This Galileo SSI view of Ganymede's Marius Regio and Nippur Sulcus regions shows the dark and bright grooved terrain typical of this satellite. This regional scale view was imaged near the terminator (the line between day and night). The older, more heavily cratered dark terrain of Marius Regio is rutted with furrows, shallow troughs perhaps formed as a result of ancient giant impacts. Bright grooved terrain is younger and is formed through tectonism probably combined with icy volcanism.
North is to the top left of the picture and the sun illuminates the surface from the lower right. The images in this mosaic were taken on May 7, 1997 at a resolution of 940 meters per pixel. The mosaic was created by unmannedspaceflight.com user OWW.