Questions tagged [quasars]
Questions about quasi-stellar radio sources, active galactic nuclei that are far away and quite old.
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Quasar Redshifts
How can the gravitational redshift of a very distant quasar be distinguished from its cosmological redshift? Quasars are very massive objects,thought to be supermassive black holes,so therefore must ...
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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 ...
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Anisotropy of quasar distribution
In a paper titled
Arp, H. (1984). Distribution of quasars on the sky. Journal of Astrophysics and Astronomy,
5(1):31-41.
at Journal of Astrophysics and Astronomy, Halton Arp wrote that there is ...
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Are quasars simply AGNs that are viewed from a particular angle?
I found the picture below in an answer to the post "Was the Milky Way ever a quasar". The picture is published on a website belonging to "NASA/IPAC Extragalactic Database". In the answer that has 16 "...
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What values can a color index variable get?
I am a statistician with love and passion for astronomy. I try to explain some outliers I found in the values of quasars - color indexes. I found four (4) values close to twenty (20). Is that ...
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Correction to inverse square law for cosmology
While reading about the discovery of quasars and the spectroscopic analysis of 3C 273 in this paper by Maarten Schmidt, I came across the following quote:
At these distances, corrections to ...
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How can gravitational lensing makes a quasar appear brighter?
How can gravitational lensing makes a quasar brighter than it would in the absence of a foreground galaxy?
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How does science knows what is the early universe?
I've read about Hubble seeing the brightest quasar in the early universe. Question is, how does science knows what is early and what is late?
Please correct me if I'm wondering, but after the big ...
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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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3C273 jet mass estimate
In this picture of 3C273, we can see a jet—estimated to be around 200,000 light-years long—being emitted.
I'm trying to find an estimate for the mass of the jet. It's a stream of ...
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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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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 ...
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