Christoph Mordasini

Postdoctoral position in exoplanet atmospheres at the University of Bern This is a fully funded postdoc in the Space Research and Planetary Sciences group at the University of Bern, Switzerland, working on the atmospheres of transiting sub-Neptunes. The project is part of the SNSF-funded Exo-Neptune Census starting grant led by Assistant Professor Hugh Osborn. The research focuses on population-level analysis of sub-Neptune radii, masses, and atmospheres to understand the formation, composition, and evolution of these planets. A major part of the work will involve extracting atmospheric volatile abundances and bulk planetary volatile compositions from JWST observations. The postdoc may also contribute to the IN/AT-SYNC JWST large programme and help obtain additional JWST transmission spectra of sub-Neptunes. Ideal applicants should have strong experience with Bayesian statistical methods, exoplanet transit modelling, atmospheric physics, and JWST time-series/spectroscopic analysis. Knowledge of atmospheric chemistry, radiative transfer, and retrieval methods is especially relevant. The post also values theoretical expertise linking sub-Neptune interiors and atmospheres. The position is 100% fixed-term, funded for 2 years with a possible 1-year extension. It includes competitive salary, travel support for conferences and research visits, and standard benefits such as child allowance and maternity/paternity leave. Postdocs are expected to assist with teaching and may supervise Masters projects and mentor PhD students. Application deadline: 2026-08-31 at 23:39 CEST. Apply with a cover letter, academic CV, PhD diploma if available, two academic references, and your earliest possible start date. Applications can be submitted by email to hugh.osborn@unibe.ch or through the online application form.