Enceladus' "Tiger Stripes"

Da "NASA - Picture of the Day" del 6 Settembre 2005:"The Tiger Stripes on Saturn's moon Enceladus might be active. Even today, they may be spewing ice from the Moon's icy interior into space, creating a cloud of fine ice particles over the Moon's South Pole and creating Saturn's mysterious E-Ring. Recent evidence for this has come from the Cassini spacecraft. Cassini detected a marked increase in particle collisions during its July flyby only 270 Km over a South Polar Region of Enceladus. Pictured above, a HR image of Enceladus is shown from the close flyby. The unusual surface features dubbed "Tiger Stripes" are visible on the left in false-color blue. Why Enceladus is active remains a mystery, as the neighboring moon Mimas, approximately the same size, appears quite dead".