What Is Integrated Visual Magnitude in Astronomy?

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Integrated visual magnitude in astronomy refers to the overall brightness of a star cluster, taking into account the magnitudes of individual stars. In the discussed globular cluster with 10,000 stars, 100 stars have a magnitude of 0.0, while the remaining 9,900 have a magnitude of +5.0. A weighted average calculation yields an integrated visual magnitude of approximately 5.0 for the cluster. The term is not defined in class materials or textbooks, leading to confusion among students. Further resources or formulas may be needed for a clearer understanding of this concept.
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A certain globular cluster has a total of 10^4 stars; 100 of them have MV=0.0, and the rest have MV=+5.0. What is the integrated visual magnitude of the cluster?


Nowhere in our class notes or textbook is the term "integrated visual magnitude" defined. Googling it, I find the term used, but not defined.


If I had to guess how to do this problem, I'd just do a weighted average:

M_{cluster}=\frac{(100*0.0)+(9900*5.0)}{10000}

M_{cluster}=4.95

Which when rounded for significant figures = 5.0
 
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See if these notes and examples help -

http://ottawa.rasc.ca/observers/an9811p9.html

I am a bit surprised that this is not covered in your textbook.
 
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I was also given this question and I tried clicking the link and it doesn't work. How would I go about starting this? We too didn't learn anything about integrated visual magnitude so I have no idea what to do with this. Is there some type of formula or something?
 
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