eye_oh.jpgThis image, taken by NASA’s Galileo spacecraft, shows a blue-colored volcanic plume extending about 100 kilometers (about 60 miles) into space from Jupiter’s moon Io. The blue color of the plume is consistent with the presence of sulfur dioxide gas and „snow” condensing from the gas as the plume expands and cools. Galileo images have also shown that the Ra Patera plume glows in the dark, perhaps due to the fluorescence of sulfur and oxygen ions created by the breaking apart of sulfur dioxide molecules by energetic particles in the Jovian magnetosphere.