Giant "Propeller" in the A-Ring (CTX Frame)

An unusually large "Propeller" feature is detected just beyond the Encke Gap in this Cassini image of Saturn’s outer A-Ring taken a couple days after the Planet’s August 2009 Equinox.

The unique geometry of Equinox has thrown into relief small moonlets within the Rings and the structures they create around them. Propeller-like features, a few kilometers long, centered on and created by the action of small embedded moonlets only about 100 meters across, were discovered early in the mission (see also PIA07792 and PIA07790).
These previous findings constituted the first recognition of the presence in Saturn’s Rings of bodies bigger than the largest ring particles (about 10 meters, or 30 feet, across) but smaller than the 8-Km-wide (about 5-mile-wide) ring moon, Daphnis, in the outer A-Ring.

From the 350-Km (about 220-mile) length of the shadow cast by this 130-Km-long (about 80-mile-long) Propeller, the heights of these features above the Ring-Plane have been measured to reach about 200 meters (650 feet), indicating the moonlet responsible for the Propeller in this image is likely to be 400 meters (1300 feet) across.

A previously released early-Equinox image also had revealed a moonlet in the outer B-Ring about 400 meters (1300 feet) across (see PIA11665).