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Questions tagged [supermassive-black-hole]

Questions regarding the most massive examples of black holes that typically reside at the centers of galaxies.

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Black hole density

How does more compression relate to a stronger gravitational pull. Like, when we say that a black hole is a tiny space that has 20-30 suns compressed in it, how does this increase its density and ...
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Black hole rotation and it's significance

Is there is any significance of the direction of black hole rotation with the nature of the instantaneous distortion of space-time curve, the jets coming up in the axis of black holes, and nature of ...
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What is the actual resolution of Event Horizon Telescope?

I am quite impressed with the recently published image of M87* black hole. It appears that this image achieves spatial resolution well above and beyond what was available until today. But how high ...
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M87. What was the black hole before?

10 seconds before the M87 black hole was a black hole, what was it? A star 10 times the size of our solar system?
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Can a star fall in a super massive black hole without getting destroyed?

This is the first of many similar questions I have to build up to a specific question or scenario that I want to explore and find an answer to.
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Event Horizon Telescope Data Cleanup

I was wondering how the researchers were able to minimize or neutralize confirmation bias regarding the data collected? As I understand it, the algorithm pruned much of the data, which would make ...
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Does the “photo of a black hole” taken by EHT actually depict a visible light-based scenario?

I'm still at my bachelor of electronic and communications engineering, so I'm not an expert of radiotelescopes; however, I surely know that, typically, radio communications are characterized by a RX ...
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Why not take a picture of a closer black hole?

There are closer galaxies than Messier 87 for sure, even ours! It sparked my curiosity that they went with one 53 million light years away. Is there a reason for this?
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What is the orientation of the M87 black hole image relative to the jet?

On the image of the M87 black hole released today by the Event Horizon Telescope team, which direction points towards the jet? Is it on the brighter side of the ring? To resolve ambiguity, I'm ...
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Why didn't the Event Horizon Telescope team mention Sagittarius A*?

At the press conference this morning, the Event Horizon Telescope team didn't say much about Sagittarius A*, which was the target many of us have been waiting for. Is there any explanation anywhere ...
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Are gravitational waves part of dark energy?

Do the current models of the universe consider the energy release of gravitational waves? E.g. iirc, the last black hole merger detected had a gravitational wave energy equal to ~3 solar masses (hope ...
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Quantum tunneling in black holes

My hypothesis is: "quantum tunneling in black hole". The matter which is consumed by a black holes is shifting to another part of the universe by quantum tunneling. Can it be possible?
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What happens if a black hole is produced inside another black hole?

Similar question here. The question I linked got me thinking. It is known that a black hole doesn't let anything escape its event horizon, not even light. Thus, naturally, anything that passes the ...
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What would happen if a star went supernova inside a supermassive black hole? [closed]

A black hole swallows a star. The star remains intact. Then goes supernova. What would happen to the star? Could we detect this event?
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How did they make a video of the center of the galaxy, and what is it exaclty that's flashing there?

The ESA video ESOcast 173: First Successful Test of Einstein’s General Relativity Near Supermassive Black Hole includes a clip of images of stars at the center of our galaxy orbiting around SgrA*, a ...
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Black hole, escape velocity, going up?

I do know nothing can escape a black hole, and I understand popsci explanation of geodesics of space-time around and inside the event horizon. I however have some trouble with following thought ...
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How to convert factors of time dilation into something relatable? [duplicate]

On this post, Time according to the gravity of Sagittarius A? They found the factor of time on the varying distances from the SMBH, I am curious on how to turn those factors into relatable terms ...
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What is it exactly about these flares of infrared light from Sgr A* that “confirms” it is a supermassive black hole?

CNET.com's SCI-TECH Scientists confirm a 'supermassive black hole' at the heart of our galaxy It's "mind-boggling", they say. This links to Astronomy.com's Scientists finally confirm the Milky Way ...
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What defines the plane of an accretion disk around a black hole?

The question Do we know at which angle the Event Horizon Telescope will look at the accretion disk of Sagittarius A*? about just how close to edge-on we would be viewing any accretion disk around the ...
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Do we know at which angle the Event Horizon Telescope will look at the accretion disk of Sagittarius A*?

Do we know at which angle the Event Horizon Telescope will look at the accretion disk of Sagittarius A*? Additionally, would it matter if we are exactly in the plane with the accretion disk, i.e. ...
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Can a black hole be torn apart by SMBHs?

Suppose two SMBHs (supermassive black holes) are brought close (e.g. during a galactic merger). Suppose that a "normal" black hole drifts into the space between the SMBHs. Could the gravitational pull ...
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Why smaller black holes are considered to be more dangerous than bigger black holes?

More massive the body is more is the gravity.Still often smaller black holes are considered to be very dangerous than the bigger ones,why?
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What will happen to the shape of a galaxy when a super massive black hole lying in its center dies(evaporates out)?

What's at the Center of the Milky Way? In this article it is said that a supermassive black hole lies in the center of milky way galaxy. At its center, surrounded by 200-400 billion stars and ...
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Why black holes are extremely cold?

"The most massive black holes in the Universe, the supermassive black holes with millions of times the math [sic] of the Sun will have a temperature of 1.4 x $10^{-14}$ Kelvin. That's low. Almost ...
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If a black hole has a mass of a universe what will be the volume of it?

Will it suck the entire universe in? What will the black hole look like to us, assuming we do not immediately get sucked in?
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Why is frequency different for gravitational waves coming from SMBHs vs small compact binaries?

Why do gravitational waves emitted by supermassive black holes binaries have low-frequency range (~10$^{-9}$ - 10$^{-2}$ Hz) than those emitted by stellar mass compact binaries (~10$^{-4}$ - 10$^2$ ...
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Singularity at the time of origins

According to the big Bang Theory, the universe have started from a point and it describes how the universe expanded from a very high-density and high-temperature state.The initial singularity was a ...
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Gravitational eddies across the galaxy?

I read about natural gravitational eddies that travel in a wave that black holes have. They also have a strong magnetic field. Does those eddies follow magnetic field lines of the rotating black hole? ...
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Is it possible that quasars are not powered by black holes but some other kind of compact, massive object?

AFAIK, objects in the universe thought to be black holes show evidence of radiatively inefficient accretion flow. But is this the case with Quasars? If not, is there a possibility that the core of a ...
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Black holes and super massive black holes [duplicate]

What is the difference between a black hole and a super massive black hole?
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Why is Sagittarius A* called so?

At the center of the Milky Way, we have a supermassive black hole. It's name is "Sagittarius A*". I was wondering that why is it called so? I mean, why "A*" why not just "A". Is there a naming system ...
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Black holes at the center of galaxies

At the center of massive galaxies there is a huge and massive black hole that radiates gamma rays. So at the center of the Milky Way there is also a huge and massive black hole and it also radiates ...
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How does dark SMBH evaporate?

I read that Dragonfly44 is a galaxy mostly consists of dark matter, and it should contain a super massive black hole too. If there really is a dark SMBH, how does it lose mass? I think there is no way ...
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Primordial supermassive black holes. How old are they?

I know that astronomers have detected supermassive black holes in the early universe. What was the age of the universe at which these black holes were detected? In other words how long is it thought ...
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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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Star systems forming when large gravitational force is applied

As far as I'm concerned, most star systems in our galaxy are traveling in fairly circular paths around the black hole at the center. Hypothetically, if a large gravitational force pulled star ...
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Spiralling in Galaxy evolution

Could some stars be orbiting galaxies in outward spirals instead of perfectly round circulation? Patterns of matter movement relate strongly to the galaxy centre. A special relationship between the ...
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Will biological process be disrupted under strong gravitational time dilation?

This question is raised by someone I've discussed with, after watching the movie "Interstellar", in which a clip showing Cooper and Amelia landing on Miller's planet near a super-massive blackhole and ...
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Why can't we see the supermassive black holes supposedly at the center of galaxies?

Is gravitational lensing responsible for obscuring (figuratively) the supposed supermassive black holes at the center of our own and other galaxies? By "see" I mean relative to the measuring tools we ...
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Could the big bang have created super massive black holes?

I understand that space was compressed to a single point and that during the big bang all points within that expanded away from each other at phenomenal speeds. I also have heard that during this the ...
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Looking for Galactic Data

I am doing some personal research and just and am trying to find a decent source for galactic data. Specifically I am looking for a database that includes the estimated size of the galaxy's ...
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Why do Seyfert Galaxies emit less energy than Quasars and Blazars, and how is the emitted energy measured?

When I was reading information about QSOs on a website, it said that Seyfert Galaxies emit less energy than Quasars and QSOs. Why do Seyfert Galaxies emit less energy than quasars, and how is this ...
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Galactic Filaments and their connection to Galaxy centre

If alliptical galaxies seem to a line with their associated galactic filament and that orientation is related to connections between the mass of said galaxy and the dominating central object, which ...
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Could a super massive black hole actually be primordial black hole in disguise?

If primordial black hole do exists today could it be responsible for galaxies maybe even quasars, I mean these ancient monsters gobble up all materials in its wake and grow bigger and eventually ...
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Are there upper or lower mass limits for black holes?

Natarajan & Treister (2008) describes a practical upper limit for black hole masses at $\sim 10^{10} M_\odot$. This is all due to the black hole's interactions with nearby matter. However, is ...
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What is the speed of gravitational waves ? [duplicate]

I read that two huge black holes collided or merged and so it created gravitational waves billion years ago , So now we are able to detect it & detected it. So what is the speed of gravitational ...
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Succinct explanation of black hole mass, diameter, shape?

I don't have any formal education in physics and I have found it hard to find a succinct and somewhat simple to comprehend explanation of what we think is the actual reality of a black hole. I'm ...
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Understanding “dex”

Hi I am trying to understand the concept of dex and how to use it in calculations. The usual definition is that it is the order of magnitude, so $10^{0.1}$ is $0.1$ dex. I want to do a simple ...
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Accretion discs emitting jets [duplicate]

When there are accretion discs jets of particles or radiations will be emitted in the direction parallel to the rotational axis. My beginner level astronomy textbook just says that it is due to ...
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Galaxy centre X structure - could this reflect impact of black hole at galactic centre

As reported in this science article X Marks the spot Centre of Milky Way, a X shaped feature is confirmed centered on our galaxy's centre, when looking on from within the plane of the Milky Way. In ...