During the Grand Finale orbits, the Cassini spacecraft orbited Saturn with high inclinations and perikrones near the ring plane crossings. The Cosmic Dust Analyzer sampled ice and mineral dust particles during these orbits. In previous work, time-of-flight mass spectra of ring debris close to the ring plane have been analyzed, with the main finding that the detected submicron mineral dust particles consist mostly of Fe-depleted silicates. Here we investigate silicate particles detected at unexpectedly high latitudes of up to 3 Saturnian radii (RS) distance above and below the ring plane. We find striking compositional similarities to those detected close to the main rings, suggesting that these silicates could likewise originate from there. The spatial distribution of lifted main ring material can roughly be constrained to the radial extent of the rings themselves. From there outward water-ice particles become dominant, indicating a vertical E ring extension to 3RS distance to the ring plane here. Using dynamical simulations, we examine conditions under which main ring particles could be ejected to these surprisingly high latitudes. We identify a plausible scenario by assuming ejection velocities of >25 km s–1 and radii <20 nm, allowing for trajectories bent by electromagnetic forces. Such high ejection velocities may be explained if the observed particles form from condensation of a fast vapor phase after micrometeoroid impact onto the rings, a mechanism that has recently been suggested to indeed eject preferably silicate material in the observed size range from the water-ice-dominated rings of Saturn.
