Questions tagged [black-hole]

Questions regarding points of extremely high mass density, which creates an extremely strong gravitational field from which light cannot escape.

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1answer
109 views

Is it fruitful to search for a correlation between rates of in-falling matter in black holes and the expansion rate of our universe? [duplicate]

To my understanding, white holes are hypothetical objects that are time-reversed black holes; black holes gravitationally "suck in" matter whereas white holes "spit" matter back out. As such, I think ...
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What's that ring that only now appears in black hole illustrations?

If you'll notice, space time starts to deform near the black hole, but then at considerable distance from the black hole' surface, images in the background become ultra-distorted, but then as you look ...
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If one galaxy were to collide with another, what would it look like to an immortal inhabitant of one of their planets?

I was reading this article posted on /r/space about photographing black holes, and they showed a picture of what's believed to be two black holes formed from two galaxies colliding. I didn't realize ...
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Items at the Event Horizon vs. colliding Black Holes

Items reaching a Black Hole's Event Horizon seem to be frozen in time from the point of view of an outside observer. On the other hand, Black Holes collide and merge, in finite steps, producing ...
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Can we create neutron star by pressing earth? Or other objects?

Everywhere I can hear, that if we press anything to the right size, we create black hole. Can we create neutron star by pressing, for example, our planet? And what if we press something bigger, like ...
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Is there a maximum size for a black hole?

As far as I understand it black holes radiate Hawking radiation and probably gravity waves, which over time causes them to lose mass and eventually evaporate after almost unfathomable amounts of time. ...
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Behaviour of black holes

This question could be strictly linked to my another question related to black holes. It’s known that the horizon event is a place where dust,star components are ready to be incorporated to the ...
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Is it correct to assume that the relationship between an objects mass and size, is what decides if it’s a black hole or not?

I’m asking this question in reference to a scenario I saw posted a couple of days ago, where it’s stated that if you would shrink earth to the size of a cherry, it would become a black hole. Is it ...
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Why do Black Holes in the middle of galaxies not suck up the whole galaxy?

As stated in several sources, it's supposed that in every galaxy there is a black hole in the middle. My question is, why do these black holes in the middle of galaxies not suck up all the ...
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How can a singularity rotate?

So I've heard that all black holes that have been observed rotate to some degree. But if it has zero radius, how is it even possible for the black hole itself to be spinning? Or is it just all the ...
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The size of the radius of the event horizon of a black hole created by the merger of a black hole binary system

Let's assume that you had a black hole binary system and everything said here is possible. Their large masses would lead to a large emission of gravitational waves. The loss of orbital energy and ...
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What will the universe be like in a googolplex years time?

It will be cold and dark in 10^(10^100) years. What else can be said of the state of things in the far distant future? Will everything have fallen into supermassive black holes and then radiated ...
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1answer
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Does a kilonova leave a high mass remnant?

My understanding of Type Ia supernovae is that they are expected, in most cases, to destroy the white dwarf(s) that went in to them, leaving behind no high density remnants (i.e. no white dwarf, ...
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Could a pulsar in orbit around a black hole feed the black hole with its radiation?

Could the black hole consume the radiation? If so, could the pulsar radiation absorbed by the black hole make it grow steadily more massive over the course of billions or trillions of years?
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Singularity in Black holes? [duplicate]

What is a singularity (black holes)? What happens to time and space at that point? What does it leads to?
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Reshaping black holes to “push” the event horizon

I watched this simulation made by LIGO (Laser Interferometer Gravitational-Wave Observatory) where 2 black holes merge into one. https://www.youtube.com/watch?v=I_88S8DWbcU I was therefore thinking ...
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Can we peek into a black hole with magnetic waves? [closed]

Aside from the fact that nothing we know of, excluding pure energy can escape from black holes. They affect both space and time in a manner that nothing else can quite compare to, and usually have ...
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Binaries consisting of a black hole and a non-black hole?

Are there any known binary systems in which one member is a black hole and the other is not a black hole (main sequence star, giant, neutron star, white dwarf, whatever)? Googling seems to turn up ...
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The consequences and the mechanisms of a shift of the Earth away from the sun

First premise: I have already made this question in the worldbuilding section, but since it is a very specific question many have recommended me to write in the astronomy section so here we are. ...
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What would it feel like to be orbiting near a merging black hole?

The recent 4th discovery of gravitational waves where the black hole masses were 31 and 25 times the mass of the sun, and they released 3 solar masses of energy as gravitational waves, made me wonder ...
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Parent stars of our Sun - Where are its remains?

This is in a way related to this question. Question is: Our star is third generation star, which is explained by existing Barium. That Barium was created by other stars. Now, those stars must have ...
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The photos of the outer space

How did the humans take photos for the galaxies, black holes, stars, nebulas etc in the outer space?! I guess they went out of the Earth planet and nearly out of the Milky Way galaxy by space-ships ...
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How far is the nearest black hole from our solar system? Is there an official list?

Which is the nearest known or suspected black hole from our solar system and how far is it from us? Is there an easily-viewed catalog that astronomers use to keep track of these?
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whose gravitational pull is more stronger , Neutron Star or Black hole?

We know neutron star is very densest in the universe and it weighs the thousand times of our Sun. And Black hole having strong gravitational pull not even light can escape From it . So , whose ...
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Use of kugelblitz to delay heat death [closed]

I may be way off the mark here, but wouldn't it be possible to use kugelblitz (artificial black holes formed from a concentration of radiation rather than matter) to significantly delay heat death? ...
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How did the object CO-0.40-0.22 get its name, and how is it distinct from CO-0.40-0.22*?

There seems to be three things described in the recent Nature Astronomy paper Millimetre-wave emission from an intermediate-mass black hole candidate in the Milky Way: Molecular cloud CO–0.40–0.22 ...
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what is the dimension of Black Hole? [closed]

Black hole is the densest .... in universe. We know that dimension of universe is 4D . So, what is the dimensions of black hole? Is string theory explains what is it's dimension?
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Do anti-particle black hole exist and can they evaporate? [duplicate]

I know that virtual particles are constantly be created and annihilated even in a complete vacuum, I like to know if there exist such a mechanism to spawn an anti-particle black hole can be any size ...
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Is it possible to throw a camera attached to a rope within the event-horizon of a black hole and then pull it back in?

I have heard that when something passes the event-horizon of a black hole nothing can stop it from getting pulled in. Is that true for objects partially past the event-horizon? Would it be possible to ...
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How many wandering black holes are there in the milky way?

I have attempted to research this topic due to curiosity, but I have yet to find a credible answer, the best I could find is this article, which has no listed sources, and the author has also done ...
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Stars orbiting supermassive black holes

I read an article on a group of stars orbiting the supermassive black hole Sagittarius A. Did these stars get caught by the black hole's gravity like planets capture moons, or were they born from the ...
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Could a closely orbiting pulsar be used to study a black hole?

If we were to locate a pulsar in a close elliptical orbit around a black hole, could this reveal significant information about the black hole (e.g. time dilation / structure)? Could this even tell us ...
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Is there an official list of objects in the sky?

I would like to know how many known quasars there are in the Universe as well as x-ray binary black holes (not Neutron stars) but I don't seem to be able to. I also want to know how many black holes ...
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How do black holes lose their mass? [duplicate]

As I was searching the answer to 'What comes after Black Holes', I found these two threads talking about the same thing Do black holes die? Can a black hole reach a limit where it can no longer ...
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Why do medium stars collapse to form supernovae while big stars collapse to form black holes?

I understand that a star runs out of fuel slowly and gradually by fusing heavier and heavier particles (because of pressure by gravity) until the last heaviest particle is not able to fuse at the core ...
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1answer
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Could we see planets around active Stellar Mass Blak Hole?

This question is a followup of Is there any theoretical or empirical research about planetary systems with a black hole in their center?; Since it is possible to detect planets around stars with the ...
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Is there any theoretical or empirical research about planetary systems with a black hole in their center?

I assume such a system would be hard to detect due to a lack of radiation, at least if the vicinity of the black hole does not contain a lot of mass which falls into it over time, thus creating (a lot ...
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How do we know that Singularity is not an object with reasonable radius?

So for example: a Neutron star has a radius of 10km and 2 solar masses. A singularity can have a radius of 1m and 10 solar masses, with a 1km event horizon radius. Basically it will just be a more ...
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What does it mean 'black holes is created when center of a very massive star collapses in upon itself'?

I read many times that black holes is created when center of a very massive star collapses in upon itself but what does it mean ? Does weight of center of massive star increase so much that itself can'...
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Can electromagnetic waves be affected by gravity?

Can electromagnetic waves change their properties in the presence of gravity?
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Was Milky Way formed after Sagittarius A Explosion?

Is it possible that most galaxies (and our galaxy) were formed from leftovers of supernova explosions? In order to have a black hole 4,000,000 x solar mass the initial mass of the star should have ...
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What is this bright “glow” in the center of galaxies?

It was always my belief that at the center of many galaxies, there are supermassive black holes. If this is the case, then we should not see a "light" coming out from the center since light get's ...
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How strong would gravity need to be to prevent star formation

This question got me thinking. In another universe, with a different value for the gravitational constant G, how much bigger would G need to be for star formation to be prevented? In other words in ...
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Why does gas form a star instead of a black hole?

When a space gas gets pulled together a star is formed. On the other hand, when a massive star dies, it collapses to a black hole. You would think that the initial mass of the gas would be bigger ...
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Universe and black holes

I know that the radius of the observable universe is about 46.6 billion light years and is expanding at every instant of time due to dark energy . So is it possible that we our entire universe could ...
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From where does the energy for gravitational waves come from?

As far as I understand, in the events detected by LIGO, about 4% of the total mass of merging binary black holes was converted to gravitational waves. Where does this energy come from, i.e. what ...
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Are there any physical phenomena that destroy information?

Are there physical phenomena, such as wave function collapse or black holes, which irrevocably destroy information about their prior states?
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Does the Canis Major Dwarf Galaxy have a black hole at its centre?

I am just wondering: is there a potential galactic centre out there that's very close to us? I know that CMDG is irregular, but can it still contain a black hole at the centre?
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Does a White hole lies behind a Black hole?

While reading about a White holes, I stumbled upon a question "Where does the matter emitted by a White hole come from?" There seems to be 2 possible candidates: It was the matter engulfed by a ...
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1answer
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Theoretical measure of distance to black hole?

Would it be possible to measure the distance to a black hole of known mass by measuring the radius of the most redshifted radiation that is detectable? The idea is that since the point where that ...