Exoplanet atmosphere models

Forward and retrieval models used to interpret exoplanet transmission, emission, and reflection spectra. The dominant frameworks couple radiative transfer with chemical-equilibrium or kinetic chemistry, increasingly with self-consistent thermal profiles.

Known gaps

• Clouds and hazes — most production models are cloud-free or use parameterized grey clouds because real cloud microphysics (nucleation, sedimentation, lateral patchiness) is computationally expensive. The 2026 src-jwst-ice-clouds-exoplanet-2026-04 result on water-ice-clouds in epsilon-indi-ab is one of the most explicit cases where this gap demonstrably misreads atmospheric composition.
• Photochemistry false-positives — abiotic O₂ and CH₄ pathways are still being mapped (see src-oxygen-false-positive-biosignatures-2026-03).
• 3D dynamics — most retrievals assume 1D atmospheres; rotation, day-night terminator effects, and patchy cloud decks are open problems. The 2026 limb-resolved JWST study of hot-jupiter wasp-94ab is the strongest case yet that terminator/limb asymmetry breaks 1D blended-limb retrievals: separating the cloudy morning limb from the clear evening limb corrected the planet’s oxygen/carbon abundance from “hundreds of times” to ~5× Jupiter (src-jwst-wasp-94ab-weather-cycle-2026-05). On wasp-121b, the observed dawn–dusk asymmetry amplitude exceeded model predictions, attributed to unmodeled silicate clouds at the morning terminator (src-jwst-wasp-121b-dawn-dusk-2026-06).

Related pages

• water-ice-clouds
• direct-imaging
• jwst
• src-jwst-ice-clouds-exoplanet-2026-04
• src-jwst-toi-1130b-atmosphere-2026-05
• src-jwst-biosignature-prospects-2025
• src-oxygen-false-positive-biosignatures-2026-03
• src-biosignature-gas-flux-inference-2026-04
• src-sciencedaily-forbidden-exoplanet-atmosphere-2026-04 — toi-5205-b stress-tests the bulk-tracks-atmosphere assumption: bulk planet is ~100× more metal-rich than the visible atmosphere (interior/atmosphere decoupling).
• src-aas-nova-wd-0806b-atmosphere-2026-04 — wd-0806b yields the first observational evidence that vertical mixing (K_zz) weakens with altitude — argues against the single-K_zz simplification standard in 1D retrievals.
• src-jwst-wasp-94ab-weather-cycle-2026-05 — wasp-94ab shows a repeating morning-cloud/evening-clear weather cycle; demonstrates that limb-blended retrievals systematically bias inferred metallicity for hot Jupiters (also seen on WASP-39b, WASP-17b).
• src-jwst-wasp-121b-dawn-dusk-2026-06 — wasp-121b dawn–dusk asymmetry amplitude exceeded predictions; unmodeled morning-terminator silicate clouds.