Just how clumpy are Saturn's rings? To answer this question for Saturn's tightly packed B ring (the yellow and inner blue arcs), scientists used a method called occultation. They observed the brightness of a star as it passed behind the rings; this allowed them to calculate areas that are thicker, or clumpier, than others.
In this false color image, the blue areas contain clumps that collide, a finding which surprised scientists. Particles in the yellow area are too densely packed for light to get through.
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