The Nature article “Sodium salts in E-ring ice grains from an ocean below the surface of Enceladus” by F. Postberg et al., discusses the possibility of a liquid subsurface ocean in Saturn’s moon Enceladus. Here follows the abstract. The full paper can be viewed by Nature’s subscribers.
“Saturn’s moon Enceladus emits plumes of water vapour and ice particles from fractures near its south pole, raising the possibility of a subsurface ocean. Minor organic or siliceous components, identified in many ice grains, could be evidence of interaction between Enceladus’ rocky core and liquid water; however it has been unclear whether the water is still present today or if it has frozen. Now, the identification of a population of E-ring grains that are rich in sodium salts suggests that the plumes originate from liquid water.”
Reference: F. Postberg, S. Kempf, J. Schmidt, N. Brilliantov, A. Beinsen, B. Abel, U. Buck & R. Srama, 2009. Sodium salts in E-ring ice grains from an ocean below the surface of Enceladus. Nature 459, 1098-1101. doi:10.1038/nature08046