ESA's Ariel Space Telescope

ESA’s mission Ariel, Atmospheric Remote-sensing Infrared Exoplanet Large-survey, is an upcoming dedicated telescope that will study 1000s of exoplanet atmospheres, from small rocky worlds to large gas giants. Ariel will provide high-quality observations to constrain the chemistry, reveal the presence of clouds, and monitor how weather conditions on these planets change over time. Currently under construction, Ariel is planned to be launched at the end of the decade.

The mission’s primary goal is to uncover the physical and chemical diversity of exoplanetary atmospheres and to understand the processes that govern their formation and evolution. By observing hundreds of exoplanets with consistent instrumentation and methodology, the Ariel team hopes to uncover chemical trends that trace the origins of planets and explain how they have formed: this objective is not achievable with any other single-target missions. The homogeneous Ariel dataset will allow us to explore correlations between atmospheric properties, planetary characteristics, and stellar environments—shedding light on the connections between planet formation, migration, and atmospheric composition.

Our group has been deeply involved in Ariel since 2018. We contributes to the scientific preparation of the mission through modeling and retrieval studies that help interpret its forthcoming observations. Members of our team leds various Ariel working groups: Atmospheric retrieval, JWST/Ariel synergies. We work on developing and refining atmospheric models, radiative transfer tools, and retrieval frameworks tailored to Ariel’s spectral capabilities: our retrieval code TauREx is heavily used by the Ariel consortium. These efforts aim to not only guide the mission's scientific objectives, but also to ensure that once data arrive, the community can robustly infer atmospheric compositions, temperature profiles, and cloud properties. Ariel’s legacy will be a transformative understanding of exoplanet atmospheres, built on the foundation of both precise measurements and physically grounded models.