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Titan is an ocean world with a dense atmosphere, where photochemistry produces complex organic molecules that fall to the surface. An important astrobiological question is whether this material can mix with water and form molecules of biological interest. Large impacts heat the moon's subsurface and create liquid water melt pools. A recent study investigated impacts into Titan's clathrate‐covered ice shell. Methane clathrates are stable at Titan's surface conditions and have low thermal conductivity, making them efficient insulators that can lead to steep thermal gradients and a thin stagnant lid. The authors showed that the clathrate layer thickness primarily influences the melt distribution, while its volume is governed by the impactor size. Here, we investigate the fate of melt formed during an impact into a clathrate‐covered ice shell. Our results show two different behaviors: in cases when less melt is produced, the subsurface melt pool remains close to the surface and freezes on timescales ≲25 kyr; in cases when larger volumes of melt are produced, a downward‐oriented transport of the molten material occurs. As it descends, part of the melt freezes but some may reach the ocean within a few kyr under certain conditions; vertical impacts, high surface porosity, low viscosity, and tidal heating all favor this surface‐to‐ocean exchange. While providing insights on parameters that allow a subsurface melt pool to remain liquid beneath a Selk‐sized crater for a few kyr, this study suggests that Dragonfly may be able to sample melt deposits where organics reacted with liquid water to produce biomolecules. Titan, Saturn's largest moon, harbors a subsurface ocean beneath its ice shell. The moon also has an atmosphere, which is rich in large organic molecules that settle onto its surface. When atmospheric methane reacts with surface water ice, it forms methane clathrate. A clathrate layer atop Titan's ice shell affects the formation of Titan's impact craters, as it is both stronger than ice and a better insulator. Here, we study the effect of this clathrate layer on the formation and subsequent fate of melt pools produced by impacts on Titan. We investigate whether the melt descends through the ice shell to reach the ocean or remains near the surface and freezes. Our results show only a limited range of scenarios where impact melt reaches the ocean. In the majority of models, impact melt freezes near the surface within short timescales, ranging from a few thousands to tens of thousands of years. This implies that surface organic molecules may have interacted with subsurface melt pools. These results provide a positive outlook for NASA's Dragonfly mission, which will explore Titan's Selk crater in search of organic materials that have reacted with water to potentially form molecules of biological interest. We studied the evolution of impact melt pools in Titan's ice shell using numerical simulations of two‐phase thermal convectionWhile most melt pools never reach the ocean, we observe surface‐to‐ocean exchange in a small part of the investigated parameter spaceOur results suggest that Dragonfly may be able to sample melt deposits where organics reacted with liquid water to produce biomolecules We studied the evolution of impact melt pools in Titan's ice shell using numerical simulations of two‐phase thermal convection While most melt pools never reach the ocean, we observe surface‐to‐ocean exchange in a small part of the investigated parameter space Our results suggest that Dragonfly may be able to sample melt deposits where organics reacted with liquid water to produce biomolecules

Enceladus is a dynamic icy moon of Saturn and a leading target for future planetary missions focused on the search for life beyond Earth. For such missions, instruments that can provide geophysical and geochemical context for ice shell and ocean processes are critical to evaluate whether conditions are suitable for life and biosignature detection. Radar sounding is a powerful geophysical technique to probe the thermophysical and chemical properties of icy moons, like Enceladus, and to investigate the subsurface context for the exchange of material and energy between their subsurface oceans, ice shells, and plumes. To inform the scientific potential and instrument performance demands of such a radar‐sounding investigation of Enceladus' ice shell, we adapt and extend previous radar attenuation analysis done for Europa to the configuration and conditions of Enceladus. We also discuss how attenuation (both as an obstacle for the detection of ice shell reflectors and as a signal itself) can help constrain the thermal, physical, and chemical configuration of Enceladus' ice shell and reveal the processes governing the moon's ocean/shell/plume system. Enceladus, a tiny icy moon of Saturn, has been attracting attention since the discovery of its spectacular water jet activity. The jets, sampling the moon's hidden deep ocean, have revealed conditions favorable for the existence of life below the cold outer ice shell. Understanding the long‐term persistence of the ocean, the jets, and their connection to the ice shell and ocean requires reliable knowledge of the shell's physical, thermal, and chemical properties. Ice penetrating radar is a powerful tool for studying ice shells in the planned missions to Jupiter's icy moons. In this paper, we expand and adapt the radar‐based approach to Enceladus in light of the established constraints on the shell's structure and chemistry. We find that although the shell's chemical composition makes direct radar detection of the ice‐ocean interface challenging, the shell's thermal structure enables constraining the thickness—and potentially chemistry—by future missions using echoes from water within the shell. We explore radar attenuation within Enceladus' ice shell as a function of its chemistry using a 3D model of its shape and thermal structureDirect radar detection of the ice‐ocean interface is improbable for chloride‐rich shells except for the thin south‐polar regionThe NH3eutectic isotherm is a comparatively easy‐to‐detect interface, with the potential to constrain the shell thickness and composition We explore radar attenuation within Enceladus' ice shell as a function of its chemistry using a 3D model of its shape and thermal structure Direct radar detection of the ice‐ocean interface is improbable for chloride‐rich shells except for the thin south‐polar region The NH3eutectic isotherm is a comparatively easy‐to‐detect interface, with the potential to constrain the shell thickness and composition

Enceladus is a small icy moon of Saturn with active jets of water emanating from fractures around the south pole, informally called tiger stripes, which might be connected to a subsurface water ocean. The effect of these features on periodic tidal deformation of the moon has so far been neglected because of the difficulties associated with implementation of faults in continuum mechanics models. Here we estimate the maximum possible impact of the tiger stripes on tidal deformation and heat production within Enceladus's ice shell by representing them as narrow zones with negligible frictional and bulk resistance passing vertically through the whole ice shell. Assuming a uniform ice shell thickness of 25 km, consistent with the recent estimate of libration, we demonstrate that the faults can dramatically change the distribution of stress and strain in Enceladus's south polar region, leading to a significant increase of the heat production in this area. The presence of faults can significantly change the distribution of stress and strain in Enceladus's south polar region (SPR)The deformation induced by faults leads to local increases of heat flux by a factor of 10 and a twofold increase in SPR on averageThe effect of the faults on stress and strain is limited to SPR and is negligible at distances larger than 40 degrees from the south pole