This is a Hubble Space Telescope of the November 1995 nearly edge-on view of Saturn's rings.
Before the Voyager 2 spacecraft flew by Saturn, astronomers had deduced that, because Saturn's rings disappeared when seen edge on, that the ring system must be less than 35 kilometers thick. By watching the change in brightness of the ring system over the 29 year orbital period around the Sun, they deduced that the ring particles were twice as reflective as Saturn itself. By bouncing radar pulses off of the rings, a major technological feat, they concluded that the ring particles were not much more than one meter across. Studies of the absorption of light from distant stars eclipsed by the rings were able to detect absorption by ice, so from all of this we deduced that the rings were ice-coated, very reflective small bodies that orbited Saturn by the 100's of billions.
Voyager 2 flew by the rings and showed them to be not 8 - 10 entities, but thousands of individual ringlets. Some rings were only a few kilometers wide. The thickness of the ring plane was now deduced to be less than 100 meters! If you collapsed all of the vertical spaces between the ring particles, they would form a disk only 1 - 2 meters thick, but extending over 300,000 kilometers around Saturn, making them the thinnest objects in the solar system.
The detailed structure of the ring system is complex and includes many factors such as the presence of the 'ring moons' that shepard the rings and keep them organized, and resonances between ring particles and the other satellites that cause large gaps in the rings.
Copyright 1997 Dr. Sten Odenwald
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