TY - JOUR
T1 - The role of interior dynamics and differentiation on the surface and atmosphere of lava planets
AU - Boukaré, Charles-Édouard
AU - Lemasquerier, Daphné
AU - Cowan, Nicolas B
AU - Samuel, Henri
AU - Badro, James
AU - Dang, Lisa
AU - Falco, Aurélien
AU - Charnoz, Sébastien
N1 - Funding: This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 101019965— SEPtiM). Parts of this work were supported by the UnivEarthS Labex program at Université de Paris and IPGP (ANR-10-LABX-0023 and ANR-11-IDEX-0005-02) and Natural Sciences and Engineering Research Council of Canada (RGPIN-2024-06174). Two-dimensional numerical computations were performed on the IPGP S-CAPAD/DANTE platform. D. Lemasquerier acknowledges the Texas Advanced Computing Center (TACC) at The University of Texas at Austin for providing HPC and visualization resources that have contributed to the research results reported within this paper (URL: http://www.tacc.utexas.edu). L.D. acknowledges support from the Banting Postdoctoral Fellowship program, administered by the Government of Canada and the Trottier Family Foundation.
PY - 2025/7/29
Y1 - 2025/7/29
N2 - Lava planets are rocky exoplanets that orbit so close to their host star that their dayside is hot enough to melt silicate rock. Their short orbital periods ensure that lava planets are tidally locked into synchronous rotation, with permanent day and night hemispheres. Such asymmetric magma oceans have no analogues in the Solar System and their internal dynamics and evolution are still poorly understood. Here we report the results of numerical simulations showing that solid–liquid fractionation has a major impact on the composition and evolution of lava planets. We explored two different interior thermal states. If the interior is fully molten, the atmosphere will reflect the planet’s bulk silicate composition, and the nightside solid surface is gravitationally unstable and constantly replenished. If the interior is mostly solid with only a shallow magma ocean on the dayside, the outgassed atmosphere will lack in Na, K and FeO, and the nightside will have an entirely solid mantle with a cold surface. We show that these two end-member cases can be distinguished with observations from JWST, offering an avenue to probe the thermal and chemical evolution of exoplanet interiors.
AB - Lava planets are rocky exoplanets that orbit so close to their host star that their dayside is hot enough to melt silicate rock. Their short orbital periods ensure that lava planets are tidally locked into synchronous rotation, with permanent day and night hemispheres. Such asymmetric magma oceans have no analogues in the Solar System and their internal dynamics and evolution are still poorly understood. Here we report the results of numerical simulations showing that solid–liquid fractionation has a major impact on the composition and evolution of lava planets. We explored two different interior thermal states. If the interior is fully molten, the atmosphere will reflect the planet’s bulk silicate composition, and the nightside solid surface is gravitationally unstable and constantly replenished. If the interior is mostly solid with only a shallow magma ocean on the dayside, the outgassed atmosphere will lack in Na, K and FeO, and the nightside will have an entirely solid mantle with a cold surface. We show that these two end-member cases can be distinguished with observations from JWST, offering an avenue to probe the thermal and chemical evolution of exoplanet interiors.
U2 - 10.1038/s41550-025-02617-4
DO - 10.1038/s41550-025-02617-4
M3 - Article
SN - 2397-3366
SP - 1
EP - 12
JO - Nature Astronomy
JF - Nature Astronomy
ER -