Figure 7-19 Jupiter’s Ring and Torus (a) Cutaway diagram of Jupiter’s rings, which are generated from debris blasted off the inner moons Adrastea, Metis, Amalthea, and Thebe. (b) A portion of Jupiter’s faint ring system, photographed by the New Horizons spacecraft heading to Pluto. The outer three bright rings are composed of pebble- to rock-sized fragments. The rest is mostly dust. The brightest portion of the ring is about 6000 km (3700 mi) wide. While the outer edge of the ring is sharply defined, the inner edge is somewhat fuzzy. A tenuous sheet of material extends from the ring’s inner edge all the way down to the planet’s cloud tops. (c) Quarter images of Io’s and Europa’s tori (also called plasma tori because the gas particles in them are charged, that is, the gases are plasmas). Some of Jupiter’s magnetic field lines are also drawn in. Plasma from tori flow inward along these field lines toward Jupiter.