The images used to create this color composite of Io were acquired by Galileo
during its ninth orbit (C9) of Jupiter and are part of a sequence of images
designed to map the topography or relief on Io and to monitor changes in the
surface color due to volcanic activity. Obtaining images at low illumination angles
is like taking a picture from a high altitude around sunrise or sunset. Such lighting
conditions emphasize the topography of the volcanic satellite. Several mountains
up to a few miles high can be seen in this view, especially near the upper right.
Some of these mountains appear to be tilted crustal blocks. Most of the dark
spots correspond to active volcanic centers.

North is to the top of the picture which merges images obtained with the clear,
red, green, and violet filters of the solid state imaging (CCD) system on NASA's
Galileo spacecraft. The resolution is 8.3 kilometers per picture element. The
image was taken on June 27, 1997 at a range of 817,000 kilometers by the solid
state imaging (CCD) system on NASA's Galileo spacecraft.

Launched in October 1989, Galileo entered orbit around Jupiter on December 7,
1995. The spacecraft's mission is to conduct detailed studies of the giant planet,
its largest moons and the Jovian magnetic environment. The Jet Propulsion
Laboratory, Pasadena, CA manages the mission for NASA's Office of Space
Science, Washington, DC.

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://www.jpl.nasa.gov/galileo.