Questions tagged [quasars]
Questions about quasi-stellar radio sources, active galactic nuclei that are far away and quite old.
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Gravitational lensing of quasars
Are there any cases in which the gravitational lensing of a quasar has been observed in both visible light and in radio waves, and if so, is the radio-wave resolution good enough to show that the ...
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Has the Lyman-alpha forest ever been used to test Arp's theory?
Has the Lyman-alpha forest ever been used to test Halton Arp's theory that quasars are not cosmological but instead are ejected from relatively near-by galaxies? If Arp was right, then the spectra of ...
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What resolution is needed to see a quasar through the galactic center?
The center of the galaxy is densely packed with stars and obscured by a whole lot of dust between us and it. For those reasons, groups that study the motion of stars around the super-massive black-...
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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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What is high redshift?
I'm curious about the difference between low redshift and high redshift universe. Is there any defined limit of redshift beyond which we call things high redshifted?
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Redshift quantization
A full disclosure to begin with: I'm a PhD student in mathematics and while I understand most of standard cosmological-astronomical terms and I've followed a one semester course on cosmology, I don't ...
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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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Extraction of error spectrum in Sloan Digital Sky Survey
I need to know does SDSS spectrum contains error spectrum as well?
http://www.sdss.org/dr12/spectro/spectro_basics/#AbouttheSpectra
The above link says, further HDU's contain error spectrum and than ...
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What would be the outcome for life in our galaxy if the merger of the Milky Way and Andromeda creates a Quasar?
If predictions are correct, the Milky Way and Andromeda are set to collide in around 4 billion years. If, when this occurs, a Quasar is formed by matter being accreted to the common galactic center (...
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Quasars and Gamma Ray Bursts
Has there been any study to suggest that either quasars of gamma ray bursts are more detectable from further distances in the universe?
I've read that quasars are the most powerful energy in the ...
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What is the scale of things you can see with gravitational lensing?
I'm trying to understand the examples of gravity lensing (using the general relativity property of large masses to bend light like a lens).
Most of the examples I see are of some galaxy (presumably ...
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Has the most luminous object in the universe been found?
It's hard to search through the entire (observable) universe, but the most luminous thing there is must on the other hand be easy to find. Can we now say that the most luminous quasar we know, is the (...
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What is projected separation and how can I make sense of its unit (h^-1 kpc)?
I have been reading this paper on the separation of a binary quasar in which it states:
At a projected separation of 8.3/h kpc (Omega_matter = 1), CTQ 839 would be the smallest projected separation ...
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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 ...
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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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