Questions tagged [galaxy-clusters]
This tag is for questions relating to the galaxy cluster or the cluster of galaxies, gravitationally bound grouping of galaxies, numbering from the hundreds to the tens of thousands. The important fact about it is that , collisions between galaxy clusters provide a unique opportunity to study matter in a parameter space which cannot be explored in our laboratories on Earth.
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Questions about cosmic sheets/walls/filaments
I had a couple of questions about cosmic filaments in the context of the cosmic web structure formation:
In this thesis (https://www.imprs-hd.mpg.de/51939/thesis\_cpenzo.pdf), the author indicates in ...
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Why isn't the "Dark Matter" in the Bullet Cluster supermassive black holes?
I've seen several videos that claim that the Bullet Cluster is evidence for Dark Matter. The general idea is that the gas is trapped on one side of the collision and the light-bending "Dark ...
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How does dark energy affect the dynamics of galaxy clusters?
Galaxies interact with each other gravitationally (just as every other celestial object) and in many cases they form groups or clusters.
Does the expansion of the universe (or dark energy) affect the ...
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Pressure and velocity dispersion
I’m reading this paper
whose Eq(2) I’m a little concerned about. Sanders has tried to relate the pressure with the velocity dispersion of particles using the relation $P=
\rho\sigma^2$ where $\sigma$ ...
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Is there dark matter in intergalactic space?
Reference: the rotation speed of galaxies in a galaxy cluster:
Is the dark matter associated with each galaxy in a cluster, sufficient to explain the rotation speed of galaxies in the cluster, or ...
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How did Zwicky discover dark matter?
According to Wikipedia Zwicky used "virial theorem" to discover the gravitational anomaly in the Coma Galaxy cluster. But I also remember reading that he used Kepler's third law. Which one ...
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Dwarf galaxy rotation speed around Andromeda/Mily way
We know that the rotation speed of stars around the center of a galaxy is roughly flat.
But how fast does the dwarf galaxy rotate around the bigger galaxy, say andromeda or milky way?
Do they also ...
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Database for galaxy luminosity (or mass) distribution
I'm trying to get data on luminosity (or mass) distribution for galaxies.
I came across one paper (https://arxiv.org/abs/1106.3564) which gives luminosity distribution for Andromeda.
But is there any ...
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Distance $r$ between galaxies inside the galaxy cluster
I am currently working on the dynamics of the galaxy cluster, so i am trying to get the distance $r$ between the galaxies inside the galaxy cluster from its centre. As a input i have RA , DEC and Z ...
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If spiral galaxies form due to perturbations, why aren't there more spiral galaxies in galaxy clusters, where interaction/perturbation is likely?
I read the other article with an excellent explanation of simulation results and the mathematics behind spiral arm formation yet was left baffled by the point that the principal influence that would ...
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How loud is the Perseus cluster?
The gas near the center of the Perseus cluster exhibits quasiperiodic pressure oscillations that can be interpreted as sound. I found a paper that says that these pressure waves have a wavelength of ...
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Why are most ring galaxies present in the field instead of rich galaxy clusters?
I was reading an article in which it said that mostly ring galaxies are present in the ‘field’ instead of rich galaxy clusters. Can anyone explain why is it so? I read about it's formation and i ...
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Does a star that is far from any galaxy tend to rotate slower?
I'm wondering whether the rotation of a galaxy and the buffeting of the gas and dust within it by light and stellar wind and pressure waves makes nebulae or gas clouds in galaxies have more angular ...
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Why is the Hubble law so accurate at scales smaller than galactic voids?
It's possible to derive the Hubble law:
$$v = H_0 d$$
from the FRW metric by differentiation.
Experimentally the Hubble law appears to hold for relatively small distances, say 20 Mpc and smaller. ...
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Are galaxies and clusters of galaxies much denser when we observe the 'past' far universe than the 'present' closer part of the universe?
Are galaxies and clusters of galaxies much denser when we observe the 'past' far universe?If the universe is expanding, the galaxies should have been much closer in the past so should we see a larger ...
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