From photons to storms: Revealing the 3D structure of giant exoplanet atmospheres

The solar system's giant planets, Jupiter and Saturn, host atmospheres with clear belts, cloudy bands, and storms like the Great Red Spot. They represent the class of cool, isolated giant planets. For a full view of giant planet atmospheres we must study the known exoplanet population over a wide range of orbits, temperatures, and spins. However, exoplanets are too far away to resolve them directly.The James Webb Space Telescope is changing this: time-resolved spectra probe the atmospheres of rotating wide-orbit planets, whose light curves reveal active weather. The Extremely Large Telescope's METIS and ANDES instruments will study giant planets from close to wide orbits at high spectral resolution, probing winds through Doppler shifts, allowing us to constrain flow and temperature structures.In spite of these amazing prospects, there is no framework to properly fit JWST or future ELT data. State-of-the-art techniques are prohibitively slow, preventing hypothesis testing. This is a fundamental challenge that needs to be resolved - otherwise we cannot use the information encoded in our data.With the VORTEX project I will develop the machinery to map the 3D, dynamical atmospheres of giant exoplanets, from strongly irradiated to the most isolated ones. The modeling challenge will be addressed through a feedback between novel machine learning inference methods and hydrodynamical models. Our project will answer the three questions: (i) what are the properties, scales and lifetimes of storms on isolated planets? (ii) how do flows transport gas on irradiated planets? (iii) how do atmospheres of planets on eccentric orbits react to changing irradiation?VORTEX will have a long-lasting impact by enabling the 3D interpretation of exoplanet spectra. Answers to the questions above will reveal which processes govern the 3D atmospheres of exoplanets. Our methods will pave the way for analyzing similarly complex astronomical datasets recorded with the largest telescopes.