
Little Tethys is getting a lot of face time in front of Cassini’s lens.
In this photo, from a raw image taken on October 17, Tethys passes across the hazy face of her much larger sister, Titan. 662-mile-wide Tethys is dwarfed by the 3,200-mile-wide Titan, although the distance that separates them in this image reduces the apparent size difference.
The 1200-mile-long scar of the Ithaca Chasma can be seen running down the illuminated side of Tethys. A system of 3-mile-deep canyons, the Chasma extends from the moon’s north pole nearly all the way to its south, possibly caused by the expansion of internal water ice.

Image: NASA/JPL/SSI
Update: I just had to do it. Click the preview at right for an animation of the two moons passing. 🙂
AND: Click here for a colorized version of the top image by the amazingly skillful Gordan Ugarkovic.