| Title: |
Evolution of Impact Melt Pools on Titan |
| Authors: |
Kalousová, Klára; Wakita, Shigeru; Sotin, Christophe; Neish, Catherine D.; Soderblom, Jason M.; Souček, Ondřej; Johnson, Brandon C. |
| Contributors: |
Laboratoire de Planétologie et Géosciences UMR_C 6112 (LPG); Le Mans Université (UM)-Université d'Angers (UA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST); Nantes Université - pôle Sciences et technologie; Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie; Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ) |
| Source: |
Journal of Geophysical Research: Planets ; https://insu.hal.science/insu-04841460 ; Journal of Geophysical Research: Planets, 2024, 129, ⟨10.1029/2023JE008107⟩ |
| Publisher Information: |
CCSD |
| Publication Year: |
2024 |
| Collection: |
Université de Nantes: HAL-UNIV-NANTES |
| Subject Terms: |
impact; melt pool; two-phase flow; Dragonfly; melt transport; Titan; [SDU]Sciences of the Universe [physics] |
| Description: |
International audience ; 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. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| Relation: |
BIBCODE: 2024JGRE.12908107K |
| DOI: |
10.1029/2023JE008107 |
| Availability: |
https://insu.hal.science/insu-04841460; https://insu.hal.science/insu-04841460v1/document; https://insu.hal.science/insu-04841460v1/file/JGR%20Planets%20-%202024%20-%20Kalousov%C3%A1%20-%20Evolution%20of%20Impact%20Melt%20Pools%20on%20Titan.pdf; https://doi.org/10.1029/2023JE008107 |
| Rights: |
http://creativecommons.org/licenses/by/ ; info:eu-repo/semantics/OpenAccess |
| Accession Number: |
edsbas.4C173440 |
| Database: |
BASE |