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

## TL;DR

This paper investigates how tidal-seismic resonance can cause a moon to rapidly fall into its parent planet by amplifying seismic waves, affecting planetary shape and orbital dynamics, with implications for planet formation and interior analysis.

## Contribution

It introduces the concept that tidal-seismic resonance can significantly accelerate moon infall and offers a new method to study planetary interiors through orbital tracking.

## Key findings

- Tidal-seismic resonance can induce large seismic waves in the planet.
- Resonance can cause the moon's orbit to decay rapidly.
- Potential application in probing planetary interior structures.

## 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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Source: https://tomesphere.com/paper/1901.08561