Questions tagged [quasars]
Questions about quasi-stellar radio sources, active galactic nuclei that are far away and quite old.
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light emission of quasars
I'm studying Astrophysics and I have some video's from a past course. I'm currently studying the reionization of the universe. At the current point in the class, the instructor is talking about ...
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How are neutrinos produced in blazar jets?
I was watching the press release about measuring neutrinos and gamma rays from a distant blazar. One of the presenters mentioned that the neutrinos are associated with very high energy protons caught ...
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Why the space is so dark even there are billions of stars and many quasars emitting light [duplicate]
In our galaxy itself, there are millions of stars, and there are many more other galaxies in our local group and billions in the observable universes.
For sure they all emit a lot of light, still why ...
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Do gravitationally bound (e.g. orbiting) objects really resist the expansion of space?
Thinking about the expansion of space, it is commonly explained that gravitationally bound objects (like galaxies and galaxy clusters) will not be affected by the expansion of space (dark energy). I ...
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Regions and size of an AGN
In this diagram of the regions and approximate scale of an AGN:
which is from this paper, what do the x and y scales log(z/pc) and ...
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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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What compounds are present in 3C273?
Anyone know if we have any chemical reactions occuring in this quasar?
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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 ...
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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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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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