You get an interesting diffraction effect (radiating beams from a single light source) that looks a little like the traditional representation of a star by photographing the light source with a small aperture (eg f/22). This is counter-intuitive - for night shots you are generally shooting with the largest possible aperture (eg, f/2.8).
This shot is the result of merging the two below images taken at about the same time of the half moon. The first has high diffraction (f/13) and the second, significantly less (f/5.6).
The images were merged using layers to add the foreground detail to the shot and the exposure time then boosted slightly to lighten the resulting combination.