Organizing the Family of Stars: The Hertzsprung-Russell Diagram
We know:
Stars have different temperatures, different luminosities, and different sizes.
To bring some order into that zoo of different types of stars: organize them in a diagram of
Luminosity
versus
Temperature (or spectral type)
Text Box: Luminosity
Luminosity
Temperature
Spectral type: O    B    A    F    G    K    M
Hertzsprung-Russell Diagram
Text Box: or
or
Text Box: Absolute mag.
Absolute mag.
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