Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on December 2, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and was labeled by the science team as showing “dramatic cliffs and swirls in mound-skirting unit.”
I estimate the tallest point of this cliff butte to be somewhere between 500 and 800 feet high. And while the cliff is what first attracts the eye, one mustn’t ignore the vast amounts of dust and sand that cover everything here. The small teardrop-shaped buttes on the upper plateau suggest the prevailing wind direction there is from the north to the south. However, the north-south orientation of the ripple dunes on the floor below suggests that the prevailing wind direction below the cliff is east-west. Explaining how the topography could so quickly change the prevailing wind direction is beyond my skill.
The swirls mentioned by the scientists can be seen at the top of the cliff (on the left) and just below its base, in areas where there appears to be less dust. Those swirls reveal the many geological layers here.
The black dot on the equator about 550 miles east of Opportunity on the overview map to the right marks the location of this cliff, on the northwest interior rim of 285-mile-wide Schiaparelli Crater, one of the larger craters on Mars and also one of the oldest, its rim and interior much changed with many layers formed by Mars’s endless climatic and geological cycles, some caused by volcanic events and others by the repeated swings of the planet’s rotational tilt. The swirling layers in this picture illustrate those past events.
This location, on the equator, is dead center within the dry equatorial regions of Mars. Thus, at this moment in Mars’ geological history it is wind and sand that is changing its face.
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