Particles in Saturnís rings

Particles in Saturnís rings

Fig. 10.11 . When the Cassini spacecraft passed behind the rings of Saturn, it sent three simultaneous radio signals, at 0.94, 3.6 and 13 centimeter wavelength, through the rings to Earth. The observed changes of each signal as the spacecraft moved behind the rings provided a profile of the distribution of ring material as a function of distance from Saturn, or an optical depth profile. The image shown here was constructed from these profiles, depicting the observed ring structure at about 10 kilometers in resolution. Color is used to present information about the presence or absences of small ring particles in different regions based on the measured effects of the three radio signals. Purple color indicates regions where there is a lack of particles of size less than 5 centimeters. Green and blue shades indicate regions where there are particles smaller than 5 centimeters and 1 centimeter, respectively. The saturated broad white band is the densest region of the B ring, which blocked two of the three radio signals. From other evidence in the radio observations, all ring regions appear to be populated by a broad range of particle sizes that extend to several meters across. (Courtesy of NASA/JPL.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University