Rough-Textured Circular Feature

This circular feature is a collection of hills, with some connected by ridges.

The circularity suggests that perhaps there was once an impact crater here that was subsequently filled with material which was somehow more resistant to erosion than the landscape around it.

Over time, as erosion stripped away the ground, the fill material was left standing higher (although it has clearly been eroded as well).

Written by: Ross Beyer   (8 April 2009)

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Image: NASA/JPL/University of Arizona