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