Questions tagged [quasars]
Questions about quasi-stellar radio sources, active galactic nuclei that are far away and quite old.
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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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Can I take logarithms of magnitudes (which are already log) [closed]
I'm investigating the relationship between the magnitude of quasars in various wavelengths, and their redshift $z$. I've found that if I take the $log$-$mod$-transform ($L_{mag}$) of the magnitudes, ...
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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 ...
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Quasar mass and accretion rates
This page on Wikipedia -- Quasars mentions that the "The largest known [quasar] is estimated to consume matter equivalent to 600 Earths per minute". However, there is no citation for this comment. How ...
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Can we extract power from quasars? [closed]
As they say, "In cosmos near earth but beyond atmosphere there are too much dangerous and powerful radiation frm quasars or gammy burst .,etc". So if there is so much cosmic radiations being emitted, ...
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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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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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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 ...
CommunityBot
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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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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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How to find the distance between two quasars
I want to calculate the distance between two quasars of which I know the angular position and the red shift. Let $Q_1=(\alpha_1,\delta_1, z_1)$ and $Q_2=(\alpha 2,\delta 2, z_2)$ and suppose $z_2 > ...
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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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