Click for larger annotated version
Radio signals sent by NASA's Cassini spacecraft to Earth through Saturn's
rings revealed the presence of highly unusual regular formations of
densely grouped ring particles. The harmonic ring structure caused the
radio signal frequency to separate into three distinct components. The
observed frequencies determine the regular spacing to be as small as 100
meters (320 feet), the finest-scale ring structure observed so far.
The regularly spaced yellow grid depicts the harmonic structure in
Saturn's inner Ring A, and the image on the bottom right shows an actual
observed frequency pattern (spectrogram). Color represents the observed
signal strength. The structure acts like an enormously extended natural
diffraction grating that separates the signal frequency into the three
distinct components shown. The frequencies determine the regular spacing
of the diffraction grating, 160 meters (500 feet) in this case. The image
of Saturn was taken with Cassini's cameras and is shown here to illustrate
the occultation. For additional information on the radio observations see
PIA10233.
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. The radio
science team is based 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. For more information on the radio
science team visit http://saturn.jpl.nasa.gov/spacecraft/instruments-cassini-rss.cfm.
The Cassini imaging team homepage is at http://ciclops.org.