The observation and characterization of transiting exoplanet atmospheres is currently one of the fastest growing fields in astronomy. Over the last 15 years we have progressed from having photometric observations of a handful of planets, to the first spectroscopic population studies of favourable hot Jupiter targets with the Hubble Space Telescope, and now to the unprecedented detail and quality of JWST data. The tool of choice for interpreting transit spectra is a retrieval scheme. These combine relatively simple, usually 1D, radiative transfer models with a sampling algorithm. Individual computations must be fast, since potentially millions are required for a solution; we therefore strike a balance between realistic (but complex and therefore slow) models, and oversimplified models that are fast but ignore important physics. As the information content of observations increases, some approximations are no longer valid and our approach has to change. During this talk, I will present some of the latest observations from the JWST Transiting Exoplanets Early Release Science Team and other programmes I am involved in, including the complete transmission spectrum of WASP-39b, the phase curve of WASP-43b, and the transmission spectra of WASP-107b and WASP-121b. I will discuss what we have been able to learn from these measurements, what impact this has had on the way we design our models, and what the likely future directions are for transiting exoplanet research with JWST. 

recording: www.youtube.com/watch