What fraction of the stars in our galaxy are red giants, white dwarfs etc?
The breakdown is about as follows.
Class.....Type...............Fraction..........Ratio...... I Supergiants 0.00000001 1 II Bright Giants 0.000005 20 III Giants 0.0004 40,000 IV Sub-Giants 0.0010 100,000 V Main Sequence 0.0034 340,000 VI Sub-Dwarfs 0.0035 350,000 VII Dwarfs 0.0129 1,290,000 .........................................................
where the 'Fraction' is the number of these stars near the Sun per cubic parsec. Another way of looking at this is the 'Ratio' column where we see that for every single supergiant like the star Betelgeuse, there are 340,000 Main Sequence stars like the Sun and Vega. There are also a heck of a lot of dwarf stars out there including red dwarfs and white dwarfs out there! If you look at a list of nearby stars within 25 parsecs of the Earth, you will be impressed by how many faint red dwarfs there are.
Copyright 1997 Dr. Sten Odenwald
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