Committee: Sara Seager (Chair), Erin Kara, Andrew Vanderburg

Resolving the Mysteries of Highly Irradiated Planets
Modern exoplanet science has an observational bias towards short-period planets. Among other things, these planets tend to be highly irradiated, either thermally resulting in high equilibrium temperatures and/or through high energy FUV/Xray radiation. The resulting planets exhibit a diverse array of physical characteristics unlike those seen on Earth. I present a collection of works broadly encompassed by the theme of understanding highly irradiated planets and a set of new techniques I develop to further analysis of these strange worlds. First I discuss observations of Upsilon Andromedae b, a non-transiting planet I have observed the atmosphere of for the first time, and Venus, Earths twin sister that turned out so different. Each of these observations is enabled by a new method I introduce for that class of analyses. I then present my work on radiation-hydrodynamics simulations of atmospheres subject to intense high energy radiation, for which I have developed a new simulation code with a unique purpose.

Best of luck to Nicholas!