The Cassini probe, launched in 1997, began orbiting Saturn in 2004. Cassini was designed to study Saturn, its rings, and its moons and to drop a probe called Huygens into the atmosphere of the moon Titan. The observed change of each signal as Cassini 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. (Image Credit: NASA/JPL)
Unraveling Saturn Rings
In this simulated image of Saturn’s rings, color is used to represent information about ring particle sizes in different regions based on the measured effects of three radio signals. Three simultaneous radio signals of 0.94, 3.6 and 13 centimeter wavelength (Ka-, X- and S-bands) were sent from the Cassini spacecraft through the rings to Earth.