3 septiembre 2015
When the sun set on Saturn’s rings in August 2009, scientists on NASA’s Cassini mission were watching closely. It was the equinox — one of two times in the Saturnian year when the sun illuminates the planet’s enormous ring system edge-on. The event provided an extraordinary opportunity for the orbiting Cassini spacecraft to observe short-lived changes in the rings that reveal details about their nature.
http://www.sciencedaily.com/releases/2015/09/150903120738.htm
