Questions regarding gravitationally bound systems of hundreds to thousands of galaxies as well as interactions between such systems.
Questions tagged [galaxy-cluster]
100 questions
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To what extent do the spin of smaller celestial bodies reflect the spin of the larger system’s of which they are a part?
One can ask whether two objects are spinning in the same direction or not. For example, the Sun, Earth, Luna, most of our solar planets (except Venus and Uranus), and the planets’ satellites all spin in approximately the same direction. Likewise,…
John
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Why does the concentration-mass relation of galaxy clusters have a negative slope?
As reported in some recent observational works works (ref. Merten et al. 2015) the concentration-mass relation of galaxy clusters has a negative slope. This means that at a fixed redshift, haloes with a higher mass have a lower concentration.
Some…
Gananno Rigatoni
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Why does the Bullet Cluster have many names?
On Wikipedia, there are two names to call the Bullet Cluster, '1E 0657-56' and '1E 0657-558'.
Furthermore, even on the NASA Hubble Space Telescope site, they call it '1E 0657-556'.
Why is the bullet cluster's name not the only one?
BAO
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Are there small voids of 10 - 20 megaparsecs also within, and not only between superclusters?
I sincerely apologize if this question is stupid, however after all the articles I read so far, I could not confirm this assumption, which I think is actually a fact, but I'm not completely confident.
I'm writing on the topic of proportions of the…
InAwe
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How many galaxies are there in the Hercules–Corona Borealis Great Wall?
The Hercules–Corona Borealis Great Wall is "to date (February 16, 2015), it is the largest and the most massive structure known in the observable universe" (source). How many galaxies is the Hercules–Corona Borealis Great Wall believed to contain?
user5581
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Estimating the virial mass of a galaxy cluster from its $M_{500}$ measurement
In this paper, the authors seem to calculate the virial mass of the Fornax cluster by using its $M_{500}$ value. In the section 4.1, they say its mass was measured to be $M_{500}=6.4\times 10^{13} h^{-1}M_\odot$ and then adds that the corresponding…
Nownuri
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Interpretation of Angular Correlation results
Long story short, what I am doing is to split the spherical space around my device into equal size pixels (49,152 pixels) with HealPix algorithm. If the power that my device can receive at each pixel is equal or higher than a certain threshold, I…
Shabani
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Coma cluster of galaxies
According to wikipedia (https://en.wikipedia.org/wiki/Coma_Cluster), Coma cluster contains over 1000 galaxies. Is there any upto date catalogue of these galaxies with the following given parameters (Ra, Dec, z, magnitude, position angle, major…
An student
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