Evidence for temporal variability of Enceladus' gas jets: Modeling of Cassini observations

Time variability of Enceladus' gas plume is deduced from a joint investigation of Cassini spacecraft magnetic field data obtained during the first three flybys E0, E1 and E2 and neutral density measurements during the E2 flyby with a model that describes Enceladus' plasma interaction with individual jets. We infer a total plume content of similar to 7 x 10(32) H(2)O molecules corresponding to a mass loss rate of similar to 1600 kg/s for the E0 flyby and similar to 9 x 10(31) H(2)O molecules corresponding to a mass loss of similar to 200 kg/s for the E1 and E2 flybys. The magnetic field measurements also support upstream/downstream changes of the plume activity locations. On the first three Enceladus flybys Cassini did not fly through the densest parts of the plumes, which were a factor of 10-100 times higher at the same altitudes. Citation: Saur, J., N. Schilling, F. M. Neubauer, D. F. Strobel, S. Simon, M. K. Dougherty, and C. T. Russell (2008), Evidence for temporal variability of Enceladus' gas jets: Modeling of Cassini observations, Geophys. Res. Lett., 35, L20105, doi: 10.1029/2008GL035811.