For an Earth observer on May 3, 2005, the Cassini spacecraft appeared to
pass behind the rings, then Saturn, then the rings again (the red line).
The discovered harmonic structure was found on both the way in and out,
but only in locations where particles are densely packed together, such as
the B ring and the innermost part of the A ring.
The May 3 radio experiment and several others to follow in 2005 showed
that the regular spacing of the harmonic structure vary from 100 to 250
meters (320 to 820 feet), depending on the location in the rings. To see
an illustration of this occultation see PIA10232.
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.
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.
