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In Las Fotos de los Lectores de La Vanguardia we can see the specter of Brocken accompanied by an arch of fog over a hazy sea at dawn in Vilanova de Sau, Osona region.
After the rains on Sunday afternoon, fog covered the Sau valley and, with the first light of the sun, this double optical effect was produced from an elevated area.
The Sau reservoir is located in this municipality, which, at the time of taking these photographs, was still with a very low water level, although in the image we can see it covered in a sea of ​​fog.
The Brocken spectrum has the colors of the rainbow but inverted, while the arc of fog is white or with very weak colors and can form, as on this occasion, around the spectrum.
The reason why it is called the Brocken spectrum can be found in Germany, where, as in the Catalan region of Osona, frequent fog occurs on the Brocken, a peak of the Harz mountains.
The Brocken specter was observed and described by Johann Silberschlag in 1780. Since then, it has often been recorded in German literature when talking about, for example, the devil and witches.
