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The angel figure as a dune field

In the upper centre of the images, an impact crater approximately 15 kilometres across can be seen, in which dark sands form the 'angel's head’. With a little imagination, the almost one-thousand-metre-high crater rim can even be interpreted as a halo. In several places, the layered deposits of the polar cap, consisting of ice mixed with dust, are clearly visible on the upper slopes. Even in the oval depression that forms the 'angel's hand', the view of the layered polar deposits is unobstructed.

The southern part of the images is also covered by stratified deposits. These consist of ice and dust as well, but they are much more finely layered, thinner and cover the south polar deposits. This type of deposit covers large parts of the high latitudes of Mars (approximately between 40 and 80 degrees north and south respectively), which is why it is referred to as a 'latitude-dependent mantle'. In many places, degradation phenomena due to erosion and sublimation of the ice in spring and summer are visible in the mantle, which has created several small geological windows in which the finer layer structure can also be seen on close inspection.

In the centre of the images, beneath the angel's outstretched wing, is a large, heart-shaped depression bounded by a scarp leading to another large dark dune field. The dark material, consisting of olivine and pyroxene minerals, may have come from deeper layers of deposited volcanic eruptive material or could have been blown into the depression. In the latter case, the edges of the terrain would have acted as windbreaks, causing the sands to slow down and be deposited there. This dark material is distributed globally on Mars and forms imposing dune fields in countless impact craters.