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

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16
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4answers
1k views

Does matter accumulate just outside the event horizon of a black hole?

My understanding is that time slows and approaches stopping when approaching the event horizon of a black hole. I have seen this explained several places, including a brief explanation in the last ...
4
votes
1answer
271 views

Collision of 2 black holes

There is a large number of visible Supernovas. Each week - about a 20 Supernovas Type 1a around the Universe. Is there collisions of Black Holes? What is this collision called? E.g. 2 black holes ...
30
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6answers
1k views

How are black holes found?

Black holes have so much gravity that even light can't escape from them. If we can't see them, and the suck up all electromagnetic radiation, then how can we find them?
8
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4answers
881 views

Escaping a black hole

I often hear that nothing can escape a black hole because it's "escape velocity" is greater than c. If that is accurate, what about the following. I know that the following has a lot of most likely ...
6
votes
2answers
424 views

Is it possible that a ultra-large portion of the space we live in is already inside a black hole? How could we refute this?

Trying to wrap my head around some concepts involving the very large gravitational fields of black holes, and what the gravitational gradients look like on a cosmic scale. I'm familiar with the Great ...
5
votes
1answer
75 views

How does an accreting black hole acquire magnetic fields?

There is actually a similar question on this site: Can magnetism escape a black hole?, however the answers do not focus on accretion, which is my main concern, so I start a new one. In Kip Thorne's ...
0
votes
3answers
318 views

What will happen if a black hole appears near our solar system?

We know that black hole possesses immense power and can destroy anything coming in front of it's path. If such a black hole appears near our solar system, are we going to survive? Is there any way not ...
19
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3answers
1k views

Why can't light escape from a black hole?

I've heard that light can't escape from a black hole. Can it? If not, why?
7
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2answers
1k views

How deep and shaped is the depth of a black hole?

A common representation of a black hole is a black circle which if I'm correct, indicates its breadth. This representation depicts it as a 'plate', so a really small depth compared to its breadth. ...
4
votes
4answers
782 views

Why did the big bang not just produce a big black hole?

Questions I've often wondered about: 1) If all the matter and energy were concentrated at a single point at the big bang, why wasn't that a black hole, or why didn't it form one? 2) If the reason #1 ...
10
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5answers
285 views

Orbiting around a black hole

Is it possible (for either a satellite or a planet) to orbit around a black hole? Do they attract everything around themselves into the center? Or they just affect gravitational force just like stars?
5
votes
2answers
144 views

Assuming a sufficient amount of mass above the density threshold, does the actual concentration of the mass matter in creating a black hole?

I've heard that the actual density of a black hole (within the volume of the event horizon) is pretty low - does that mean that any sufficiently large volume of mass over that density is also a black ...
3
votes
2answers
186 views

Relation between black hole mass and radius, and our universe's

Is there a graph of known black holes, with their estimated mass in the X axis and their estimated radius in the Y axis? If so, where can we find it? I would like to know if a black whole with the ...
1
vote
0answers
29 views

Are there collected data about the direction of rotation of black holes and the direction of the magnetic field?

Is there a relation between the direction of rotation of black holes or neutron stars and the magnetic dipole moment of BH or neutron stars? BTW, are there different directions of this two parameters ...
25
votes
2answers
6k views

Can our Sun become a black hole

Does every star become a black hole? Is there any probability that our sun can become a black hole? If yes then is it on its way to become a black hole? what is the current state of sun as per the ...
20
votes
5answers
1k views

Can we (theoretically) spin the black hole so strong that it will be broken apart by centrifugal force?

I can't imagine the forces involved in black holes' lives. So please, help me to find out, if it is possible or not to destroy black hole in this specific way.
18
votes
2answers
7k views

How does neutron star collapse into black hole?

We know the spectacular explosions of supernovae, that when heavy enough, form black holes. The explosive emission of both electromagnetic radiation and massive amounts of matter is clearly observable ...
6
votes
3answers
519 views

What is a singularity? What is at the center of a black hole? Specifically regarding space-time

So because I can only really think of space-time in 2-dimensions like a sheet of something, my assumptions might be wrong to begin with. I was watching a YouTube video on black-holes and there was a ...
5
votes
4answers
626 views

Do Roche limits apply to black holes?

Consider black hole A, a super massive black hole at the center of the galaxy. Orbiting it is black hold B, a less massive black hole. If some passing body were to modify black hole B's orbit such ...
4
votes
2answers
326 views

Camera reaching the event horizon

This question came to my mind after reading this. I think it is safe to assume that the supposedly thrown camera would not reach the event horizon in one piece. So my question is : If I dropped a ...
6
votes
2answers
169 views

Ninth planet - what else could it be?

So recently it was announced that there might be a ninth planet out there. Some people (from NASA) say the odds are 50% that it is a real planet, since it hasn't been discovered by telescopes yet. ...
6
votes
4answers
867 views

Can magnetism escape a black hole?

I know light, and practically nothing but gravity can escape a black hole. My question is: can magnetism escape a black hole? A couple things that convince me it can are: Jupiter's magnetic ...
5
votes
3answers
600 views

Do black holes have energy?

So black holes are created by certain dying stars and when the star runs out of nuclear energy gravity wins out and the star implodes. An entire star’s mass collapses down into a smaller and smaller ...
4
votes
2answers
2k views

Does a black hole become a normal star again?

Stars which satisfy the Chandrasekhar limit can become a black hole. What happens to star after it becomes a black hole? Does it regain its status of star?
4
votes
2answers
333 views

Why does time get slow near a black hole? [closed]

Why exactly does time get slow around a black hole? And does it provide a way to go into the future?
3
votes
1answer
127 views

What does black hole evaporation correspond to in the accelerating universe / black hole analogy?

In the same way, as a black hole emits Hawking radiation corresponding to its temperature $$ T = \frac{\hbar}{r_{BH}} $$ the accelerating universe can be described as all of the stuff falling ...
3
votes
2answers
6k views

Life planets orbiting black-holes. Can/Do they really exist?

So, I watched Interstellar and if you watched it too you know that there's a planet orbiting a black-hole, they call it Miller's Planet. According to the movie, every hour on Miller's Planet is ...
3
votes
2answers
128 views

What happens when two black holes collide? [duplicate]

There are many hypothesis saying that there will a collision between the milky way and Andromeda galaxy...so what happens when two black holes will collide?? And how will it effect the other objects ...
1
vote
1answer
62 views

Under Earth's gravitational pull, how dense would an object have to be to reach its Schwarzschild Radius?

The Schwarzschild Radius is a theoretical radius, that if the mass of the object was compressed into that certain radius, the escape speed from the surface of the compressed object would equal the ...
1
vote
1answer
172 views

Is a black hole a 5 dimensional vortex?

We know that a black hole behaves like a whirlpool or a tornado or any of the other rotating phenomena we experience on Earth.But the thing is, all these phenomena, except the black hole, are 2-...
1
vote
2answers
147 views

A camera and time dilation?

If I travelled near a black hole, my time would progress slower relative to someone on Earth. This is clear enough. However, what if we sent a probe with a camera to a black hole? When we watch the ...
1
vote
1answer
141 views

Do black hole singularities actually merge?

new questioner here so please be gentle. Do the singularities of merging black holes actually merge together? I mean there are 2 infinitely small objects (singularities) that are trying to find each ...
0
votes
1answer
180 views

Black Holes, how do they form?

Do black holes form by when the massive star dies and all the gravity falls in on itself, or something else. Please let me know, I'm really desperate!!