These are three consecutive shots taken from the roof of the Control Tower of Viterbo Airport, Italy.In the images you can see a 360-degree Fogbow, a Spectre of Brocken and the Glory. I took three shots to understand the position of the optical phenomena with respect to the sky and with respect to the position of the Sun. Fogbow: a fog arc, sometimes called a white rainbow, is a phenomenon similar to a rainbow; however, as the name suggests, it appears as an arch in a mist. Due to the very small size of the water droplets that cause the fog, less than 0.05 millimeters (0.0020 in), the fog arc has only very faint colors, with a red outer edge and a bluish inner edge . Colors fade due to the diffraction effect of the smallest droplets. Many think that the Glory and the Specter are the same phenomenon, but that's not the case. They are two different and distinct phenomena: the Specter is simply the shadow of the observer, while the Glory is composed of the halo and the concentric rings visible in it. The details of the Gloria in this photo are not visible. The Specter could be likened to an anti-crepuscular ray formed by the photographer's shadow. I explain the phenomena in detail: Suppose we are standing on a hill, and behind us the sun or full moon shines. Our shadow is projected onto the fog below and is apparently transformed into a pyramid-shaped silhouette with its apex at the antisolar point just where our head shadow appears. This shadow is called the Brocken Specter and was coined during observations held on the Hartz Mountains in Germany. If the apex of the shadow is surrounded by a bright sun then the Glory is observed. The observations of the phenomenon have been carried out for the most part from aircraft in flight. The glory is an antelium, or a phenomenon that occurs in the opposite direction to the star. Often the Specter can be highlighted and also accompanied by a white rainbow in the fog as well as a Glory. Our shadow seems very extensive but at most it cannot exceed thirty meters in length. In the past attempts to interpret this phenomenon were of a "mystical" type, in fact holiness was attributed to that person whose head was surrounded by a halo. The spectrum is also visible at night with artificial light sources such as the headlights of a car or a very powerful torch.
According to the physicist Robert Greenler, the halos drawn on the heads of saints in art history seem to be an interpretation/reproduction of the physical phenomenon of the Glory. The theory formulated by Van De Hulst H. C. (in "Light Scattering by Small partitions", New York, 1957) states that the rings of Glory are formed by tiny drops and ice crystals belonging to cirrus clouds or mists; according to this study, the radius of the concentric rings can vary from a minimum of 1.2° to a maximum of 8.3°.

Technical details: Nikon Z9, fisheye 8-15 at 8mm f/10, Time of exposure: 1/400, 125Iso, 42°26′03″N 12°03′44″E

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