No pseudosynchronous rotation for terrestrial planets and moons

Valeri V. Makarov; Michael Efroimsky

doi:10.1088/0004-637x/764/1/27

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arXiv · 1209.1616

No pseudosynchronous rotation for terrestrial planets and moons

Valeri V. Makarov·Michael Efroimsky

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Abstract

We reexamine the popular belief that a telluric planet or satellite on an eccentric orbit can, outside a spin-orbit resonance, be captured in a quasi-static tidal equilibrium called pseudosynchronous rotation. The existence of such configurations was deduced from oversimplified tidal models assuming either a constant tidal torque or a torque linear in the tidal frequency. A more accurate treatment requires that the torque be decomposed into the Darwin-Kaula series over the tidal modes, and that this decomposition be combined with a realistic choice of rheological properties of the mantle. This development demonstrates that there exist no stable equilibrium states for solid planets and moons, other than spin-orbit resonances.

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Valeri V. Makarov, Michael Efroimsky. 2012-09-07. No pseudosynchronous rotation for terrestrial planets and moons. https://doi.org/10.1088/0004-637x/764/1/27

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