The unique morphology of craters such as this one (-17.25°S, 350.46°E) is the result of a contrast in the strength of a surface layer (in this case, the unconsolidated regolith) and a stronger underlying layer (here, mare basalt). The relatively weak regolith is more easily excavated than the basalt, resulting in the distinct "inner ring". For a given thickness of regolith (typically meters thick), craters formed entirely within the regolith are bowl-shaped. At increasing diameters, the crater excavates below the regolith into the stronger basalt flows, and they exhibit a central mound, a flat floor, and finally a concentric ring inside the crater rim.
Immediately inside the rim is a ridge with a diameter of about 167 m; the ridge itself is about 50-70 m wide and stands about 20 m above the adjacent crater floor. The center of the crater is marked by a low-reflectance rough area about 36 m in diameter, surrounded by a subtle ridge.
Scattered across the inner ridge and crater rim and extending beyond the crater rim is bright, bouldery ejecta. Boulders as large as 11 m have been ejected from the crater. The bright ejecta forms a more or less continuous blanket around the rim extending to 90-150 m. At greater distances, the ejecta breaks up into a series of rays of finer material that extend as much as 1 km from the rim.
Several of the larger boulders lie at the end of shallow troughs, indicating that they slid across the surface upon landing.
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Published by Jeff Plescia on 6 June 2025