Questions tagged [quasars]
Questions about quasi-stellar radio sources, active galactic nuclei that are far away and quite old.
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Why would the merger of spinning black holes within the accretion disk of a supermassive black hole cause them to "shoot straight up" out of the disk?
I just tried to read the new New York Times article Two Black Holes Colliding Not Enough? Make It Three which links to the new 25-June-2020 Physical Review Letter Graham et al. Candidate ...
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What enhances the capture and merge rates of pairs of small black holes orbiting around supermassive black holes?
I just tried to read the new New York Times article Two Black Holes Colliding Not Enough? Make It Three which links to the new 25-June-2020 Physical Review Letter Graham et al. Candidate ...
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In the 1950's how were radio-astrometric positions with portable dishes so precise they could be assigned to their dim optical counterparts (Quasars)?
In my question Why are quasars so far away that they couldn't be optically resolved in the 1950's? I included the following short paragraph, but then added strikethrough to the second sentence ...
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Why are all quasars so far away?
Why are all quasars so far away?
If the universe is homogeneous, we should expect to have a homogeneous distribution of quasars, but all of then seem to be far away from Earth. Why is that?
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Difference between quasar and Active Galactic Nuclei?
Are there any differences between quasars and Active Galactic Nuclei (AGN)? As I understand it, they are both caused by extremely luminous electromagnetic emission from material accreting onto a ...
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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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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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How often does the supermassive black hole in the Milky Way become a quasar?
My current interest is black holes and quasars. I was wondering how often they erupt--specifically ours? Would it be blindingly bright on Earth? Finally, would there be any effects that would alter ...
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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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How to interpret this spectrum of the "new DESI Quasar at z = 6.53"; what causes the big edge at about 9150 Angstroms?
I'm not exacty sure why but Scitech Daily's Seeing Dark Energy’s True Colors: DESI Creates Largest 3D Map of the Cosmos includes the graphic and caption below.
It indicates a quasar in a Hubble image ...
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Intergalactic Lyman-alpha absorption for high redshift quasars (Gunn-Peterson effect)
This is a follow up to a recent question on SE asking about the apparent suppression of radiation shortward of the (red-shifted) Ly-$\alpha$ line of a quasar at redshift $z=6.53$.
The general ...
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Can the Hubble expansion inject energy in AGN and quasar outflows?
I found this article about the behavior of quasar outflows in cosmology and how they can create a magnetic field.
In section 2.1.4., the authors say that when a quasar produces a "wave" or ...
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Obtaining the Light curve of a a Quasar
So, I am relatively comfortable with handling $\textit{FITS}$ files and hence I choose Python for the following operation.
The thing is that I need to analyse some Quasar light curves and hence I went ...
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Why are quasars so far away that they couldn't be optically resolved in the 1950's? [duplicate]
Wikipedia's Quasar includes the following in its introduction:
The term quasar originated as a contraction of quasi-stellar (star-like) radio source, because quasars were first identified during the ...
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Obtaining the Flux-Time plot for a Quasar
As a follow up question to Obtaining the Light curve of a a Quasar, I wish to know how to obtain a Light curve for a quasar observation like this data set over here.
Is there an archival repository ...
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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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