The presence of the tiny ring moon Daphnis is betrayed by the edge waves
it creates in the Keeler gap.
The gap is a narrow lane, about 42 kilometers (26 miles) wide, in Saturn's
outer A ring. Daphnis (7 kilometers, or 4.3 miles across) was discovered
in Cassini spacecraft images at the same time that scientists spotted the
edge waves. Researchers had suspected the presence of a moon in this gap
after Pan was discovered in Voyager spacecraft images taken 25 years
earlier.
This view looks toward the unilluminated side of the rings from about 54
degrees above the ringplane.
The image was taken in visible light with the Cassini spacecraft
narrow-angle camera on March 17, 2007 at a distance of approximately 1.8
million kilometers (1.1 million miles) from Saturn. Image scale is 10
kilometers (6 miles) 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 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/home/index.cfm. The Cassini imaging team
homepage is at http://ciclops.org.