This set of Cassini spacecraft images shows a close-up view of two
propeller structures in Saturn's A ring. These images are part of a large
view (see PIA10079) that captures eight new propeller-like features in
what may be the propeller "hot zone" of Saturn's rings.
Propellers were first discovered in Cassini images taken during Saturn
orbit insertion in 2004. Propellers form around small moonlets that are
not massive enough to clear out ring material, but are still able to push
the ring particles into a shape reminiscent of an airplane propeller.
These pictures show two new propellers close up (one centered on each
image). These images were put together from images in the Planetary Data
System, a web site which archives and distributes scientific data from
NASA planetary missions. The image on the top shows a propeller induced
by a 150-meter (490-foot) moonlet (See PIA10079 for a global view; with
this close up marked with a red box). Smaller bright spots in the image
are artifacts. The image on the bottom shows another propeller located
just outside of the Encke Gap. Fine horizontal stripes seen in the image
are wakes induced by the moon Pan.
In the top clear-filter image, taken during a stellar occultation on Aug.
20, 2005, the Cassini spacecraft narrow-angle camera observed the unlit
side of the rings, with a phase angle of 126 degrees. The images were
taken at 1 minute intervals with 0.05 seconds exposure time. Image
resolution is 1 kilometer (0.6 miles) per pixel. The bottom clear-filter
image was taken few hours later with 2 seconds exposure time. Image
resolution is 1.5 kilometer (1 mile) per pixel.
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 was designed, developed and assembled at JPL.
For more information about the Cassini-Huygens mission visit
http://saturn.jpl.nasa.gov/home/index.cfm.
