16
Luminosity Classes
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•Ia Bright supergiant
•Ib Supergiant
•II Bright giant
•III Giant
•IV Subgiant
•V Main sequence star
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•white dwarfs not given
Roman numeral
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•Sun: G2 V
•Rigel:  B8 Ia
•Betelgeuse: M2 Iab
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From our text:  Horizons, by Seeds