Io Coloured Galileo spacecraft image of Io the innermost of Jupiters Galilean moons Dark areas correspond to volcanic hot spots may be active lava flows The red orange yellow colours come from various forms and compounds of sulphur which cover most of the surface The white areas are probably sulphur dioxide frost The intense volcanic activity has resulted in mountains layered plateaus and depressions The side of Io seen here permanently faces away from Jupiter This image was made by combining highresolution data taken by Galileos Solid State Imaging CCD instrument on November with lowresolution colour images acquired on September