.
02:00Uh-hum.
02:01Sorry, but that's not all.
02:02Strong magnetic fields produced in the process channel the matter to the poles of the black hole,
02:06and from time to time this matter is blasted out of there in twin powerful jets.
02:10They move at a speed that is close to the speed of light, which generates incredibly bright light.
02:16By the way, astronomers were watching the galaxy hosting the unusually old black hole
02:22as part of the cosmic evolution early release since survey.
02:26They saw the galaxy as it was when the universe, which is around 13.8 billion years old now,
02:32was a mere 570 million years old.
02:35Besides the main character of this video, scientists spotted two other black holes.
02:40Those probably appeared 1 in 1.1 billion years after the Big Bang,
02:44and 11 ancient galaxies that existed between 470 and 675 million years after the beginning of cosmic history.
02:53The coolest thing about all these discoveries is that until recently,
02:58all research about things that existed in the early universe was mostly theoretical.
03:02But now, with the help of the James Webb Telescope,
03:05astronomers can not only see galaxies and black holes at unimaginable distances,
03:10but they can also measure them.
03:12This isn't the only discovery connected with black holes made recently.
03:16For example, not so long ago, scientists saw two stars slow down in their orbits around black holes
03:21and concluded it was most likely the result of drag produced by dark matter.
03:26It was the first time astronomers might have discovered some indirect evidence
03:30that huge amounts of dark matter could surround black holes.
03:34Now, about that dark matter.
03:36What is it?
03:37And what does it consist of?
03:39Our universe consists of normal matter, dark matter, and dark energy.
03:43Normal matter, which is everything you can see with your own eyes,
03:46or with the help of instruments,
03:48makes up around 5% of the universe.
03:51Hmm.
03:52Since it's such a small fraction of the universe,
03:55maybe we shouldn't call it normal?
03:57Dark energy takes up around 68%.
04:00And about 27% of the universe is dark matter.
04:04This dark matter is just one more space thing that confuses scientists to no end.
04:10If dark energy is a force responsible for the expansion of the universe,
04:14dark matter is supposed to explain how objects work together.
04:17Potential candidates for dark matter vary from strange particles to super dim objects.
04:23But even though astronomers can't grasp what exactly dark matter is,
04:27they know for sure what it isn't.
04:29This matter is dark, so we can rule out visible stars and planets.
04:33It also can't be dark clouds of normal matter.
04:36Otherwise, scientists would be able to detect it.
04:39Dark matter is not antimatter,
04:41since astronomers don't see unique gamma rays that appear when antimatter comes in contact with matter.
04:46And neither is dark matter gigantic galaxy-sized black holes.
04:50In other words, dark matter is still as much of a mystery to us as dark energy.
04:55Anyway, back to the potential dark matter discovered around the black holes.
05:00If it is confirmed, it'll be a great breakthrough in dark matter research.
05:04What helped scientists come up with this idea,
05:07is that dark matter interacts gravitationally, influencing ordinary matter.
05:12So, a team of researchers watched the orbits of two stars decay by about one millisecond per year,
05:19while they were circling their companion black holes.
05:22The scientists concluded that these changes in speed,
05:25were the result of dark matter generating friction, and a drag on the stars.
05:31With the help of computer simulations of the black hole systems,
05:34the team tested a model widely known in cosmology.
05:38It's called the Dark Matter Dynamic Friction Model,
05:41and it predicts a certain loss of momentum by objects that are gravitationally interacting with dark matter.
05:47And guess what?
05:49The simulation matched these predictions.
05:52The results of this research helped to confirm a theory that had existed for a long time,
05:57that black holes can actually swallow dark matter that comes too close.
06:00As a result, dark matter gets redistributed around black holes,
06:05creating areas with different densities,
06:07which can influence the orbits of surrounding objects,
06:10like the stars we've been talking about.
06:13Speaking of black holes,
06:14there's a theory that primordial black holes could actually be dark matter.
06:18This type of black hole is hypothetical,
06:20since scientists have never got any real proof of their existence.
06:24Such holes are insanely old and quite tiny.
06:27By black hole standards, that is.
06:29Astronomers believe they could appear several milliseconds after the Big Bang.
06:33At that time, stars and galaxies weren't born yet.
06:37It means primordial black holes probably witnessed the entire history of the universe.
06:41By now, the smallest primordial black holes have most likely evaporated away,
06:46but some bigger ones can still be scattered out there in space.
06:50If primordial black holes indeed existed,
06:53they could appear because in some regions of space,
06:55it was hotter,
06:56other regions were cooler,
06:58and some areas were extremely dense.
07:01Scientists believe these dense spots could collapse into primordial black holes.
07:05The most curious thing, though?
07:07These holes might be so small exactly because they popped up right after the Big Bang.
07:11The thing is, the longer it took a black hole to appear, the larger it was.
07:16The mass difference between older, smaller, and younger, bigger black holes was incredible.
07:22Compare the mass a thousand times greater than our suns and that of a pea.
07:25There you go.
07:27Anyway, the idea of the connection between primordial black holes and dark matter,
07:32or rather, the idea of them being the same thing,
07:35remained unpopular for decades.
07:38But recently, scientists have realized there are many more black holes in the universe than they used to think,
07:43and it means that the theory might actually work.
07:46And the vast and still hidden from us,
07:49population of Big Bang black holes,
07:51could not only make up but be dark matter.
07:54After all, astronomers haven't discovered a single dark matter particle yet,
07:59even after decades of searching.
08:02Well, it turns out black holes might not be as elusive as we once thought.
08:07They might be hiding within stars.
08:09In this case, the extra mass of some of these space lanterns
08:13could explain weird gravitational effects in the universe.
08:17Previously, dark matter was the cause of these phenomena.
08:20The black holes I'm talking about
08:22might be those itty-bitty ones that appeared at the dawn of time
08:26when the universe was just a baby.
08:28And they may still be lurking in the hearts of giant stars.
08:32A team of scientists say the idea might be quite plausible.
08:36Astronomers could detect such trapped black holes
08:39by the vibrations they produce on their star's surfaces.
08:42And if there are many of them out there in the cosmos,
08:45they might function as the very dark matter that holds the universe together.
08:51Almost any black hole was once a massive star
08:54that collapsed in on itself and became incredibly dense.
08:58Black holes have immense gravitational pull.
09:01Even light can't escape their clutches.
09:03People often think that black holes work like vacuums,
09:07pulling space inside.
09:08But that's not the case.
09:10Black holes can only swallow stuff that is extremely close,
09:14usually space objects venturing into their event horizon.
09:17That's a black hole's point of no return.
09:20Once you cross this border, there's no escape.
09:24In 1971, renowned physicist Stephen Hawking suggested another origin of black holes.
09:31If we took the thick soup of particles
09:33that appeared moments after the Big Bang and the birth of the universe,
09:37we'd be bound to find some spots dense enough to collapse and create black holes.
09:42Such holes, which got the name of primordial black holes,
09:46could range in size from microscopic to gigantic.
09:50If they were pervasive and numerous enough,
09:53primordial black holes could act as dark matter,
09:56knitting the cosmos together with their enormous gravity.
09:59And dark matter is believed to make up 85% of all the matter in the universe.
10:05So what's the matter?
10:08Astronomers have been searching for primordial holes by looking for flashes
10:12that would occur when they pass in front of distant bright objects,
10:15magnifying their light like a lens.
10:17But they haven't spotted even one yet.
10:20On the other hand, if a primordial black hole was tiny enough,
10:24with a mass like that of an asteroid,
10:26and a diameter as minuscule as a hydrogen atom,
10:29the flashes wouldn't be bright enough to be detected by such surveys.
10:33Then the team, researching the phenomenon of primordial black holes,
10:38decided to consider the consequences of a universe
10:41where dark matter was made entirely out of tiny black holes.
10:45They concluded that one of such teensy holes
10:48could be dashing through the solar system at any given time.
10:51Some might occasionally get trapped within gas clouds,
10:55giving birth to new stars, ending up in their centers.
10:58The next step of the researchers was to build a model of a black hole
11:02existing in the very core of a star,
11:05where hydrogen atoms undergo fusion and produce light and heat.
11:08At first, they didn't see anything unusual.
11:11Even a super-dense stellar core is mostly empty space.
11:15And it wouldn't be easy for a microscopic black hole
11:18to find matter to consume there.
11:20That's why its growth would be incredibly slow.
11:23It could take longer than the lifetime of the universe
11:26for this tiny hole to eat a star.
11:29But what if a larger hole,
11:31as massive as the dwarf planet Pluto or asteroid Ceres,
11:35appeared at the center of a star?
11:37Then it would get bigger in a matter of a few hundred million years.
11:41The material would keep spiraling into the black hole,
11:45creating a disk that would heat up because of friction,
11:48emitting radiation.
11:49Once the black hole grew to the size of Earth,
11:52it would start emitting even more radiation,
11:55shining extremely brightly.
11:56It would also be churning up the star's core.
11:59And the star itself would turn into a black hole-powered
12:03rather than a fusion-powered object.
12:05Such entities were dubbed Hawking stars.
12:09To cool off,
12:10the exterior of a Hawking star would form a red giant.
12:13That's what our sun is likely to turn into as it gets older.
12:17But a red giant star with a primordial black hole at its center
12:21would be cooler than the stars that have reached this stage
12:25through regular means.
12:26Such stars are known as red stragglers.
12:31To find out whether they indeed host a black hole,
12:34astronomers might need to tune into the frequencies at which stars vibrate.
12:38Since a Hawking star would mostly affect the interior of the star
12:42rather than its topmost layers,
12:44the star would thrum with a certain combination of frequencies.
12:48The waves created in the process could be detected in a way the star's light would pulse and throb.
12:54So, all scientists need to do now is study the already known red stragglers
12:59and figure out whether any of them show the characteristic vibrations of a black hole.
13:04Now, should we worry about the sun?
13:07Since our star hasn't reached its red giant stage yet,
13:11we can't know whether it'll turn into a cool red straggler.
13:14What we know, though, is that our star might contain those tiny black holes that formed in the Big Bang.
13:20But now, we have no means to check whether they're indeed there.
13:27Currently, our star is around the midpoint of its existence.
13:31Middle-Aid.
13:32Hmm.
13:33It creates energy non-stop by fusing hydrogen atoms within its core.
13:37Once it runs out of hydrogen in its core,
13:40it will enter its red giant phase and begin to collapse.
13:44It'll happen in about 5 billion years.
13:46Don't hold your breath.
13:47And the phase itself will last for a billion years or so
13:50before our star depletes its fusible materials and loses its outer layers.
13:55It will leave behind a tiny white dwarf star half as massive as the sun
14:00and around the size of our planet.
14:03In some cases, when the gravitational collapse of a star's core is complete,
14:08the star remnants turn into a black hole.
14:11But that's not the fate awaiting our sun.
14:14You see, our star just doesn't have what it takes to become a black hole.
14:18It's not heavy enough.
14:19There are a few conditions that can affect whether a star can turn into a black hole,
14:25including its composition, rotation, and the processes that lead to its evolution.
14:30But the main requirement is still the right mass.
14:34Stars with 20 to 25 times the mass of the sun
14:37can potentially experience the gravitational collapse needed to form black holes.
14:42In other words, the sun is simply too small to form a black hole.
14:46But what would happen to us if it did?
14:51You might assume that if the sun turned into a black hole,
14:55our planet would be doomed to be pulled into it.
14:58But do you remember the basics?
14:59Black holes aren't giant space vacuum cleaners,
15:02just sitting there and waiting for a new planet or star to get their hands on.
15:07But black holes don't have enough gravitational force beyond that created by their incredible mass.
15:13And if the sun were to turn into a black hole, which will not happen,
15:18this hole would still have the same mass as our former star.
15:21And Earth's orbit around this newly formed black hole wouldn't change.
15:25But all other things would change dramatically.
15:29The sun, which is currently around 432,000 miles in radius,
15:34would shrink to a mere 1.9 miles in radius.
15:37But you wouldn't be concerned with the absence of the bright yellow sphere in the sky,
15:42since you have many more pressing issues on your hands.
15:45Our planet's main heat source would be gone, leaving us frozen in the dark.
15:50Without this source of energy, photosynthesis would immediately stop,
15:54disrupting entire food chains.
15:56Eventually, all life on Earth would be extinguished.
15:59But rest assured, our hard, barren rock of a planet would continue in its orbit.
16:05Oh well.
Comments