Dune shadows

A Piece of Mars: Normally I post in color, but sometimes you need to back out to the grayscale images to see the big awesome things. This scene is 4.6×2.6 km (2.8×1.6 mi); the conical hill is 1.4 km (0.89 mi) wide. Sand-laden wind from the right is blowing streamers of dunes around the hill,