The first high-resolution images of the bright side of Saturn's two-toned moon Iapetus, shown here in a false-color mosaic, reveal a pair of overlapping impact craters and a dark fuzz of presumed hydrocarbons and other compounds (green) pooled on crater floors and equator-facing slopes. The Cassini spacecraft captured the images with its narrow-angle camera on a September 10, 2007, flyby from a distance of about 45,000 miles (73,000 kilometers). NASA said the images should help decipher the origin of the moon's twin tones.