Jupiter's moon of Io was the first other planet or moon in the universe to be shown exhibiting volcanic activity other than Earth. The picture was taken by the Galileo spacecraft. The activity, called the Prometheus Plume, has been active every time a flyby of Io has been done, including the Voyager flyby some 18 years prior, making it likely that the plume has been continuously active for over twenty years. The image has been digitally sharpened, and was taken at the distance of 600,000 miles