Melting the core of giant planets: impact on tidal dissipation

TL;DR

This paper investigates how melting of giant planet cores affects tidal dissipation mechanisms, combining planetary interior physics with implications for observed tidal behaviors in Jupiter and Saturn.

Contribution

It provides a novel analysis of how core melting influences viscoelastic and turbulent dissipation processes in giant planets.

Findings

Melting of the core can significantly alter tidal dissipation efficiency.

Core erosion and redistribution impact the internal dynamics of giant planets.

Results suggest modifications to existing models of planetary tidal dissipation.

Abstract

Giant planets are believed to host central dense rocky/icy cores that are key actors in the core-accretion scenario for their formation. In the same time, some of their components are unstable in the temperature and pressure regimes of central regions of giant planets and only ab-initio EOS computations can address the question of the state of matter. In this framework, several works demonstrated that erosion and redistribution of core materials in the envelope must be taken into account. These complex mechanisms thus may deeply modify giant planet interiors for which signatures of strong tidal dissipation have been obtained for Jupiter and Saturn. The best candidates to explain this dissipation are the viscoelastic dissipation in the central dense core and turbulent friction acting on tidal inertial waves in their fluid convective envelope. In this work, we study the consequences of the possible melting of central regions for the efficiency of each of these mechanisms.