Title: The Sun in Time and Other Mysteries
Abstract: The theory of stellar structure and evolution is quite successful in predicting the evolution of stars like the Sun over their lifetime of billions of years. However, changes in the Sun that take place over decades have more societal relevance. These changes are governed by the solar activity cycle and not described by stellar evolution theory. While changes on the surface of the Sun have been studied for a very long time, internal changes were a mystery until helioseismic data over different epochs of the solar cycle became available. We now have helioseismic data over two solar cycles that have allowed us to “see” the changes that take place within the Sun. In this talk I shall describe what we have learned about changes in the solar interior. I shall also give an update on the controversy surrounding solar metallicity, an issue that affects the broader astrophysics community.