19 October 2004
The fretted terrains of Mars were described briefly earlier this month in "Craters in Fretted Terrain." Today's Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) Picture of the Day shows another example of a fretted terrain valley floor with its characteristic lineated and finely-pitted texture. Four circular features near the center/left center of the image are suspected to be the locations of meteor impact craters that have been largely eroded away. Mars is a complex world upon which have acted processes of erosion that are not fully understood. This image is located near 40.4°N, 336.2°W. The image covers an area about 3 km (1.9 mi) wide and sunlight illuminates the scene from the lower left.