2021/10/28 by Caroline Dorn, Tim Lichtenberg
Physics and Astronomy · #Astro and Planetary Science #Astrobiology #Astronomy #Astronomy and Astrophysical Research #Exoplanet #Geochemistry #Geology #Geophysics #Magma #Mantle (geology) #Oceanography #Petrology #Physics #Planet #Population #RADIUS #Stellar, planetary, and galactic studies #Volcano #Water mass #astro-ph.EP
paper · pdf · doi:10.3847/2041-8213/ac33af
published in The Astrophysical Journal Letters 922(1), L4 (IOP Publishing) · 13 pages, 5 figures, ApJL, video summary can be found here: https://bit.ly/DornLichtenberg21video
arxiv created 2021/10/28 · openalex publication_date 2021/11/01 · arxiv updated 2021/11/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Abstract We demonstrate that the deep volatile storage capacity of magma oceans has significant implications for the bulk composition, interior, and climate state inferred from exoplanet mass and radius data. Experimental petrology provides the fundamental properties of the ability of water and melt to mix. So far, these data have been largely neglected for exoplanet mass–radius modeling. Here we present an advanced interior model for water-rich rocky exoplanets. The new model allows us to test the effects of rock melting and the redistribution of water between magma ocean and atmosphere on calculated planet radii. Models with and without rock melting and water partitioning lead to deviations in planet radius of up to 16% for a fixed bulk composition and planet mass. This is within the current accuracy limits for individual systems and statistically testable on a population level. Unrecognized mantle melting and volatile redistribution in retrievals may thus underestimate the inferred planetary bulk water content by up to 1 order of magnitude.