Detail of changes around a probable vent about 650 kilometers north of Prometheus on Jupiter's moon Io as seen in images obtained by the Voyager 1 spacecraft in April 1979 (left) and the imaging system aboard NASA's Galileo spacecraft on September 7th, 1996 (right). The re-arranging of dark and light radial surface patterns may be a result of plume fallout. North is to the top of both images which are approximately 400 kilometers square.

The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).

This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at http://www.jpl.nasa.gov/galileo/sepo.