Lecture 25: A Tale of Two Galaxies, The Milky Way and Andromeda

Andromeda is the nearest bright spiral galaxy to the Milky Way, and a near twin in terms of stellar and gas content. This lecture discusses the idea of stellar populations and chemical evolution in galaxies as determined by combining observations from within (the Milky Way) and without (Andromeda). At the end, two other features of these galaxies, their supermassive central black holes, is introduced, setting up a question to be addressed in later lectures. Recorded 2006 February 9 in 1008 Evans Laboratory on the Columbus campus of The Ohio State University.