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Recent studies of stellar occultations observed by the Visual and InfraredMapping Spectrometer (VIMS) onboard the Cassini spacecraft have demonstratedthat multiple spiral wave structures in Saturn's rings are probably generatedby normal-mode oscillations inside the planet. Wavelet-based analyses have beenable to unambiguously determine both the number of spiral arms and the rotationrate of many of these patterns. However, there are many more planetary normalmodes that should have resonances in the rings, implying that many normal modesdo not have sufficiently large amplitudes to generate obvious ring waves.Fortunately, recent advances in wavelet analysis allow weaker wave signals tobe uncovered by combining data from multiple occultations. These new analyticaltools reveal that a pattern previously identified as a single spiral waveactually consists of two superimposed waves, one with 5 spiral arms rotating at1593.6 degrees/day and one with 11 spiral arms rotating at 1450.5 degrees/day.Furthermore, a broad search for new waves revealed four previously unknown wavepatterns with 6, 7, 8 and 9 spiral arms rotating around the planet at 1538.2degrees/day, 1492.5 degrees/day, 1454.2 degrees/day and 1421.8 degrees/day,respectively. These six patterns provide precise frequencies for another sixfundamental normal modes inside Saturn, yielding what is now a completesequence of fundamental sectoral normal modes with azimuthal wavenumbers from 2to 10. These frequencies should place strong constraints on Saturn's interiorstructure and rotation rate, while the relative amplitudes of these wavesshould help clarify how the corresponding normal modes are excited inside theplanet.

Kronoseismology IV. Six previously unidentified waves in Saturn's middle C ring