It refers to their spectral type.
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Using the classification system of OBAFGKM for star color (from blue to white to orange-red), Antares is an "M".
LT
Oh Be A Fine Girl, Kiss Me . . . Additional spectral categories have been defined for many stars, designated R, N, and S. These can easily be added to the mnemonic phrase above: . . . . . Right Now, Smack .
Phenotype.
To do with the stars, from the Latin stella, a star
Using the classification system of OBAFGKM for star color (from blue to white to orange-red), Antares is an "M".
OBAFGKM
LT
the stars and stripes refer to the flag, smart one!
Oh Be A Fine Girl, Kiss Me . . . Additional spectral categories have been defined for many stars, designated R, N, and S. These can easily be added to the mnemonic phrase above: . . . . . Right Now, Smack .
Three characteristics to classify stars are their luminosity, size, and color or surface temperature.
atoms
the light radiated from the stars
The spectral type of a star (OBAFGKM) are based on spectral emissions and have no real relationship with size.
production of light
size
Phenotype.