Cool image time! The photo to the right, cropped, reduced, and rotated so that north is up, was taken on May 12, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the strange lacy patterns seen routinely in the very high northern latitudes surrounding the Martian north pole.

Located in a region of the vast northern lowland plains dubbed Scandia Tholi, such features are apparently common here. From a 2011 geology paper of the region’s geological history:

We find that Scandia Tholi display concentric ridges, rugged peaks, irregular depressions, and moats that suggest uplift and tilting of layered plains material by diapirs and extrusion, erosion, and deflation of viscous, sedimentary slurries as previously suggested. These appear to be long-lived features that both pre-date and post-date impact craters.

The small circular feature near the bottom of the picture appears to be a mesa, and might be a pedestal crater, so old that the surrounding terrain has worn away and left the hardened-by-impact crater as a butte. To its right is a larger circular mesa with its scarp well eroded into hollows. This might also be a pedestal crater, or not.

The white lacy patterns could be frost, either water ice or dry ice. That the white lace tends to favor the north-facing slopes lends support to this guess. The photo was taken in the early spring, so the thin mantle of carbon dioxide that falls to cover the polar region south to sixty degrees latitude is only beginning to sublimate away.