There is a shadow on the bedrock under the arm and I don't see any marks from contact. I'm not sure they would use the arm unless it was a last resort.

I see the rover has dislodged some rocks on the way down meaning the soil isn't that hard. Lets hope there is enough soil for traction.

I saw the K-9 prototype rover maneuvering on concrete and with those metal wheels small particles of the concrete would become dislodged and gather inside the hub area of the wheel. The sound of the wheels grinding not only made me realize how heavy the rovers are but that they could slip on a incline of hard rock surfaces.

What's interesting is the semi radial fault lines of the bedrock next to irregular patterns of the arm image.

SteveS