Itaca Chasma on Tethys

Caption NASA originale:"Saturn's icy moon Tethys displays a very old impact basin here, just South-East of its giant canyon system, Ithaca Chasma. The large crater has been degraded, or softened, by time and a more recent impact has formed a smaller crater near its southern edge. This large basin was first seen in images from the NASA Voyager mission. A sharper, presumably younger crater called Penelope lies near the eastern limb, at the 3 o'clock position. This view shows principally the trailing hemisphere on Tethys and North is directly up.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on May 20, 2005, at a distance of approx. 1 MKM (approx. 600.000 miles) from Tethys and at a Sun-Tethys-spacecraft, or phase, angle of 31°. Resolution in the original image was 6 Km (about 4 miles) per pixel. The image has been contrast-enhanced and magnified by a factor of two to aid visibility".