7 stelar classifications

1. Class O - > 33,000K (Zeta Ophiuchi)
2. Class B - 10,500 - 30,000K (Rigel)
3. Class A - 7,500 - 10,000K (Altair)
4. Class F - 6,000 - 7,200K (Procyon A)
5. Class G - 5,500 - 6,000K (Sun)
6. Class K - 4,000 - 5,250K (Epilon Indi)
7. Class M - 2,600 - 3,850K (Proxima Centauri)