Slope failure near Aratus crater

Northern flank of cone-shaped mound near Aratus crater. LROC NAC M117461002L, image width is about 672 m. Sun light is from left side, incidence angle 83°, downslope direction is from bottom to top of the image [NASA/GSFC/Arizona State University].

The image displays a mixture of smooth (denoted as "S"), bumpy (B), and rough textured (R) surfaces. Some of the bumpy textured material is enclosed by the rough textured material. The downhill-side edges of the smooth areas are scalloped and are often accompanied by parallel wrinkles. The uphill edges of each piece of smooth-textured surface appear to have separated from the smooth material up-slope from them, leaving a gap of rough surfaced material. It is possible that these characteristics indicate slope failure (landslide) of an upper thin layer, similar to what we see on terrestrial landslides or a snow avalanche. This type of sliding occurs where the material strengths of upper and subsurface layers have large contrast, typically unconsolidated material overlaying a more rigid substrate.

Estimates of sliding layer thickness, local topography, and morphologic characterization of flow features allow scientists to determine the geotechnical (soil mechanics) properties of the regolith. Such studies are key to designing future rovers, space suits, and tools for exploring the Moon.

Context map for Aratus crater. Image center location is 4.43°E, 23.09°N. LROC WAC 100 m/pix monochrome global mosaic overlayed with WAC color DTM 500 m/pixel. Blue dashed box corresponds to the footprint of today's featured NAC image [NASA/GSFC/Arizona State University].

Explore lunar landslides by viewing the full NAC frame!

Published by Hiroyuki Sato on 16 November 2010