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- Thread starter Barnak
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I already searched (especially Wikipedia) and didn't found the % I was looking for. The only document (a picture in some PowerPoint document !) gave the percentage of stars of given masses :

41% for M < 0.25 M_Sol

28% for 0.25 M_Sol < M < 0.5 M_Sol

19% for 0.5 M_Sol < M < 1 M_Sol

8% for 1 M_Sol < M < 2 M_Sol

3% for 2 M_Sol < M < 4 M_Sol

~1% for M > 4 M_Sol

The trouble is that the document isn't clear and precise enough about the source of this data (where does it come from ?)

I also need something similar about the spectral classes.

I simply need more, so this is why I'm asking for some help on this subject.

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- #5

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http://en.wikipedia.org/wiki/Stellar_classification

we can find spectral class populations in % but only for the main sequence stars. I need something more general. Also, the Wikipedia article doesn't say anything about populations sorted by masses.

- #6

Chronos

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Check Vizier, they have spectral survey databases.

- #7

Vanadium 50

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Fundamentally the problem is bias - it's easy to see big, bright, blue stars, so counting what you see in the sky gives you a sample that is biased, big, bright and blue.

- #8

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Q : How can we know if a randomly picked star is in the main sequence ?

More precisely, suppose I have the following innformations :**Radius**, **Luminosity**, **Absolute Magnitude**, **Spectral class** and **surface temperature**. Is there a simple mathematical procedure to say if it's a main sequence star ?

More precisely, suppose I have the following innformations :

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