Galileo images of the surface of Jupiter's moon Callisto have revealed large landslide deposits within two large impact craters seen in the right side of this image. The two landslides are about 3 to 3.5 km in length. They occurred when material from the crater wall failed under the influence of gravity, perhaps aided by seismic disturbances from nearby impacts. These deposits are interesting because they traveled several kilometers from the crater wall in the absence of an atmosphere or other fluids that might have lubricated the flow. This could indicate that the surface material on Callisto is very fine-grained, and perhaps is being "fluffed" by electrostatic forces that allowed the landslide debris to flow extended distances in the absence of an atmosphere.
Date: 10 Dec 1997
This image was acquired on September 16, 1997, by the Solid-State Imaging System onboard the Galileo spacecraft during it's tenth orbit around Jupiter. North is to the top of the image, with the Sun illuminating the scene from the right. The center of this image is located near 25.30N latitude, 141.30W longitude. The image, which is 55 kilometers by 44 kilometers across, was acquired at a resolution of 100 meters per picture element.
Image Credit: Arizona State University
Credit: Lunar and Planetary Institute