Mass to Light Ratio for Dwarf Galaxies

AI Thread Summary
The discussion focuses on determining the mass-to-light ratio for dwarf spheroidal galaxies using parameters such as distance, size, absolute magnitude, and velocity dispersion. While some participants express skepticism about the reliability of mass-to-light ratios, others reference research that suggests these ratios can be accurately measured through careful analysis of mass profiles and direct light output. The general consensus is that mass-to-luminosity ratios are derived from galactic surveys and can provide approximate values, though they may not be entirely reliable. The conversation highlights the ongoing debate regarding the accuracy of these measurements in astrophysics. Ultimately, understanding the mass of dwarf galaxies remains a complex challenge in the field.
nik6
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Hi,

I'm working on a project on dwarf spheroidal galaxies. Is there a way to get a mass-to-light ratio knowing the distance to the galaxy, its size, and maybe some other parameters like the absolute magnitude or velocity dispersion?

In the end, I'm trying to figure out their masses using this information.

Thanks!
 
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Mass to light ratio is more conjecture than theory. I would not trust any conclusions.
 
Alright I'll keep that in mind, thank you. Any advice on how to get mass from luminosity?
 
It is a generalization based on mass - luminosity ratios derived from galactic surveys. It is approximately accurate.
 
Chronos,

When i read papers like this one:
http://arxiv.org/abs/0708.0010
It seems like a fairly careful measurement of the mass profiles of several dwarf galaxies, and of course the light output can be measured directly, so the conclusion that dwarf galaxies have mass/light ratios of 10's to 100's seems sound. Why do you think it is just conjecture?
 

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