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In La Vanguardia Readers' Photos we can contemplate the magic of fog and its meteorological phenomena and optical effects, with the sun and twilight rays, in addition to the Brocken spectrum.
The Brocken spectrum is the seemingly enormous and magnified shadow of an observer, cast on the upper surfaces of clouds on the other side of the sun.
The phenomenon can appear on any foggy mountain slope or cloud bank. The reason why it is called the Brocken spectrum is found in Germany, where frequent fogs occur on the Brocken, a peak in the Harz Mountains.
The Brocken specter was observed and described by Johann Silberschlag in 1780. And, since then, it has often been recorded in German literature when talking about, for example, the devil and witches.
Osona is the area of Spain with the most days of fog per year (at least a hundred). In these images we can see how the sun wants to claim itself with the twilight rays. In atmospheric optics, they are rays of sunlight that appear to radiate from a single point in the sky.
These rays flow through openings in clouds (especially stratocumulus) or between other objects. They are columns of sunlit air separated by dark regions of cloud shadow.
The name comes from its frequent appearances during twilight hours (sunrise and sunset), when the contrasts between light and darkness are the most obvious.