October 8, 2010

Saturn Moons Caught In Paintball Fight

Scientists using data from NASA's Cassini spacecraft have learned that distinctive, colorful bands and splotches embellish the surfaces of Saturn's inner, mid-size moons. The reddish and bluish hues on the icy surfaces of Mimas, Enceladus, Tethys, Dione and Rhea appear to be the aftermath of bombardments large and small.


"The beauty of it all is how the satellites behave as a family, recording similar processes and events on their surfaces, each in its own unique way," Schenk said. "I don't think anyone expected that electrons would leave such obvious fingerprints on planetary surfaces, but we see it on several moons, including Mimas, which was once thought to be rather bland."



"The richness of the Cassini data set "“ visible images, infrared images, ultraviolet images, measurements of the radiation belts "“ is such that we can finally 'paint a picture' as to how the satellites themselves are 'painted,'" said William B. McKinnon, one of six co-authors on the paper. McKinnon is based at Washington University in St. Louis and was also funded by the Cassini data analysis program.







"Analyzing the image color ratios is a great way to really enhance the otherwise subtle color variations and make apparent some of the processes at play in the Saturn system," said Amanda Hendrix, Cassini deputy project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "The Cassini images highlight the importance and potential effects of so-called 'space weathering' that occurs throughout the solar system "“ on any surface that isn't protected by a thick atmosphere or magnetic field."



Image Caption: These three views of Saturn's moon Rhea were made from data obtained by NASA's Cassini spacecraft, enhanced to show colorful splotches and bands on the icy moon's surface. Image credit: NASA/JPL/SSI/LPI