http://spaceref.com/saturn/enceladus-pl ... atory.html
"Except for measurements in Earth's upper atmosphere, there have previously been no in-situ observations of dusty plasma in space."
They found a high plasma density (both ions and electrons) within the Enceladus plume region, although the electron densities are usually much lower than the ion densities in the plumes and in the E ring.
In a dusty plasma, conditions are just right for the dust to also participate in the plasma's collective behavior. This increases the complexity of the plasma, changes its properties and produces totally new collective behavior. Dusty plasma are thought to exist in comet tails and dust rings around the sun, but scientists rarely have the opportunity to fly through the dusty plasma and directly measure its characteristics in place.
"The Cassini plasma spectrometer has enabled us to discover and analyze new classes of charged particles that were wholly unanticipated when the instrument was designed and built in the 1980s and 90s," said Tom Hill,