Evidence of hydrothermal activity on Enceladus

Hsiang-Wen Hsu et al. have analysed the silicon-rich, nanometre-sized dust stream particles in the Saturnian system using the Cosmic Dust Analyser (CDA) onboard the Cassini spacecraft. With the help of experiments and modelling, the particles are interpreted as silica grains that were initially embedded in the icy plume emitted from subsurface waters on Enceladus and released by sputter erosion in Saturn’s E ring. Their properties indicate their formation and transport by high-temperature hydrothermal reactions from the ocean floor and up into the plume of Enceladus.