Water/Hycean Worlds & Oceanography

A Simplified Model for the Forced Libration of Icy Moons with Subsurface Oceans: Application to Enceladus and Mimas

By Keith Cowing

Status Report

astro-ph.EP

May 7, 2024

Filed under astro-ph.EP, Enceladus, forced librations, Icy Moon, Mimas, ocean, Saturn, subsurface ocean

A Simplified Model for the Forced Libration of Icy Moons with Subsurface Oceans: Application to Enceladus and Mimas — Illustration of the tidal action between a planet (Saturn) and its moon (Enceladus). Enceladus moves on a synchronized elliptical orbit, which makes its instantaneous orbital speed vary. At its closest point to Saturn, Enceladus rotates slower than it orbits, so the raised tide lies slightly behind the Enceladus-Saturn (dashed) line in the direction of Enceladus’s rotation. At its most distant point to Saturn, the opposite is true. As a result, the raised tide performs tiny oscillations called librations. — astro-ph.EP

In this work, we investigate a minimalist model capable of accurately replicating the forced librations of an icy moon with a subsurface ocean.

The model holds potential to predict the presence of a subsurface ocean through analysis of longitudinal librations.

We demonstrate that a two-layered model, with a prestressed icy crust and a fixed mantle cavity, can effectively model the librational behavior of icy moons. The proposed model is applied to model the longitudinal libration of Enceladus and Mimas, two medium-sized icy moons of Saturn.

Yeva Gevorgyan

Comments: 7 pages, 12 figures, submitted to MNRAS
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2405.03350 [astro-ph.EP] (or arXiv:2405.03350v1 [astro-ph.EP] for this version)
Submission history
From: Yeva Gevorgyan
[v1] Mon, 6 May 2024 11:01:54 UTC (1,674 KB)
https://arxiv.org/abs/2405.03350
Astrobiology,

Keith Cowing

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻

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