All Questions
Tagged with quasars black-hole
11
questions
10
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2
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2k
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What is the mechanism through which mass is converted to thermal energy in the accretion disc of a black hole?
In the book The Cosmic Perspective, it is stated that as matter is falling into a supermassive black hole, up to $40\%$ of its mass are converted to thermal energy, making the accretion of matter ...
- 203
2
votes
0
answers
87
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How does hawking radiation work without virtual particles?
How does hawking radiation work without the existence for virtual particles? I read that certain quantum fields are distorted when a black hole forms on top of them. But what fields specifically? If ...
- 41
2
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1
answer
144
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How do accretion disks around black holes evaporate via winds?
I'm curious as to how accretion disks around black holes evaporate. I've heard winds play a crucial role in this. But what winds specifically and how do they form? Is it a stellar wind of sorts? If so ...
- 41
7
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1
answer
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How bright would Sagittarius A* be from Earth if it became an Active Galactic Nucleus?
Essentially I'd like to know how bright our central black hole could appear from earth in relation to full moon brightness. Assuming maximum energy output (like when it's gobbling up an entire ...
- 71
1
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0
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Causes of emission of accretion disk
As far as I can see, there are two main sources for the emission of energy from an accretion disk:
release of gravitational potential energy of the infalling matter;
friction from differential ...
- 2,600
1
vote
1
answer
137
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How to convert the observed magnitude of a Quasar to it's bolometric luminosity?
How can I convert the observed magnitude to Bolometric Luminosity? I know the relation for the star but should it be same for a Quasar? Basically I want to convert the X-axis of this plot to ...
- 187
3
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0
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56
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What fractions of matter are retained and displaced by quasars?
Following on from a query concerning quasar mass, what fraction of matter is ejected compared to matter that is lost to the BH?
Is there a graph that describes the fractions of the mass of quasars ...
- 4,268
1
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2
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206
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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 ...
- 111
1
vote
1
answer
133
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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 ...
- 418
1
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1
answer
185
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Does 2 merging black holes necessarily make a quasar?
2 black holes are about to merge to become a larger black hole. Does this mean it'll become a quasar?
From what I know, quasars are supermassive black holes or a collective amount of them. So, if it ...
- 1,301
2
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If quasars are powered by black holes, why are they so bright?
If a black hole can swallow everything, even light, then how can a black hole power anything, particularly something as bright as a quasar. Why doesn't the black hole swallow the light of the quasar?
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