Cassini Finds Massive Jupiter Gas Cloud

Stretching millions of miles around Jupiter, the donut- shaped cloud, known as a "torus," is believed to result from the uncommonly severe bombardment of ion radiation the jovian giant sends toward Europa. That radiation damages Europa's surface, kicking up and pulling apart water-ice molecules and dispersing them along the moon's orbit into a neutral-gas torus with a mass of about 60,000 tons.