Topic summary
F Ring
Extracted from the Wikipedia article Rings of Saturn.
F Ring
The F Ring is the outermost discrete ring of Saturn and perhaps the most active ring in the Solar System, with features changing on a timescale of hours. It is located 3,000 km (2000 miles) beyond the outer edge of the A ring. The ring was discovered in 1979 by the Pioneer 11 imaging team. It is very thin, just a few hundred km in radial extent. While the traditional view has been that it is held together by two shepherd moons, Prometheus and Pandora, which orbit inside and outside it, recent studies indicate that only Prometheus contributes to the confinement. Numerical simulations suggest the ring was formed when Prometheus and Pandora collided with each other and were partially disrupted.