PIA01058: Bright and Dark Slopes on Ganymede

Bright and Dark Slopes on Ganymede


Ridges on the edge of Ganymede's north polar cap show bright east-facing slopes and dark west-facing slopes with troughs of darker material below the larger ridges. North is to the top. The bright slopes may be due to grain size differences, differences in composition between the original surface and the underlying material, frost deposition, or illumination effects. The large 2.4 kilometer (1.5 mile) diameter crater in this image shows frost deposits located on the north-facing rim slope, away from the sun. A smaller 675 meter (2200 foot) diameter crater in the center of the image is surrounded by a bright deposit which may be ejecta from the impact. Ejecta deposits such as this are uncommon for small craters on Ganymede. This image measures 18 by 19 kilometers (11 by 12 miles) and has a resolution of 45 meters (148 feet) per pixel. NASA's Galileo spacecraft obtained this image on September 6, 1996 during its second orbit around Jupiter.

Background Info:

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 .

Cataloging Keywords:

Name Value Additional Values
Target Ganymede Jupiter, Sun
System Jupiter
Target Type Satellite Planet, Sun
Mission Galileo
Instrument Host Galileo Orbiter
Host Type Orbiter
Instrument Solid-State Imaging (SSI)
Extra Keywords Crater, Grayscale
Acquisition Date
Release Date 1997-11-18
Date in Caption 1996-09-06
Image Credit NASA/JPL/Brown University
Source photojournal.jpl.nasa.gov/catalog/PIA01058
Identifier PIA01058