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Stereo Topography Reveals Geological Processes on Outer Planet Moons

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 the USRA 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.

During the vehicle's first ten years exploring the Saturn system, NASA's Cassini spacecraft took images making up a mosaic of Saturn's moon Enceladus. USRA's Paul Schenk created maps using data from Cassini which shine a new light on Saturn's six major icy moons: Mimas, Enceladus, Tethys, Dione, Rhea and Iapetus. Results were featured by as "Best-Ever Maps of Saturn's Icy Moons."

mosaic of Saturn's moon Enceladus

Image Credit: NASA/JPL-Caltech/Space Science Institute/USRA Lunar and Planetary Institute.

Cassini will continue to study Saturn and its moons until September 2017, when the probe will intentionally dive into the planet's thick atmosphere.