Theoretical free oscillations spectrum for Saturn interior models Original Research Article

The theoretical spectrum of free oscillations of Saturn is considered for a set of new interior structure models. Planetary acoustic mode frequencies are calculated for radial order up to 20 and degree up to 15. The diagnostic capabilities of the discontinuity gravitational modes related to the density jumps in the molecular envelope of Saturn and at the interface between its molecular and metallic envelopes are of particular interest. These two modes have non-zero displacement at the planetary surface and their periods could resonate with the orbital periods of D- and C-ring particles. The results of numerical experiments emphasize the relevancy not only of determining the periods from observations but also studying the excitation mechanisms in order to deal with the expected amplitudes of the eigenmodes.