A close-up of Saturn's A ring reveals dozens of small, bright streaks
aligned with the orbital direction of the rings. These objects are the
propeller-shaped features first captured in Cassini images during the
spacecraft's 2004 orbital insertion maneuver, as Cassini skimmed just
above the ringplane.
The propeller features were announced in 2006 (see PIA07792).
Each propeller is the visible gravitational disturbance created around a
small moonlet embedded in the ring. The moonlets are likely between 10 and
100 meters (30 to 300 feet) across. Cassini imaging scientists have
previously found that propeller swarms like this occur primarily in three
narrow bands in the middle part of the A ring.
This view looks toward the sunlit side of the rings from about 35 degrees
below the ringplane. The image was taken in visible light with the Cassini
spacecraft narrow-angle camera on Sept. 25, 2008. The view was acquired at
a distance of approximately 219,000 kilometers (136,000 miles) above the
rings and at a Sun-ring-spacecraft, or phase, angle of 127 degrees. Image
scale is 1 kilometer (0.6 mile) per pixel in the radial, or outward from
Saturn direction and 2 kilometers (1 mile) in the longitudinal, or around
Saturn, direction.
The Cassini-Huygens mission is a cooperative project of NASA, the European
Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory,
a division of the California Institute of Technology in Pasadena, manages
the mission for NASA's Science Mission Directorate, Washington, D.C. The
Cassini orbiter and its two onboard cameras were designed, developed and
assembled at JPL. The imaging operations center is based at the Space
Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit
http://saturn.jpl.nasa.gov/. The Cassini imaging team
homepage is at http://ciclops.org.
