Saturn's ring-embedded moons, Pan and Daphnis, are captured in a single
Cassini spacecraft narrow-angle frame in an alignment they repeat with the
regularity of a precise cosmic clock. Pan is closer to Saturn, and thus
orbits faster, and Pan overtakes Daphnis every 19 days.
The flying-saucer-like shape of Pan (26 kilometers, or 16 miles across)
can easily be discerned here. Daphnis (7 kilometers, or 4.3 miles across)
is a mere speck, although its presence is made obvious by the edge waves
it creates in the surrounding ring material.
Pan also raises waves in the edges of the Encke Gap (see PIA06099). However,
even though Pan is more massive than Daphnis, Pan is farther from the
edges of its gap than the smaller moon. This causes Pan's edge waves to
have a much longer wavelength (they are more stretched out) and a smaller
amplitude (they do not extend as far inward from the gap edge) as those
created by Daphnis, making them more difficult to see.
This view looks toward the sunlit side of the rings from about 24 degrees
below the ringplane.
The image was taken in visible light with the Cassini spacecraft
narrow-angle camera on March 24, 2007 at a distance of approximately
889,000 kilometers (553,000 miles) from Daphnis and at a
Sun-Daphnis-spacecraft, or phase, angle of 21 degrees. Image scale is 5
kilometers (3 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.