appearance clear craters distance distant evening glowing gray grey hidden light lighting moon moonscape orbit orbiting patches patchwork phases reflection shadow shadows shape shapes sky southern-sky sunlight surface brown color colors colour colours corrosion decay deterioration edge edged edges linear lines orange purple ragged rails railways rough rust rusty sharp surfaces textures tracks uneven variations wearing weathering background cream dip Dirt dust dusty mollusc mollusk pearly pitted ridge ridges rim seashell shell smooth spiral spiraling spiralling texture turban shell turns twists bedding clay crack curls dead dehydration desert dried dried-up drought dry dryness earth evaporate evaporation heat hot Mud river bed sand Soil summer thirst weather abstract bare bark black gnarled grooves layers mottled peeling textured tree tree trunk trunk