Molecules in Exoplanet Atmospheres

Extrasolar planets provide a unique and powerful laboratory for studying the chemistry of planetary systems. By measuring chemical abundances in exoplanet atmospheres we aim to constrain the conditions at the planets’ birth and over their evolutionary history, understand the unique chemical processes that shape their present-day conditions, and ultimately identify the signatures of life on other worlds. I will present the current status of observations to measure the chemical composition of exoplanet atmospheres and the theoretical context for those results. I will highlight recent results from JWST and ground-based ELTs, which identify a whole host of molecular, atomic, and ionic species, as well as aerosols (clouds and haze); and I will discuss the implications of these ground-breaking measurements. I will conclude with a forward-looking view of where exoplanet atmospheric characterization efforts are heading over the next 5-10 years.