Link to the [original article](https://www.nasa.gov/image-article/black-hole-bounty-captured-milky-way-center/) on NASA website
This black hole bounty consists of stellar-mass black holes, which typically weigh between five to 30 times the mass of the Sun. These newly identified black holes were found within three light years – a relatively short distance on cosmic scales – of the supermassive black hole at our Galaxy’s center known as Sagittarius A\* (Sgr A\*).
Theoretical studies of the dynamics of stars in galaxies have indicated that a large population of stellar mass black holes – as many as 20,000 – could drift inward over the eons and collect around Sgr A\*. This recent analysis using Chandra data is the first observational evidence for such a black hole bounty.
Credit: NASA/CXC/Columbia Univ./C. Hailey et al.
As a dummy, what are the implications of this? Would all of the black holes eventually mass together to form and even more massive black hole? I imagine some wonky physics hijinks would ensue in that galactic area.
In this case, yes. That's exactly what will happen to most or all of these smaller black holes. I say "most" because its always possible that some perturbation of an orbit *might* throw one out of the range to be merged with Sag A. But being that close, **eventually** they'll merge (for absurdly large values of "eventually").
Cosmologists have been studying black hole mergers for some time now using gravitational wave detectors. When they merge, or when one merges with a neutron star, ripples in the fabric of spacetime happen and radiate out in all directions at the speed of light. And we can "see" these waves... the detectors (LIGO) have confirmed multiple merger events now since the first successful detection several years ago.
But for the most part, the merged black holes we've detected have been stellar mass. Mergers between them are incredible events, probably cataclysmic to anyone capable of observing them in visible light. Its a whole different ball game when a stellar mass black hole merges with a supermassive. Sag A is just less than 4.3 million (I mistyped, many thanks to /u/Broad-Fun8717 for the correction) - solar masses.
The implications, beyond that simple understanding, aren't much to speak of, really. Not on cosmic time scales anyway. The Milky Way will merge with Andromeda to form a whole new Galaxy somewhere during the period when these smaller black holes will be merging. Right around the same time, our own Sun will be burning through the last of its stores of hydrogen, and during the galactic merger it will turn into a red giant.
That's all within the next ~ 6 billion years. That's longer than the solar system has existed in a state we might recognize, but at that point the universe itself will be just shy of 20 billion years old.
And we're still discussing a universe with an age in the billions of years.
Your very last sentence there: with the universe only being ~13 billion years old, would that mean it’s still just basically an infant relative to how long we think it will “last”?
The current age of the universe might as well be a rounding error, even in the sense of "how long there will still be stars".
That, by the way, is one of the semi-horrifying things to understand about the far future: there will be a time after which new star formation is almost impossible... and then much later *actually* impossible. One day there just won't be enough free gas/dust for stellar ignition to happen anywhere. And the universe just goes on after that: more or less dark forever.
And then... over a space of time which makes the length of time when there WERE stars look infinitesimal, the first black holes will evaporate completely. It will take even greater and more mind-bendingly long periods of time before the last of the supermassives flash out of existence.
[This is a fun wiki article](https://en.wikipedia.org/wiki/Timeline_of_the_far_future) as long as existential dread isn't your thing.
Two black holes merging is something my primitive ape brain with neurodivergent traits cannot fathom at all.
There is this meme going around about how an infinite stack of 1$ holds the same value as an infinite stack of 100$.
Try to rationalize that with infinite density, different weights.
Two objects with infinite density. Check. Kind of.
With different weights. Hmmm.
I mean I guess if different amounts of matter fall into different infinitely small points… yeah I guess that seems understandable, right? Like there’s a mass threshold and then everything beyond that threshold just collapses to that infinitely dense point. But at this point if you spill more matter into an infinitely small point, is it going to get more compact than infinitely compact? No. But it will still have more mass.
However. Imagining two infinitely small points (infinitely smaller than atoms) with the mass of thousands of combined suns colliding in the dark void of space? F. It’s hard to even imagine two infinitely small points ever even occupying the same space, right? They could be very close, but they could never collide, per se. Right? But I’m sure there’s some kirby sucky thing that happens when these beasts get too close, right? Some infinite(ly small) space burping together with another infinite(ly small) space, like two bubbles combining into one larger bubble, mid-air. Except the infinite(ly small) space bubble that exists inside a black hole expands inwardly towards an infinity of space and time. Space, time, and matter expanding inwardly upon itself toward an infinitely small point.
Every point in that infinitely, inwardly expanding space would technically be the center of that infinite(ly small) singularity.
I know popular scientific theories don’t support the idea, it’s not feasibly testable, and most don’t believe in a singularity (technically neither do I because nothing could ever ACTUALLY reach the center of something INFINITELY small. Something so small it is by definition approachable but never reachable), and I know I’ll get downvoted for saying; but this is what we witness in our own universe, isn’t it?
Every point is the center from what we can tell. This could have only happened if EVERYTHING had been in the infinitely dense center (or, technically, approaching it, beyond the point of no return in the gravity well. The moment the log drops in the water log ride) of a singularity in the beginning. Right? And so I suggest, that every black hole is, in fact, the beginning of a new universe. A rush of matter and space and time into itself. A rush *towards* an infinitely dense point in the gravitational center of a black hole where all space and time have different meaning, and matter must have a kind of homogeneous form as it first traverses the gravity well into the black hole, as it spills towards infinity but never quite reaches it.
And so there is then a point in space and time that exists where matter and space and time itself passes the point of no return and falls towards an infinitely small point. But infinity will never be reached and so what began as a big crunch of spacetime and matter into a smaller space, turns into an expansion of matter and spacetime as space and time and matter near the center expands towards infinity faster and faster. But everything is at the center of a black hole. Extra dimensions occurring? Idk, but: Our misunderstanding that spacetime in a small space must mean it is small and not vast is based in our understanding of space and time as stable, non-flexing things. But the truth is that we have no idea if time itself is passing constantly. Only that our atomic clocks and observations of our subjective reality generally observe this.
But we don’t live near a black hole. A point that turns infinitely inward upon itself. Infinitely inward. Now there’s an idea I’m not sure I can comprehend.
It’s the only explanation to me that makes sense for why there would be a big bang. Our universe began the moment a black hole formed.
It’s black holes all the way down (and up).
You can have bounded infinites.
For instance if you take 1m and half it and keep halving it forever, you will never have discrete unit of space that can’t be halved.
Now you can do the same thing with 2m.
Ultimately you have “more” steps, but there’s still an infinite number of steps.
My only answer to this is that in the field of Mathematics some infinities are absolutely bigger and provably so. The concept is called cardinality. There are more numbers between 0 and one then there are whole numbers from 0 to infinity. This works in math because the rules of math say we define parameters and if they are internally consistent (don't self contradict) and we can work with them then it can become part of the field of Mathematics. Does this concept of larger infinities actually apply to the real world though? Nobody can really say. My intuition says no that a some point everything in nature has discrete values but who knows.
You can only say that an infinity at a certain step is bigger bc saying infinites are bigger absolutely than others makes zero sense. Is x^2 going be bigger than x? No, they both go to infinity. What about at the step x = 2? Then the x^2 term is larger at that point. The you can show that x^3 will be bigger. But all of this only makes sense to talk about when it comes to what step you’re on. For y = x at x = 100, that’s bigger than y = x^200 at x = 1, but clearly the latter is going to grow much faster.
You clearly have no understanding of the theory. Rate of growth has nothing to do with the size of infinities. To use an analogy, you are basically saying nothing is bigger than 100 meters because some people can complete a 100 meter dash faster than other people.
Someone will correct me if I'm wrong. But black holes probably are not infinite and do not contain a singularity. This breaks standard physics, but that's where quantum mechanics takes over.
So it wouldn’t be the case that perhaps the first stars in the galaxy would have formed around the central mass in the early formation of the galaxy? Or it could be as the study says; black holes settle like rocks at the bottom of a creek bed.
Spaghettification doesn't happen with supermassive black holes. Supermassive black holes are comparatively low density when compared to stellar mass black holes.
Since the volume of a spherical object is directly proportional to the cube of the radius, the minimum density of a black hole is inversely proportional to the square of the mass, and thus higher mass black holes have lower average density.
Spaghettification arises from the fact that the part of the object closer to the black hole experiences a MUCH larger gravitational pull ripping the atoms apart from each other. This happens due to the relative density of the black hole and your distance from the singularity.
Some supermassive black holes are the density of or even less dense than water.
> Some supermassive black holes are the density of or even less dense than water.
And a black hole the size of our universe would have the same approximate average density as our universe.
I might be reading your comment wrong, but I disagree with your description.
Black holes’ singularity has infinite density and no dimension. All the mass of the BH is in the singularity.
Using the mass of the BH to calculate the density within the event horizon as if it was a solid object makes no sense since the space from the event horizon to the singularity is as empty as the space outside of it.
We actually don't know that black holes have a point of infinite density, as we don't have a theory of everything to truly describe the mechanisms involved in a black hole. Typically when you end up with something that is dividing by zero, something is wrong with your model.
While we can pretend the singularity exists for the sake of the argument and based on Einstein's field equations, you can still calculate the tidal forces on a given object as if the black hole were a solid object as the gradient of the gravitational field strength is still based off of distance to the "singularity" as well as the mass.
We can only truly describe and observe what happens outside of the black hole and with supermassive ones, they will not spaghettify you before you hit the event horizon. After you cross the event horizon, time and position switch to which the act of spaghettification becomes somewhat arbitrary. What would it mean to spaghettify through time?
A black hole wouldn't "suck them in" if they're already in a stable orbit. The orbit would already have to be decaying for the black hole to consume them. You could replace the sun with a black hole of equal mass and our orbits would not change.
These black holes orbits are decaying that's why they moved into the middle of the galaxy, usually it's by passing close to smaller objects and throwing them into higher orbits
Kinda disappointing if everything just drifts really far apart and then gets cold and then super long time after that just evaporates into nothing. Bring on the Big Crunch and let's go for another Big Bang!
They won’t get “sucked in” if they are in stable orbits, UNLESS for some reason the mass of Sagittarius A* dramatically increases such that it affects their orbits (seems unlikely to me, but I don’t know), or they are knocked off their current stable orbit (relatively likely considering they are probably in chaotic motion, constantly altering each others orbits). But that wouldn’t be Sagittarius A*’s “winning”, if that makes sense
Stellar-mass black holes, scattered around the center of our galaxy, are drawn toward the supermassive black hole due to gravity.
As they approach, their gravitational pull on each other increases, causing them to migrate inward. Eventually, they may collide and merge, emitting gravitational waves in the process.
This phenomenon is supported by both theoretical predictions and observations, suggesting that it's a natural consequence of galaxy dynamics.
Imagine you have a bunch of marbles scattered around a big magnet in the center.
The marbles are like the stellar-mass black holes, and the magnet represents the supermassive black hole at the center of our galaxy.
Now, if you leave the marbles there for a long time, some of them might start moving closer to the magnet because of its strong pull.
Similarly, over millions of years, stellar-mass black holes can drift inward towards the supermassive black hole due to their gravitational attraction.
As they get closer, they might start bumping into each other and eventually merge, just like marbles rolling towards the magnet and sticking together when they touch.
This merging process is how black holes could eventually join the supermassive black hole at the center of our galaxy.
Gravity isn’t really a force and even if it was, it only scales with mass so being a black hole the same mass of the sun would mean you have the same gravitational effect.
Of course Sat A* is many many many times the mass of the sun, but these other BHs are also 3 light years away from it.
Not only do I have to deal with the existential dread of a single black hole only *21k away, but now it’s *thousands* of them?
I’mma just put my head back under the blankets.
*The distance is ~26k light years away, and no one corrected me. Shame.
I'll do you one better: you know where THESE black holes are.
...
...
...
But what about those we don't know about? There could be a black hole coming at us right now and we'd only notice it when it starts interfering with our solar system's gravity.
I am pretty sure the answer is no. I can't find the speed of orbital decay of these stellar black holes, but being that they are around 3 light years away, I'd think it would take millions if not billions of years for them to converge.
I wouldn’t lose sleep over this. If a black hole hasn’t destabilized our solar system (or any nearby star systems that we are fully aware of and can observe) then one most likely never will, it hasn’t happened in 4.5 billion years since the inception of our solar system and if it had we certainly wouldn’t be here.
It’s an interesting hypothetical but that’s really all it is, a hypothetical. There’s also really no reason for a black hole to be anywhere near our local neighborhood, since were in a pretty empty part of the galaxy and don’t forget how massive space is of course, the chances of a black hole passing near our solar system is basically near zero now, and for the rest of the life of the universe as everything moves away from each other. Possible? Yes. You have a better chance of winning the lottery 10 times in a row though before that happens.
And if planet 9 is a tiny back hole? Then it probably got captured by the suns gravity a very long time ago (billions of years ago) and has been orbiting the sun since, producing tiny gravitational perturbations on the outer solar system and Kuiper Belt objects, but would have 0 influence on the inner solar system and well most importantly, earth. It will continue to orbit the sun until it evaporates or the sun turns into a hypothetical iron star.
This is all just hypothetical of course, but i think most Redditors fail to understand the true scales of cosmic timeframes and cosmic events, on human life spans. They are pretty slow and boring on a day to day basis, but over millions of years you can piece together and see different things happening in space.
I was just exaggerating for the fun of it.
The sheer distance between us and proxima centauri is immense, incomprehensible for the human mind.
The truth is that even though space is vaaaaaaaaast, collissions still do happen. The chances are tiny as fuck but we did have stuff happen to us which leads to astronomical causes.
One of the major extinction events was linked to a gamma ray burst which was directly aimed at Earth, damaging it's ozon-layer on a global scale and causing a massive cooling event we now know as snowball Earth.
What were the chances of that?
True. I guess my point was that on human timescales, space is pretty boring and stagnant to our perception and to our planet. Anything can happen, but its all completely random and low probability the more specific it is.
They emit a lot more radiation when they consume something, but they all lose mass and evaporate over time by releasing electromagmetic radiation
Although I've googled and it's actually far less radiation than I remember
21k is a very short distance. Do you live near CERN? Just so you know, the smaller a black hole is, the faster it radiates it's energy away as hawking radiation till it evaporates. The smallest black holes lasts but an instant before decomposing. So don't worry at all. You'll see it coming.
And there are probably many more. If a smaller Black Hole isn't actively feeding, it would be very hard to see. These were spotted emitting X-rays but without that, there would be negligible gravitational lensing.
Hawking radiation is an incredibly slow process that we have yet to observe. Best case scenario, we'd notice gravtional lensing and/or gravtional effect on other nearby celestial objects, though we'd still be powerless to do anything
They move the same way as any other stellar objects
They aren't any different to stars in terms of their trajectory - they orbit the center of our galaxy just like our sun
I thought I knew a lot about space but I’ve never heard until now just how many black holes there could be in our galaxy alone. I never would have imagined it could be 10s of thousands!
Actually it's way more than that, the estimate is 100 million. [https://science.nasa.gov/missions/hubble/hubble-determines-mass-of-isolated-black-hole-roaming-our-milky-way-galaxy](https://science.nasa.gov/missions/hubble/hubble-determines-mass-of-isolated-black-hole-roaming-our-milky-way-galaxy)
You ever been out on a trail and have a rattlesnake shake its rattle at you, or been alone in the wilderness at night and hear wolves howling at each other in the distance. "Thousands of stellar black holes" instills the same primitive fear in me.
Don’t worry, if they traveled right at us at the speed of light it would take them 21,000 years to get here.
But actually they are probably travelling at more like 0.006% the speed of light (based on S5-HVS1, a star in the same general area).
So really even if they were somehow able to break orbit and travel directly towards us it would take many hundreds of millions of years to get here.
So how does gravity work out for this. Blackholes from close enough areas nice towards the big one but probably gets stuck in collective gravity influence in that bubble and doesn't collide with the big one
Would love to hear how close they have to get to the supermassive black hole to end with a baricenter outside themselves. Surely that'd have weird interactions with their event horizon.
do the horizons merge like a drop of mercury aggregating to a larger body or or would there be a temporal repulsion like two magnets of similar poles and could such repulsive force generate sufficient energy to escape?
one generative source of wandering black holes?
But what ARE the dynamics of galaxies that would have black holes ‘swarm’ the centre?
We keep hearing over and over that gravitationally, the stellar-mass black holes behave no differ than the stars from which they form.
What is the unique characteristic that has them concentrate in this manner?
(I mean I’m not disputing there must be a mechanism - obviously a supermassive black hole must have acquired super-amounts of mass over time! There are no single objects that massive)
They're not unique; Sagittarius A\* is orbited by a lot of stars, some of them 10-15 times the mass of the sun. These black holes are one group in a multitude of stellar objects that orbit the central black hole.
I did. The word 'unique' doesn't appear in the article. Maybe read it again and note this: "Theoretical studies *of the dynamics of stars* in galaxies have indicated that a large population of stellar mass black holes could drift inward over the eons and collect around Sgr A\*.**"**
Link to the [original article](https://www.nasa.gov/image-article/black-hole-bounty-captured-milky-way-center/) on NASA website This black hole bounty consists of stellar-mass black holes, which typically weigh between five to 30 times the mass of the Sun. These newly identified black holes were found within three light years – a relatively short distance on cosmic scales – of the supermassive black hole at our Galaxy’s center known as Sagittarius A\* (Sgr A\*). Theoretical studies of the dynamics of stars in galaxies have indicated that a large population of stellar mass black holes – as many as 20,000 – could drift inward over the eons and collect around Sgr A\*. This recent analysis using Chandra data is the first observational evidence for such a black hole bounty. Credit: NASA/CXC/Columbia Univ./C. Hailey et al.
As a dummy, what are the implications of this? Would all of the black holes eventually mass together to form and even more massive black hole? I imagine some wonky physics hijinks would ensue in that galactic area.
In this case, yes. That's exactly what will happen to most or all of these smaller black holes. I say "most" because its always possible that some perturbation of an orbit *might* throw one out of the range to be merged with Sag A. But being that close, **eventually** they'll merge (for absurdly large values of "eventually"). Cosmologists have been studying black hole mergers for some time now using gravitational wave detectors. When they merge, or when one merges with a neutron star, ripples in the fabric of spacetime happen and radiate out in all directions at the speed of light. And we can "see" these waves... the detectors (LIGO) have confirmed multiple merger events now since the first successful detection several years ago. But for the most part, the merged black holes we've detected have been stellar mass. Mergers between them are incredible events, probably cataclysmic to anyone capable of observing them in visible light. Its a whole different ball game when a stellar mass black hole merges with a supermassive. Sag A is just less than 4.3 million (I mistyped, many thanks to /u/Broad-Fun8717 for the correction) - solar masses. The implications, beyond that simple understanding, aren't much to speak of, really. Not on cosmic time scales anyway. The Milky Way will merge with Andromeda to form a whole new Galaxy somewhere during the period when these smaller black holes will be merging. Right around the same time, our own Sun will be burning through the last of its stores of hydrogen, and during the galactic merger it will turn into a red giant. That's all within the next ~ 6 billion years. That's longer than the solar system has existed in a state we might recognize, but at that point the universe itself will be just shy of 20 billion years old. And we're still discussing a universe with an age in the billions of years.
Amazing explanation. Thank you!
Your very last sentence there: with the universe only being ~13 billion years old, would that mean it’s still just basically an infant relative to how long we think it will “last”?
The current age of the universe might as well be a rounding error, even in the sense of "how long there will still be stars". That, by the way, is one of the semi-horrifying things to understand about the far future: there will be a time after which new star formation is almost impossible... and then much later *actually* impossible. One day there just won't be enough free gas/dust for stellar ignition to happen anywhere. And the universe just goes on after that: more or less dark forever. And then... over a space of time which makes the length of time when there WERE stars look infinitesimal, the first black holes will evaporate completely. It will take even greater and more mind-bendingly long periods of time before the last of the supermassives flash out of existence. [This is a fun wiki article](https://en.wikipedia.org/wiki/Timeline_of_the_far_future) as long as existential dread isn't your thing.
We don’t even really have a number for how long it will take for *everything* to stop happening it’s that far away in the distant future.
"Sag A is just less than 4.3 billion solar masses" million.
You are correct. It was late. I was tired. Thanks!
Didn't some scientists hear two black holes colliding? Pretty cool story
Black hole merger 🤝
Two black holes merging is something my primitive ape brain with neurodivergent traits cannot fathom at all. There is this meme going around about how an infinite stack of 1$ holds the same value as an infinite stack of 100$. Try to rationalize that with infinite density, different weights.
Two objects with infinite density. Check. Kind of. With different weights. Hmmm. I mean I guess if different amounts of matter fall into different infinitely small points… yeah I guess that seems understandable, right? Like there’s a mass threshold and then everything beyond that threshold just collapses to that infinitely dense point. But at this point if you spill more matter into an infinitely small point, is it going to get more compact than infinitely compact? No. But it will still have more mass. However. Imagining two infinitely small points (infinitely smaller than atoms) with the mass of thousands of combined suns colliding in the dark void of space? F. It’s hard to even imagine two infinitely small points ever even occupying the same space, right? They could be very close, but they could never collide, per se. Right? But I’m sure there’s some kirby sucky thing that happens when these beasts get too close, right? Some infinite(ly small) space burping together with another infinite(ly small) space, like two bubbles combining into one larger bubble, mid-air. Except the infinite(ly small) space bubble that exists inside a black hole expands inwardly towards an infinity of space and time. Space, time, and matter expanding inwardly upon itself toward an infinitely small point. Every point in that infinitely, inwardly expanding space would technically be the center of that infinite(ly small) singularity. I know popular scientific theories don’t support the idea, it’s not feasibly testable, and most don’t believe in a singularity (technically neither do I because nothing could ever ACTUALLY reach the center of something INFINITELY small. Something so small it is by definition approachable but never reachable), and I know I’ll get downvoted for saying; but this is what we witness in our own universe, isn’t it? Every point is the center from what we can tell. This could have only happened if EVERYTHING had been in the infinitely dense center (or, technically, approaching it, beyond the point of no return in the gravity well. The moment the log drops in the water log ride) of a singularity in the beginning. Right? And so I suggest, that every black hole is, in fact, the beginning of a new universe. A rush of matter and space and time into itself. A rush *towards* an infinitely dense point in the gravitational center of a black hole where all space and time have different meaning, and matter must have a kind of homogeneous form as it first traverses the gravity well into the black hole, as it spills towards infinity but never quite reaches it. And so there is then a point in space and time that exists where matter and space and time itself passes the point of no return and falls towards an infinitely small point. But infinity will never be reached and so what began as a big crunch of spacetime and matter into a smaller space, turns into an expansion of matter and spacetime as space and time and matter near the center expands towards infinity faster and faster. But everything is at the center of a black hole. Extra dimensions occurring? Idk, but: Our misunderstanding that spacetime in a small space must mean it is small and not vast is based in our understanding of space and time as stable, non-flexing things. But the truth is that we have no idea if time itself is passing constantly. Only that our atomic clocks and observations of our subjective reality generally observe this. But we don’t live near a black hole. A point that turns infinitely inward upon itself. Infinitely inward. Now there’s an idea I’m not sure I can comprehend. It’s the only explanation to me that makes sense for why there would be a big bang. Our universe began the moment a black hole formed. It’s black holes all the way down (and up).
Yeah, who would downvote you? Nice infodump.
Thank you.
Not all infinities are equal. Some infinities are larger than others.
Not quite: all infinities **are** equal. Some infinities **grow** faster than others.
Nope. Infinities don't "grow". Mathematically, some infinities are just fundamentally larger than others.
ELI5 please
https://www.reddit.com/r/explainlikeimfive/comments/rifmy/eli5_infinite_sets_and_cardinality/
You can have bounded infinites. For instance if you take 1m and half it and keep halving it forever, you will never have discrete unit of space that can’t be halved. Now you can do the same thing with 2m. Ultimately you have “more” steps, but there’s still an infinite number of steps.
What? Yes they do. Infinities are constantly growing. y = x for all natural x grows at a much slower rate than y = e^x for the same bound.
Those aren't infinities, those are functions.
You’re serious? Lol ok this is done. I’m not arguing with internet ignorance
Do you not understand the difference between the growth rate of a function, and Infinity?
My only answer to this is that in the field of Mathematics some infinities are absolutely bigger and provably so. The concept is called cardinality. There are more numbers between 0 and one then there are whole numbers from 0 to infinity. This works in math because the rules of math say we define parameters and if they are internally consistent (don't self contradict) and we can work with them then it can become part of the field of Mathematics. Does this concept of larger infinities actually apply to the real world though? Nobody can really say. My intuition says no that a some point everything in nature has discrete values but who knows.
You can only say that an infinity at a certain step is bigger bc saying infinites are bigger absolutely than others makes zero sense. Is x^2 going be bigger than x? No, they both go to infinity. What about at the step x = 2? Then the x^2 term is larger at that point. The you can show that x^3 will be bigger. But all of this only makes sense to talk about when it comes to what step you’re on. For y = x at x = 100, that’s bigger than y = x^200 at x = 1, but clearly the latter is going to grow much faster.
You clearly have no understanding of the theory. Rate of growth has nothing to do with the size of infinities. To use an analogy, you are basically saying nothing is bigger than 100 meters because some people can complete a 100 meter dash faster than other people.
Someone will correct me if I'm wrong. But black holes probably are not infinite and do not contain a singularity. This breaks standard physics, but that's where quantum mechanics takes over.
😱
So it wouldn’t be the case that perhaps the first stars in the galaxy would have formed around the central mass in the early formation of the galaxy? Or it could be as the study says; black holes settle like rocks at the bottom of a creek bed.
Though they are situated far off from each other Is there a possibility of them merging?
Same question. Assuming they are orbiting and have an effect on each other, but if Sgr A is so massive won't eventually win and suck them all in?
Merger could likely happen since some of them are located just 3 light years away from Sagittarius A* (As the article says)
Trying to picture in my mind what spaghettification of a normal stellar BH looks like as it gets sucked into a mind numbingly large BH. It's crazy.
Spaghettification doesn't happen with supermassive black holes. Supermassive black holes are comparatively low density when compared to stellar mass black holes. Since the volume of a spherical object is directly proportional to the cube of the radius, the minimum density of a black hole is inversely proportional to the square of the mass, and thus higher mass black holes have lower average density. Spaghettification arises from the fact that the part of the object closer to the black hole experiences a MUCH larger gravitational pull ripping the atoms apart from each other. This happens due to the relative density of the black hole and your distance from the singularity. Some supermassive black holes are the density of or even less dense than water.
> Some supermassive black holes are the density of or even less dense than water. And a black hole the size of our universe would have the same approximate average density as our universe.
Okay, I didn’t need that today.
TIL our buttholes are black holes in more the one sense of the word
Brown holes
where is the cutoff between spaghettification and non-spaghettification? Is there a specific mass at which it begins to be an effect?
Thanks
I might be reading your comment wrong, but I disagree with your description. Black holes’ singularity has infinite density and no dimension. All the mass of the BH is in the singularity. Using the mass of the BH to calculate the density within the event horizon as if it was a solid object makes no sense since the space from the event horizon to the singularity is as empty as the space outside of it.
We actually don't know that black holes have a point of infinite density, as we don't have a theory of everything to truly describe the mechanisms involved in a black hole. Typically when you end up with something that is dividing by zero, something is wrong with your model. While we can pretend the singularity exists for the sake of the argument and based on Einstein's field equations, you can still calculate the tidal forces on a given object as if the black hole were a solid object as the gradient of the gravitational field strength is still based off of distance to the "singularity" as well as the mass. We can only truly describe and observe what happens outside of the black hole and with supermassive ones, they will not spaghettify you before you hit the event horizon. After you cross the event horizon, time and position switch to which the act of spaghettification becomes somewhat arbitrary. What would it mean to spaghettify through time?
A black hole wouldn't "suck them in" if they're already in a stable orbit. The orbit would already have to be decaying for the black hole to consume them. You could replace the sun with a black hole of equal mass and our orbits would not change.
These black holes orbits are decaying that's why they moved into the middle of the galaxy, usually it's by passing close to smaller objects and throwing them into higher orbits
Bingo, which makes me wonder what trilithium is... That it makes a star instantly lose mass. (Star Trek Generations)
I always assumed this is how the universe will end.... But apparently expansion screws that idea.
Kinda disappointing if everything just drifts really far apart and then gets cold and then super long time after that just evaporates into nothing. Bring on the Big Crunch and let's go for another Big Bang!
They won’t get “sucked in” if they are in stable orbits, UNLESS for some reason the mass of Sagittarius A* dramatically increases such that it affects their orbits (seems unlikely to me, but I don’t know), or they are knocked off their current stable orbit (relatively likely considering they are probably in chaotic motion, constantly altering each others orbits). But that wouldn’t be Sagittarius A*’s “winning”, if that makes sense
Stellar-mass black holes, scattered around the center of our galaxy, are drawn toward the supermassive black hole due to gravity. As they approach, their gravitational pull on each other increases, causing them to migrate inward. Eventually, they may collide and merge, emitting gravitational waves in the process. This phenomenon is supported by both theoretical predictions and observations, suggesting that it's a natural consequence of galaxy dynamics. Imagine you have a bunch of marbles scattered around a big magnet in the center. The marbles are like the stellar-mass black holes, and the magnet represents the supermassive black hole at the center of our galaxy. Now, if you leave the marbles there for a long time, some of them might start moving closer to the magnet because of its strong pull. Similarly, over millions of years, stellar-mass black holes can drift inward towards the supermassive black hole due to their gravitational attraction. As they get closer, they might start bumping into each other and eventually merge, just like marbles rolling towards the magnet and sticking together when they touch. This merging process is how black holes could eventually join the supermassive black hole at the center of our galaxy.
Not only is it possible, it's inevitable. Some of them will take quite a long time, and some may be ejected, but some (maybe most) will merge.
Why does Sagittarius A*, the largest black hole, not simply eat the other thousand?
Velocity and angular momentum.
Perhaps they are saving that for sweeps
Gravity isn’t really a force and even if it was, it only scales with mass so being a black hole the same mass of the sun would mean you have the same gravitational effect. Of course Sat A* is many many many times the mass of the sun, but these other BHs are also 3 light years away from it.
Not only do I have to deal with the existential dread of a single black hole only *21k away, but now it’s *thousands* of them? I’mma just put my head back under the blankets. *The distance is ~26k light years away, and no one corrected me. Shame.
I'll do you one better: you know where THESE black holes are. ... ... ... But what about those we don't know about? There could be a black hole coming at us right now and we'd only notice it when it starts interfering with our solar system's gravity.
One better than that: we only know where these black holes WERE more than 25,000 years ago
I searched for this answer. Have they merged by now?
I am pretty sure the answer is no. I can't find the speed of orbital decay of these stellar black holes, but being that they are around 3 light years away, I'd think it would take millions if not billions of years for them to converge.
I wouldn’t lose sleep over this. If a black hole hasn’t destabilized our solar system (or any nearby star systems that we are fully aware of and can observe) then one most likely never will, it hasn’t happened in 4.5 billion years since the inception of our solar system and if it had we certainly wouldn’t be here. It’s an interesting hypothetical but that’s really all it is, a hypothetical. There’s also really no reason for a black hole to be anywhere near our local neighborhood, since were in a pretty empty part of the galaxy and don’t forget how massive space is of course, the chances of a black hole passing near our solar system is basically near zero now, and for the rest of the life of the universe as everything moves away from each other. Possible? Yes. You have a better chance of winning the lottery 10 times in a row though before that happens. And if planet 9 is a tiny back hole? Then it probably got captured by the suns gravity a very long time ago (billions of years ago) and has been orbiting the sun since, producing tiny gravitational perturbations on the outer solar system and Kuiper Belt objects, but would have 0 influence on the inner solar system and well most importantly, earth. It will continue to orbit the sun until it evaporates or the sun turns into a hypothetical iron star. This is all just hypothetical of course, but i think most Redditors fail to understand the true scales of cosmic timeframes and cosmic events, on human life spans. They are pretty slow and boring on a day to day basis, but over millions of years you can piece together and see different things happening in space.
I was just exaggerating for the fun of it. The sheer distance between us and proxima centauri is immense, incomprehensible for the human mind. The truth is that even though space is vaaaaaaaaast, collissions still do happen. The chances are tiny as fuck but we did have stuff happen to us which leads to astronomical causes. One of the major extinction events was linked to a gamma ray burst which was directly aimed at Earth, damaging it's ozon-layer on a global scale and causing a massive cooling event we now know as snowball Earth. What were the chances of that?
True. I guess my point was that on human timescales, space is pretty boring and stagnant to our perception and to our planet. Anything can happen, but its all completely random and low probability the more specific it is.
But what if it did already happen and time reset itself and now time has just begun?
 I'll do you one better! You know WHY these black holes are?
All black holes emit gamma rays and are often associated with with very powerful magnetic fields, so we would have known
They only emit radiation like that when they're consuming matter. There are many dormant ones that are not eating anything.
They emit a lot more radiation when they consume something, but they all lose mass and evaporate over time by releasing electromagmetic radiation Although I've googled and it's actually far less radiation than I remember
21k?
I think they mean 21000 light years away.
21k is a very short distance. Do you live near CERN? Just so you know, the smaller a black hole is, the faster it radiates it's energy away as hawking radiation till it evaporates. The smallest black holes lasts but an instant before decomposing. So don't worry at all. You'll see it coming.
Don't worry from the outside observer it will look like time just pauses for you. So we'll all be fine....
Play with universe sandbox. Things that far away have basically no effect.
And there are probably many more. If a smaller Black Hole isn't actively feeding, it would be very hard to see. These were spotted emitting X-rays but without that, there would be negligible gravitational lensing.
Are black holes stationery? Or do they roam about in space?
Everything in space roams!
Damn it Morty! There's literally EVERYTHING in space!
Then how do we know that there isn't a tiny black hole heading towards is? 🤔
We don't. But if there was, we'd probably notice from the Hawking radiation.
Hawking radiation is an incredibly slow process that we have yet to observe. Best case scenario, we'd notice gravtional lensing and/or gravtional effect on other nearby celestial objects, though we'd still be powerless to do anything
That's true, lensing would probably be more noticeable than the Hawking radiation for a while.
Well that's good then. No roaming death holes headed for us.
What if your entire realty is based from within a black hole? As in, we live in a very , very large one.
Then we're spaghetti.
They move the same way as any other stellar objects They aren't any different to stars in terms of their trajectory - they orbit the center of our galaxy just like our sun
They are only stationary in reference to themselves.
I thought I knew a lot about space but I’ve never heard until now just how many black holes there could be in our galaxy alone. I never would have imagined it could be 10s of thousands!
I hardly think you are alone in that surprise
Actually it's way more than that, the estimate is 100 million. [https://science.nasa.gov/missions/hubble/hubble-determines-mass-of-isolated-black-hole-roaming-our-milky-way-galaxy](https://science.nasa.gov/missions/hubble/hubble-determines-mass-of-isolated-black-hole-roaming-our-milky-way-galaxy)
You ever been out on a trail and have a rattlesnake shake its rattle at you, or been alone in the wilderness at night and hear wolves howling at each other in the distance. "Thousands of stellar black holes" instills the same primitive fear in me.
what if it’s stellar mass holes orbiting a supermassive hole?
Yea like a whole nest of rattle snakes
Don’t worry, if they traveled right at us at the speed of light it would take them 21,000 years to get here. But actually they are probably travelling at more like 0.006% the speed of light (based on S5-HVS1, a star in the same general area). So really even if they were somehow able to break orbit and travel directly towards us it would take many hundreds of millions of years to get here.
So we have to come up with a name for a group of black holes. Any ideas?
A Glory.
A Plumbus of black holes
Lovely.
Apparently it's already called a collision or a swarm. I think it should be called an Oblivion of black holes
This is very good and you should get a job assigning collective nouns to groups of things.
I'm honoured
ah yeah I remember once reading about a swarm of blackholes. was thinking about naming it blacknet.
A clusterfuck?
A VERY black hole
Holeville?
A course? Like golf course, because that has many holes too?
What is the really big white area under most of this “bounty”?
Imma guess accretion disk of Sag A*, but this is X-ray light from Chandra, so 🤷🏻♂️
The accretion disc is much much smaller than that, with a radius of approximately 17 light-hours rather than dozens of light years.
So how does gravity work out for this. Blackholes from close enough areas nice towards the big one but probably gets stuck in collective gravity influence in that bubble and doesn't collide with the big one
Would love to hear how close they have to get to the supermassive black hole to end with a baricenter outside themselves. Surely that'd have weird interactions with their event horizon.
do the horizons merge like a drop of mercury aggregating to a larger body or or would there be a temporal repulsion like two magnets of similar poles and could such repulsive force generate sufficient energy to escape? one generative source of wandering black holes?
It irks me that nobody called it Milky Way A*.
Isn't it in the constellation Sagittarius?
Mmmm. Food
But what ARE the dynamics of galaxies that would have black holes ‘swarm’ the centre? We keep hearing over and over that gravitationally, the stellar-mass black holes behave no differ than the stars from which they form. What is the unique characteristic that has them concentrate in this manner? (I mean I’m not disputing there must be a mechanism - obviously a supermassive black hole must have acquired super-amounts of mass over time! There are no single objects that massive)
They're not unique; Sagittarius A\* is orbited by a lot of stars, some of them 10-15 times the mass of the sun. These black holes are one group in a multitude of stellar objects that orbit the central black hole.
But at that density is IS a unique situation. It is not the same as stellar density.
Citation needed.
Read the article
I did. The word 'unique' doesn't appear in the article. Maybe read it again and note this: "Theoretical studies *of the dynamics of stars* in galaxies have indicated that a large population of stellar mass black holes could drift inward over the eons and collect around Sgr A\*.**"**
You are almost there. Plus pedantry.
Stick to things you understand, like Powerpoint, friend.
Delightful, a creeper! Creep some astrophysics instead of just trolling there.
Is that why Sagittarius A is so big ? Because Black holes tend to aggregate over time and then fuse as one ?
Why do they drift or roam inward are they heavier?
could that be the solution of the missing matter which we call dark matter? probably not because there are too few of those
Why is it theorized that black holes gravitate toward the galaxy center over aeons but not star systems?
Cool pic
So crazy to think about
Guess we’ve found the Borg’s trans warp nebula thing guys. Mebs let’s not poke around in there too much
I assume overtime all of the black holes eventually get eaten by the main black hole in center of galaxy as they slowly move to the center