Lecture 25. B. Luminosity Classes
Lecture 25. B. Luminosity Classes
Knowing a star's spectral class
(O,B,A,F,G,K,M) is not enough to specify its luminosity:
-- the branches above and below main sequence
share spectral class, but not luminosity!
Luminosity classes delineate which branch a star lies on...
- Ia. Brightest Supergiants
- Ib. Less Luminous Supergiants
- II. Bright Giants
- III. Giants
- IV. Subgiants
- V. Main Sequence -- our Sun is G2 V.
DON'T memorize these, but know of them and where to find them!