Saturn's Rings Linked to Mysterious Atmospheric Hot Spot

Saturn's Lyman-alpha (Lyα) bulge, a bright bar of ultraviolet light, has been explained by a new study that shows how icy particle rain from Saturn's rings heats the planet's upper atmosphere through chemical reactions. The phenomenon has never been observed before in the Solar System and could be used to find other planets with rings similar to Saturn's. The research team studied ultraviolet light readings from several spacecraft and found that icy ring rain is the most likely explanation for the brighter strip of Lyα emission light in the planet's northern hemisphere.