This image of Tupan Patera, a volcanic crater on Jupiter's moon Io, shows variations of lava interacting with sulfur-rich materials. The rich colors, only slightly enhanced, prove Tupan Patera to be an active volcanic hot spot. The crater, named after a Brazilian thunder god, measures about 47 miles (75 kilometers) across and is surrounded by cliffs about 3,000 feet (900 meters) tall. The black material is warm lava, the yellow is a mix of sulfurous compounds, and the green colors areas where red sulfur has interacted with the dark lava.
NASA / JPL / University of Arizona