As a geometric exercise, certainly possible. Will require knowing the orientation of ND to the Sun (easy enough), and then the pillar in the background that has the beam of sunlight across it, and then work backwards to work out the timing/elevation of the Sun so it would cast that illumination. Not so straight forward as the angle of illumination on the pillar is not the actual angle of elevation of the Sun.
Interesting problem you've proposed, Petra
Alex.