Icy Tectonics

Explanation: NASA's Cassini spacecraft captured this mosaic of Saturn's icy and geologically active moon Enceladus on Oct. 5, 2008, just after coming within 25 kilometers (15.6 miles) of its surface. Enceladus' surface is replete with fractures, folds, and ridges - all hallmarks of remarkable tectonic activity for a relatively small world.

Pluto

Image credit: NASA/JPL/Space Science Institute.