Скачать или смотреть Callisto's Scars: Asgard Basin

Galileo obtained a 90 meter resolution 12-frame mosaic of the Asgard Basin, extending south from basin center. The video begins at the southern end of this radial mosaic in heavily cratered terrain. Immediately visible in one of the outer concentric rings of this 3000-kilometer wide structure. The outer rings here consist of walled graben or down-dropped troughs, which follow a snake-like path around the center of the basin. Also apparent is the deep erosion that has removed large portions of the graben walls as well as the rims of many craters in this region, leaving a dark surface residue. Despite the erosion, these graben remain at least 1 kilometer deep. As we fly forward we see more craters and additional graben rings. If you look closely you can see small landslide deposits on the floors of some craters. As we fly further north we begin to transition to the inner ring zone, which have the form of ridges rather than graben fractures. Further north, the terrain brightens and is less cratered. This is in fact the outer zone of a large 115-kilometer wide crater Doh, which formed some time after Asgard. At the center of Doh is a 25-kilometer-wide central dome. The surface of the dome is densely fractured, suggesting that it expanded upward as it cooled, cracking the surface. Formation of Doh obscures any features that might have existed at the center of Asgard. No stereo imaging was obtained with this mosaic, all topographic data are based on shape-from-shading techniques.

All mosaic, topographic and video products were produced at the Lunar and Planetary Institute by Dr. Paul Schenk, 2009. Visit me at: http://stereomoons.blogspot.com