Offered autumn odd-numbered years. Prereq., ASTR 132N or ASTR 142N, and PHSX 207N- PHSX 208N or PHSX 217N- PHSX 218N, and prereq., or coreq., M 273. Detailed application of physical laws to determine the nature of the stars; analysis of stellar spectra and atmospheres; solar astrophysics; structure of stars and their evolution.