Images taken by NASA's Galileo spacecraft with different angles of sunlight help scientists interpret the three- dimensional shape of structures on Jupiter's moons. This pair shows a mountain named Tohil Mons on the innermost of Jupiter's four large moons, Io. The top image was taken at low resolution and a low Sun angle during Galileo's third orbit, in 1996. Because the Sun is low, topographic features on the mountain can be recognized from the shadows they cast. Labels indicate the peak of the mountain and two volcanic depressions, called paterae. The bottom image was taken on Feb. 22, 2000, at higher resolution and a higher Sun angle. The smallest visible features are about 165 meters (540 feet) across. The topography is almost indistinguishable, but many more details can be discerned. By combining several observations in this manner, Galileo scientists are able to study Io's mountains and to learn about their evolution and their relationship to Io's volcanoes. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Galileo mission for NASA's Office of Space Science, Washington, D.C. Images and data received from Galileo are posted on the Galileo mission home page at http://www.jpl.nasa Background information and educational context for the images can be found at http://www.jpl.nasa . # # # # #
Description
Images taken by NASA's Galileo spacecraft with different angles of sunlight help scientists interpret the three- dimensional shape of structures on Jupiter's moons. This pair shows a mountain named Tohil Mons on the innermost of Jupiter's four large moons, Io. The top image was taken at low resolution and a low Sun angle during Galileo's third orbit, in 1996. Because the Sun is low, topographic features on the mountain can be recognized from the shadows they cast. Labels indicate the peak of the mountain and two volcanic depressions, called paterae. The bottom image was taken on Feb. 22, 2000, at higher resolution and a higher Sun angle. The smallest visible features are about 165 meters (540 feet) across. The topography is almost indistinguishable, but many more details can be discerned. By combining several observations in this manner, Galileo scientists are able to study Io's mountains and to learn about their evolution and their relationship to Io's volcanoes. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Galileo mission for NASA's Office of Space Science, Washington, D.C. Images and data received from Galileo are posted on the Galileo mission home page at http://www.jpl.nasa Background information and educational context for the images can be found at http://www.jpl.nasa . # # # # #