The Cassini spacecraft now orbiting Saturn is providing unprecedented information about Saturn and its icy moons. Enceladus, one of Saturn's many moons, is of particular interest: from a sub-surface reservoir of briny water beneath its south pole, massive plumes of ice and gas are erupting into space. This vented material, which coats the surfaces of Enceladus and other Saturnian satellites, provides clues to temperatures and compositions inside Enceladus. Stereo topographic images and elevations provide scientists at USRA's Lunar and Planetary Institute with clues and constraints on geological processes and activities inside the Saturnian satellites, such as just how long the plumes have been active (tens of millions of years, as opposed to the original estimate of hundreds of years). Additionally, they provide insight as to how the snow deposits change the appearance and properties of Enceladus itself - where images used to show sharp edges of canyon rims, now there appear smooth, rounded surfaces due to the snow.
Perspective view of heavily fractured, cratered terrain on Enceladus, using images from the Cassini spacecraft. The view is ~ 5 km across and shows hill and rifts coated with snow from Enceladus' plumes of ice and vapor. This image was developed by Dr. Paul Schenk of USRA's Lunar Planetary Institute.