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arXiv · 1901.08561

Rapid falling of an orbiting moon to its parent planet due to tidal-seismic resonance

Yuan Tian·Yingcai Zheng
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Abstract

Tidal force plays an important role in the evolution of the planet-moon system. The tidal force of a moon can excite seismic waves in the planet it is orbiting. A tidal-seismic resonance is expected when a tidal force frequency matches a free-oscillation frequency of the planet. Here we show that when the moon is close to the planet, the tidal-seismic resonance can cause large-amplitude seismic waves, which can change the shape of the planet and in turn exert a negative torque on the moon to cause it to fall rapidly toward the planet. We postulate that the tidal-seismic resonance may be an important mechanism which can accelerate planet accretion process. On the other hand, tidal-seismic resonance effect can also be used to interrogate planet interior by long term tracking of the orbital change of the moon.

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Yuan Tian, Yingcai Zheng. 2019-01-24. Rapid falling of an orbiting moon to its parent planet due to tidal-seismic resonance. https://doi.org/10.1016/j.pss.2019.104796

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