Questions tagged [star-cluster]
Questions about large groups of stars bound together gravitationally. Use both for globular or open clusters.
53 questions
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Which Survey has recorded the radial motion of Pleiades (M45)?
I made a stellar model and I want to know how accurate that model is by comparing with a real stellar system. So, I looked it up in Gaia dr3, but the radial velocity of only 1 object is mentioned out ...
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Can we theoretically estimate the number of stars in an open cluster using the IMF?
Can we theoretically estimate the number of stars in an open cluster using the IMF? If it's possible, I’d like to know what physical quantities need to be measured observationally when estimating the ...
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What is meant by the 'King core radius'?
While looking for a parameter that represents the extent of a star cluster, I came across the King core radius ($r_c$). However, even after reading papers, I still don’t understand it. What does the ...
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Methods for determining the extent of an open cluster
I derived an H–R diagram for M45 using Gaia data by applying a parallax window and an angular radius around the cluster center. However, I chose the parallax window ad hoc around the literature ...
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Which two stars of the Pleiades appear as a single star?
Which two stars of the Pleiades are so close to one another from Earth's viewpoint that they appear as a single star?
The Pleiades is Taurus' cluster containing the "Seven Sisters". And yet:
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Why is estimating the age of an individual star so complicated?
I have several books on stellar evolution (where one comes from the American Astronomical Society's IOP Astronomy textbook: Understanding Stellar Evolution, by Henry J. G. L. M. Lamers and Emily M. ...
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Estimating the mass of a globular cluster
Here's the complete statement of the question:
Estimate the mass of a globular cluster with the radius $R = 20\ pc$ and
root mean square velocity of stars in the cluster is $3\ km/s$.
This problem ...
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Are there any star clusters associated with nebulae that have well defined 3D positioning of the stars in them?
I am doing a project where I am trying to recreate a star cluster in 3D space using some cool retro™ neon Nixie tube indicators.
My first choice was LBN 1015, a nice group of stars with a small ...
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Determine the age of an open cluster (M41)
I'm currently conducting a photometric study of the M41 open cluster and have successfully built its Hertzsprung-Russell diagram. Now, I'd like to estimate the age of the cluster by fitting an ...
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When should we use direct O(N^2) N-body simulation (instead of other methods)?
I've read a small tutorial on N-body simulation methods. What it says about direct N-body simulation is:
These codes are often used in star cluster dynamics or in other contexts where multiple stars ...
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What are morphologies in star clusters?
While studying astronomy, I came across the term morphologies of stellar clusters, and I don't understand how that works. For context, I came across the term "The embedded stellar clusters in NGC ...
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Who named "the 37 cluster" or at least made that name widely known via writing?
The March 29, 2024 Veritasium video Why is this number everywhere? is about an apparent prevalence of the number 37 (for at least some people, including ) and in a montage of instances of 37 it shows &...
user7982
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Is gravitational lensing "additive" in a line of sight?
As usually depicted, gravitational lensing implies, at least, three objects: a distant source, an observer, and a "massive enough" object in the middle, where enough is the mass needed to ...
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If a cluster of stars in dynamical equilibrium falls into a much larger blob of dark matter, will it get hotter and expand? Will it stop?
This question is inspired by ProfRob's inspiring answer to Are there really confined Globular Clusters? in which he invokes the concept of "virialization" where a dynamical system reaches ...
user7982
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Bica 5 open cluster
Someone referred to the open cluster Bica 5. Is that to do with E Bica? How would I get information about this cluster? I do not have many options. I have been just trying general searches using ...
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