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arXiv · 2004.01109

Tidal friction in satellites and planets. The new version of the creep tide theory

Abstract

Paper on the creep tide theory and its applications to satellites and planets with emphasis on a new set of differential equations allowing easier numerical studies. The creep tide theory is a new paradigm that does not fix a priori the tidal deformation of the body, but considers the deformation as a low-Reynolds-number flow. The evolution under tidal forces is ruled by an approximate solution of the Navier-Stokes equation depending on the body's viscosity with no ad hoc assumptions on its shape and orientation. It reproduces closely the results of Darwinian theories in the case of gaseous planets and stars, but the results are completely different in the case of stiff satellites and planets. It explains the tidal dissipations of Enceladus and Mimas. The extension of the theory to nonhomogeneous icy satellites with a subsurface ocean allows the amplitude of the forced oscillations around synchronization (librations) to be better determined.

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Sylvio Ferraz-Mello, Cristian Beaugé, Hugo Alberto Folonier, Gabriel Oliveira Gomes. 2020-04-02. Tidal friction in satellites and planets. The new version of the creep tide theory. https://doi.org/10.1140/epjst%2Fe2020-900184-5

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