Spectral methods allow the calculation of tidal effects in the interiors of planets and moons

A new spectral method has been developed to compute how tidal forces impact the interiors of planets and moons, offering greater precision for objects with irregular, non-spherical structures. Traditional models often assume a simple spherical shape, but this new method accommodates more complex shapes, which is particularly relevant for bodies with non-uniform compositions or unique surface features.

Body tides—the deformations a celestial body experiences due to gravitational interactions with other objects—cause significant internal heating, especially in bodies with elliptical orbits. For instance, Jupiter’s gravitational pull on Europa leads to strong tidal forces, which heat Europa’s rocky mantle and ice shell, sustaining a subsurface ocean. This tidal energy is crucial to Europa’s habitability, as it could support a liquid water environment that might host simple life forms.

The phenomenon is also observed in Saturn’s moon Enceladus, where non-spherical features in its icy shell contribute to variations in tidal heating. These tidal forces are responsible for creating fissures and sustaining its famous plumes of water vapor, which were detected by the Cassini mission.

The spectral method developed in this study enhances our ability to model these tidal interactions by simulating their effects on planetary bodies with diverse shapes and internal compositions. This approach could improve our understanding of tidal heating processes in other celestial bodies, such as Mercury, Earth’s Moon, and outer solar system objects. It also has implications for interpreting data from future planetary missions that aim to explore these icy worlds in detail.

The study was published in The Planetary Science Journal and is expected to aid researchers in predicting the geological evolution and potential habitability of moons and planets influenced by significant tidal forces.