These raw, unprocessed images of Saturn's moon Hyperion were taken on Aug. 25, 2011, as Cassini conducted its second closest flyby of Hyperion at a distance of about 15,500 miles (25,000 kilometers).
Hyperion is a small moon -- just 168 miles (270 kilometers) across. It has an irregular shape and surface appearance, chaotically rotates, and tumbles along its orbit. Its chaotic rotation prevented scientists from predicting exactly what terrain the spacecraft's cameras would image during this flyby. However, this flyby's closeness has likely allowed Cassini's cameras to map new territory. At the very least, it will help scientists improve color measurements of the moon. It will also allow a determination of how the moon's brightness changes as lighting and viewing conditions change, which can provide insight into the texture of the surface. The color measurements provide additional information about different materials on the moon's deeply pitted surface.
Cassini's closest encounter with Hyperion was on September 26, 2005, when the spacecraft flew approximately 310 miles (500 kilometers) above the moon's surface. Cassini's next flyby of Hyperion will be on Sept. 16, 2011, when it passes the tumbling moon at a distance of about 36,000 miles (58,000 kilometers).