The Cassini spacecraft survived the flyby, actually a fly-through of the ice-water plumes shooting out from the surface of Saturn’s moon, Enceladus. This is quite an accomplishment considering the fact that the speed of the water vapor particles in the plume were gushing up from the surface at 400 meters per second, or 800 mph.
Additionally, Cassini was speeding by at 15 km per second or 32,000 mph. Cassini picked up for analysis samples of the ice/water mixture shooting up from the surface of Enceladus.
Two instruments collecting data for analysis are the Cosmic Dust Analyzer and the Ion & Neutral Mass Spectrometer. The analysis will be looking for evidence of an Earth-like ocean of water and/or organic compounds inside the tiny moon that are not visible telescopically.
Specifically, Cassini’s particle analyzers dissected the “body” of the plume searching for information on the density, size, composition and velocity of the particles within it. The data should help determine whether the gasses in the plume match the halo of particles around Enceladus.
These geysers may originate from this ocean beneath the surface, spewing out from fractures along the south pole of Enceladus. The working assumption has been that water is trapped under the iced over crust of the moon. This flyby will provide a detailed view of these fractures and will enable a better comparison of geological history of the north and south poles.
New images show the north pole to be older as evidenced by the many craters in the north compared to the rarity of these in the south. These craters in the north have small parallel slices running through them, possibly from heating and cooling cycles and perhaps tectonic activity.
Cassini first discovered these geyser like jets in 2005, finding that the continuous eruption of the water vapor plumes create a gigantic halo of ice dust and gas around Enceladus. Much of this material is eventually drawn into Saturn’s E-ring due to its proximity to Enceladus.
Another flyby will occur in August and another in October of this year. Cassini’s mission was scheduled to end this June, however, it has been extended. Cassini will make up to seven more flybys of Enceladus. Recent news and more pictures regarding Cassini’s mission can be found at the NASA web site for Cassini here.