Institute for Advanced Study/Princeton University Joint Astrophysics Colloquium

Red supergiants (RSGs) are the helium-fusing descendants of moderately massive (10-25Mo) stars. As the coldest and largest (in physical size) members of the massive star population, these evolved stars serve as ideal "magnifying glasses" for scrutinizing our current understanding of massive stars and their role as supernova progenitors. RSGs are the observationally-confirmed progenitors of Type II-P, an intermediate evolutionary phase in the lifetimes of some stripped-envelope SN progenitors, and a crucial step in the formation and population statistics of massive interacting binaries (including those that will ultimately produce compact object binaries and gravitational waves). This talk will provide an overview of our field's current knowledge of RSGs, identify some of the most pressing open questions about these stars and their role as supernova progenitors, and consider the importance of RSGs in the coming decade as the next generation of observatories comes online.