Click for full image.
Today’s cool image, taken on July 1, 2020 by the high resolution camera on Mars Reconnaissance Orbiter, is of a mound-like mountain on Mars that to all intents and purposes appears covered by glacial ice, some eroded, some not.
The image to the right, rotated, cropped, and reduced to post here, shows this mound. Both the flow coming down from the mountain top down the north slope as well as the flow in the north that appears to begin in a small crater suggest glacial features.
Even more convincing are what appear to be patches of glacial ice on the southern slopes, resembling the kind of glacial patches you see everywhere in Glacial National Park. The second photo to the right, taken by me on our visit to Glacier National Park in 2017, shows similar patches hugging the mountainside at Grinnell Glacier.
This Martian mountain is located in the southern hemisphere inside Hellas Basin on its eastern interior rim. (See the overview map below, with the location of this photo the small white box south of Harmakhis Valles.) Thus, you would expect the north-facing slope to get more sunlight (and more heat) than the south-facing slopes. Yet, from this image there appears to be greater erosion on the south-facing slopes. A puzzle indeed.
I have previously posted other images of glacial-like features in the region around Harmakhis Valles and Reull Valles. See:
All show, as today’s image does, what look like typical glaciers flowing down mountains’ slopes.
What makes today’s mound however even more intriguing are the features at its peak. The photo to the right focuses on the area in the white box in the first image above, at full resolution.
Up close the glacial-like nature of the patches on the southern slope is even more evident. More fascinating however are the swirls and layers at the peak. They are suggestive of many layers of glaciers, placed down, one on top of the other, during many past climate cycles, that are now being exposed due to erosion and sublimation.
This pattern also suggests that once on Mars there was more water for making ice. Once, this mountain was entirely covered with many layers at its peak. Recent climate cycles however have not produced enough new ice here during colder periods at this location to rebuild those mountaintop glaciers. Thus, wind erosion and later warm cycles have worn those layers away, exposing them.