Exploring the Diversity of Distant Worlds: Characterizing Exoplanets and their Atmospheres

Characterizing a planetary system gives us a single snapshot of their evolution. Although we will never get the same level of details for an exoplanets as we do for Solar System bodies, the large diversity of exoplanets provide thousands of study cases to refine their origins theories and theories of how their climate is shaped by their environment. Given their short orbits, Hot Jupiters are some of the best-characterized exoplanets to this day. Yet, there is still no consensus on their origin and their atmospheric properties remain poorly understood. Nonetheless, we can get observational insights into these planets and their atmosphere at various stages of their evolution. Recently decommissioned, the Spitzer Space Telescope provided extremely valuable observations of thermal emission of close-in exoplanets and later served as a microlens parallax satellite to study exoplanets beyond the snow line. In this talk, I will present about what we have learned from phase curve observations of close-in planets, including seasons on eccentric hot Jupiters caught in the act of migrating into short-period orbits, circulation patterns on synchronously-rotating hot Jupiters, and lastly, the fate of short-period planets as well as how it ties into the Spitzer Microlensing Campaign. Finally, I will then discuss the continuation of Spitzer’s legacy with JWST.