The atmosphere of Jupiter is colorful, with cloud bands of alternating colors. A major characteristic of the atmosphere is the appearance of regularly spaced features. Around the northern edge of the equator, a train of plumes is observed, which has bright centers representative of cumulus convection similar to that seen on Earth. At both northern and southern latitudes, cloud spots are observed spaced almost all the way around the planet, suggestive of wave interactions. The cloud structures in the northern and southern hemispheres are distinctly different. However, the velocities between the bright zones and dark belts appear to be symmetric about the equator, and stable over many decades. This suggests that such long-lived and stable features may be controlled by the atmosphere far beneath the visible clouds. The Great Red Spot possesses the same meteorological properties of internal structure and counterclockwise rotation as the smaller white spots. The color of the Great Red Spot may indicate that it extends deep into the Jovian atmosphere. Cloud-top lightning bolts, similar to those on Earth, have also been found in the Jovian atmosphere. At the polar regions, auroras have been observed. A very thin ring of material less than one kilometer (0.6 mile) in thickness and about 6000 kilometers (4000 miles) in radial extent has been observed circling the planet about 55,000 kilometers (35,000 miles) above the cloud tops. Amalthea Amalthea is an elongated, irregularly shaped satellite of reddish color. It is 265 kilometers (165 miles) long and 150 kilometers (90 miles) wide. Just like the large Galilean satellites, Amalthea is in synchronous rotation, with its long axis always oriented toward Jupiter. At least one significant color variation has been detected on its surface. Io Eight active volcanoes have been detected on Io, with some plumes extending up to 320 kilometers (200 miles) above the surface. Over the four-month interval between the Voyager 1 and 2 encounters, the active volcanism appears to have continued. Seven of the volcanoes were photographed by Voyager 2, and six were still erupting. The relative smoothness of Io’s surface and its volcanic activity suggest that it has the youngest surface of Jupiter’s moons. Its surface is composed of large amounts of sulfur and sulfur dioxide frost, which account for the primarily yellow-orange surface color. The volcanoes seem to eject a sufficient amount of sulfur dioxide to form a doughnut-shaped ring (torus) of ionized sulfur and oxygen atoms around Jupiter near Io’s orbit. The Jovian magnetic field lines that go through the torus allow particles to precipitate into the polar regions of Jupiter, resulting in intense ultraviolet and visible auroras. Europa