Stellar types
Early-type supergiant stars
O stars
OB stars
Early-type emission stars
Early-type variable stars
A stars
B stars
Faint blue stars
Hot stars
Early type stars
Early-type stars
Hot, luminous stars of spectral type O, B, A, and F0 to F5. They were originally thought, wrongly, to be at an earlier stage of evolution than late-type stars.