Princeton University Extrasolar Planet Discussion Group

Over the past 30 years, nearly 6000 exoplanets have been discovered, revealing a remarkable diversity of planetary systems. Essential information about the formation of these systems can be found in their current architectures, as they serve as a signature of their dynamical evolution. Most of the knowledge we have about architectures comes from the study of stellar obliquities---the angle between the stellar spin axis and the planet's orbital normal---in hot Jupiter systems. However, hot Jupiters are relatively rare, with an occurrence rate of ~1%, highlighting the need to explore architectures in a broader range of planetary systems. In this talk, I will present recent efforts to extend obliquity measurements beyond hot Jupiters, focusing on warm Jupiters and Neptunes. These efforts have revealed that the obliquity distributions of different planetary populations vary, suggesting distinct formation histories. Finally, I will discuss prospects for measuring mutual inclinations---the angle between planetary orbits within a system---using future Gaia astrometric data. I will show that these measurements have the potential to provide deeper insights into the formation and evolution of a larger and more diverse sample of planetary systems.