Shadows...
Sol
aka the Sun.
Take note of the deformation of the lens, but a clear 360 degree response is produced from a single illumination direction. Crisp shadows, all converging in the down-sun direction.
Note the peculiar anti-sun reflection from the Moondust (seen best in the "aura" around the shadow of the photographer) (a phenomenon predicted from the appearance of the Moon and the lacvk of limb-darkening)
[And, to complicate matters, the image is a mosaic of individual pis over differtent days, with different sun angles!]