The Rocky Planet Picture Show: Implementation of Surface Reflection and Emission in POSEIDON with Application to and Interpretation of JWST Data

arXiv:2605.00700 · astro-ph.EP, astro-ph.IM · Submitted 2026-05-01 · Read on arXiv

Elijah Mullens, Ryan J. MacDonald, Marina E. Gemma, Ishan Mishra, Esteban Gazel, Nikole K. Lewis

astro-ph.EP, astro-ph.IM

Submitted: 2026-05-01

Comments: 16 pages (main text), 24 pages (appendix), 7 figures, submitted to PSJ. This paper coincides with the public release of POSEIDON v1.4

Code: https://github.com/MartianColonist/POSEIDON

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Terminology

• Core — 10× in this paper · explained in 2 episodes
• Abundance — 6× in this paper · explained in 1 episode
• Habitable Worlds Observatory — 4× in this paper
• Spectral Signature — 4× in this paper · explained in 2 episodes
• Total Alkali-Silica — 3× in this paper
• Adam — 2× in this paper · explained in 2 episodes
• Trace — 2× in this paper · explained in 2 episodes
• Transmission spectroscopy — 2× in this paper · explained in 2 episodes
• Active Regions — 1× in this paper · explained in 1 episode

Sources

• Detecting Surface Liquid Water on Exoplanets
• Identifying rocky planets and water worlds among sub-Neptune-sized exoplanets with the Habitable Worlds Observatory
• Wavelength Requirements for Life Detection via Reflected Light Spectroscopy of Rocky Exoplanets
• Coupled atmospHere Interior modeL Intercomparison (CHILI) Protocol Version 1.0: A CUISINES Intercomparison Project of Magma Ocean Models
• A dark, bare rock for TOI-1685 b from a JWST NIRSpec G395H phase curve
• Impact of Subsurface Temperature Gradients on Emission Spectra of Airless Exoplanets: the Solid-state Greenhouse and Anti-Greenhouse
• Mantle Convection and Nightside Volcanism on Lava World K2-141 b
• Evidence for an Atmosphere on the Ultra-Short Period super-Earth HD 3167 b
• What's Inside Matters: The Effect of Oxygen Fugacity and Initial Volatile Abundance on the Atmospheres of the TRAPPIST-1 Planets
• A Thick Volatile Atmosphere on the Ultrahot Super-Earth TOI-561 b
• Sensitivity of Dry Lava Planet Atmospheric Emission Spectra to Changes in Lava Compositions
• The Thermal Emission Spectrum of the Nearby Rocky Exoplanet LTT 1445A b from JWST MIRI/LRS
• Characterizing the Dynamics and Chemistry of Transiting Exoplanets with the Habitable World Observatory
• Identifying Surface Degeneracies in Single-Visit Reflected Light Observations of Modern Earth using the Habitable Worlds Observatory

Related papers

• PDS 70 c and SR 12 c: Observational Constraints on Giant-Planet and Satellite Formation
• Two-stage disruption of resonant chains
• Detectability of resolved hydrogen lines from the accretion shock at gas giants and their CPDs
• Binary-lens Microlensing Degeneracy: Impact on Planetary Sensitivity and Mass-ratio Function
• Atmospheric escape fractionates secondary but not primary atmospheres
• The Occurrence Rate of Nearby Planetary Companions to Hot Jupiters