Exploring the evolution of lava planets using planet-resolving models
Copernicus Publications (2024)
Distinguishing Oceans of Water from Magma on Mini-Neptune K2-18b
The Astrophysical Journal Letters American Astronomical Society 962:1 (2024) L8-L8
Abstract:
Mildly irradiated mini-Neptunes have densities potentially consistent with them hosting substantial liquid-water oceans ("Hycean" planets). The presence of CO2 and simultaneous absence of ammonia (NH3) in their atmospheres has been proposed as a fingerprint of such worlds. JWST observations of K2-18b, the archetypal Hycean, have found the presence of CO2 and the depletion of NH3 to 4 μm region, where CO2 and CO features dominate: magma ocean models suggest a systematically lower CO2/CO ratio than estimated from free-chemistry retrieval, indicating that deeper observations of this spectral region may be able to distinguish between oceans of liquid water and magma on mini-NeptunesTemperature-chemistry coupling in the evolution of gas giant atmospheres driven by stellar flares
ArXiv 2306.03673 (2023)