Quasars and their black holes

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I was reading about quasars, and what I got from it was that quasars are extremely far away (3 billion + light years according to wikipedia), they were common in the early universe, and they have a supermassive black hole in the center of it.

My question is how did these quasars get such massive black holes? How could that happen so soon in the early stages of the universe? I don't know much about the formation of black holes other than they can form from the death of large stars.
 

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Perhaps you are carrying the meaning of the word "early" too far back to the very early universe. The early, universe, during which time necleosynthesis, occurred universe did produce sufficient material which led to black holes.

Here is an early unverse timeine provided by Wikki:


1 Very early universe


1.1 Planck epoch


1.2 Grand unification epoch


1.3 Electroweak epoch


1.3.1 Inflationary epoch


1.3.2 Reheating


1.3.3 Baryogenesis


2 Early universe


2.1 Supersymmetry breaking


2.2 Quark epoch


2.3 Hadron epoch


2.4 Lepton epoch


2.5 Photon epoch


2.5.1 Nucleosynthesis


2.5.2 Matter domination: 70,000 years


2.5.3 Recombination: ca 377,000 years


2.5.4 Dark ages


3 Structure formation


3.1 Reionization: 150 million to 1 billion years


3.2 Formation of stars


3.3 Formation of galaxies


3.4 Formation of groups, clusters and superclusters


3.5 Formation of our solar system: 8 billion years


3.6 Today: 13.7 billion years





Black Holes and Quasars
http://dnausers.d-n-a.net/dnetGOjg/Black/Holes.htm


>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>


Excerpt:

Ker Than

for National Geographic News


Published October 8, 2010


Monster galaxies with supermassive black hole hearts released fierce blasts that superheated the early universe, new Hubble observations suggest. The scorching conditions also stunted the growth of smaller dwarf galaxies, the new research shows.


Between 11.7 to 11.3 billion years ago, ultraviolet (UV) light emitted by quasars—enormous galaxies with supermassive black holes at their centers—stripped electrons of cosmic helium, according to observations made with the Cosmic Origins Spectrograph (COS) on NASA's Hubble Space Telescope. The big bang that created our universe occurred around 13.7 billion years ago.


http://news.nationalgeographic.com/news/2010/10/101008-black-holes-universe-galaxies-space-science/
 
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  • #3
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Your question is backwards.....black holes spawn quasars:

Quasars are believed to be powered by accretion of material into supermassive black holes in the nuclei of distant galaxies, making these luminous versions of the general class of objects known as active galaxies.
from the source below.....

Sounds like you may have read this already, but's it's a good overview:

The reason that so many are old is that available gas in the cosmos was most abundant then.....everything used to be a "gas", particles, before gravity had time to congeal it; as time progress, the gas is consumed and fewer quasars are formed within the visible universe; and those that quasars that were originally active begin to dim as cosmic gas is depleted in a region. " far away" also means "old".
 
  • #4
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Thanks for all the info guys. I haven't read everything yet but I'm getting there, it's really interesting stuff.
Another question until I find it in the reading...
What do quasars look like as they evolve? What do they look like today? It says they have the same properties as galaxies but much more powerful. Is it saying that quasars are the early stages of the universes early galaxies?
 
  • #5
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Thanks for all the info guys. I haven't read everything yet but I'm getting there, it's really interesting stuff.
Another question until I find it in the reading...
What do quasars look like as they evolve? What do they look like today? It says they have the same properties as galaxies but much more powerful. Is it saying that quasars are the early stages of the universes early galaxies?
My layman's understanding is that when a black hole has an abundance of matter to "feed on", as in it has a large accretion disk around it and lots of matter falling in, that matter gets moving super fast (near the speed of light) and gets super heated, thus shining very brightly. That is what is called a quasar. This accretion disk will in fact out shine its entire host galaxy.

In addition, if there is enough matter spiralling into the black hole, friction will cause it to shoot out gamma ray jets perpendicular to its plane of spin (hence perpendicular to the plane of the galaxy) that move at near the speed of light and extend out for light years. I'm not clear whether or not the presence of the jets are necessary to call it a quasar, though. Maybe someone can clear that up?
 
  • #6
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Your question is backwards.....black holes spawn quasars
As far as the details of how massive black holes form in the early universe....... We'll probably know better in a few years.

In addition, if there is enough matter spiralling into the black hole, friction will cause it to shoot out gamma ray jets perpendicular to its plane of spin (hence perpendicular to the plane of the galaxy) that move at near the speed of light and extend out for light years.
This is something else that we don't completely understand. It has something to do with magnetic fields. Magic happens. Jets form.

I'm not clear whether or not the presence of the jets are necessary to call it a quasar, though. Maybe someone can clear that up?
Pretty much since if you don't have a jet, you can't see anything so there isn't much of a quasar. One curious thing is that the object looks very different depending on if the jet is pointed to you or not.
 
  • #7
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What do quasars look like as they evolve? What do they look like today? It says they have the same properties as galaxies but much more powerful. Is it saying that quasars are the early stages of the universes early galaxies?
Current idea is that once the black hole finished eating up the gas, it starts looking like a normal galaxy.
 
  • #8
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In the early universe when there was lots of hydrogen, huge stars formed that had several hundred times the mass of the Sun. These stars eventually collapsed into black holes. Matter in an accretion disk spins in to the event horizon of a black hole. As it moves ever faster, electrons are stripped off and the atoms become charged ions. More material moves toward the event horizon than can pass through it and the “run off” ions form two opposing jets like a dynamo.
 
  • #9
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Quasars are suspected to be an evolutionary path to active galactic nuclei [AGN's].
 
  • #10
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In the early universe when there was lots of hydrogen, huge stars formed that had several hundred times the mass of the Sun. These stars eventually collapsed into black holes. Matter in an accretion disk spins in to the event horizon of a black hole. As it moves ever faster, electrons are stripped off and the atoms become charged ions. More material moves toward the event horizon than can pass through it and the “run off” ions form two opposing jets like a dynamo.
That's the best guess..... Might even turn out to be right. However.....

1) population III stars are still really hypothetical. Also not clear if the stars formed first or the black hole did.

2) throw stuff down a black hole (wave hands furiously) get a jet. We still really don't have a good model for how jets form from black holes.
 

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