This observation shows a small crater within the much larger Newton Crater, and is approximately 6 kilometers across.
There are gullies on the pole-facing slopes, as well as an impressive ridged floor. Is the ridged floor older than the gullies? Could the ridged unit be a moraine? This is a term denoting an accumulation of boulders, stones, or other debris.
Newton Crater, almost 300 kilometers in diameter, is located in the heavily cratered highlands of Terra Sirenum. It was named for Sir Isaac Newton.
This caption is based on the original science rationale for the observation.
Written by: HiRISE Science Team (6 April 2011)
This is a stereo pair with ESP_022122_1400 .
More info and image formats at http://hirise.lpl.arizona.edu/ESP_021489_1405
Image: NASA/JPL/University of Arizona