[astro-ph.EP] Cryovolcanism is a fundamental geodynamical process that has been observed on several icy moons. Europa stands out as a primary target for investigating potential cryovolcanic activity and its role in shaping icy moon surfaces.
This work characterizes the physical state of ascending cryomagma and evaluates the relevance of terrestrial analogues to explain Europa’s surface features. After investigating cryomagma depressurization, we developed CryoPy, a numerical model based on Smoothed-Particle Hydrodynamics (SPH) for computational fluid dynamics and heat transfer.
We simulated flow propagation and surface cooling using this model. Our simulations show that snow is a relevant physical analogue for cryolava, as the resulting flows closely match the smooth plains observed by Galileo in both extent and morphology.
Additionally, we established the temporal thermal signatures of these events. Such active cryovolcanic events are within the detection limits of, primarily, the E-THEMIS infrared imager, providing a predictive framework for the Europa Clipper mission.
Three possible fracture geometries through Europa’s crust, presented in a vertical cross-sectional view. The ice is represented in dark blue with crosses, while the cryolava is indicated in light blue hatched lines. These fracture systems establish a physical connection between a pressurized liquid water reservoir beneath the moon’s surface and the crust itself, in accordance with the scenario proposed by Lesage et al. (2020). Each geometry corresponds to a specific hydrodynamic regime: case (1) shows a simple conduit without obstacles, case (2) presents a more complex geometry where the fluid encounters obstacles on its way to the surface, and case (3) represents porous fractures allowing the fluid to seep to the surface. In all cases, to facilitate reasoning, reference points are indicated: “A” at the top of the reservoir beneath the surface and “B” at the conduit outlet. The horizontal sections of the conduit, at A and B, are denoted as 𝑆𝐴 and 𝑆𝐵 , respectively. The total depth 𝐻 considered by Lesage et al. (2020) ranges between 1 km and 10 km. Panel (4) outlines the scenario adopted in this work: the depressurization experienced by the liquid water, as it approaches the surface, rapidly triggers partial vaporization into a mixture of water vapor and ice grains, similar to snow. In panel (4), the conduit is generic and can represent any combination of the cases illustrated in the previous panels (1 to 3). Bastien Bodin (LEATP), Daniel Cordier (LPGN), Ashley Gerard Davies (JPL) — [astro-ph.EP]
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2609.27562 [astro-ph.EP] (or arXiv:2609.27562v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2609.27562
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Submission history
From: Bastien Bodin
[v1] Wed, 23 Sep 2026 08:48:00 UTC (9,412 KB)
https://arxiv.org/abs/2609.27562
Astrobiology,
