The day the sun turned blue: A volcanic eruption in the early 1460s

The day the sun turned blue: A volcanic eruption in the early 1460s and its possible climatic impact – a natural disaster perceived globally in the late Middle Ages?

By Martin Bauch

Historical Disaster Experiences. A Comparative and Transcultural Survey between Asia and Europe, edited by Gerrit J. Schenk, (Heidelberg 2017)


Introduction: Matthias von Kemnat, a humanist and historian of Heidelberg, wrote in 1475 a vernacular chronicle about Elector Frederick I of the Palatinate, covering the years 1452 till 1475. As he advised Frederick as an astrologist, it’s no surprise he was interested not only in the glorification of his lord’s military successes, but also in celestial phenomena such as comets. Without precise dating, he mentions that at the time Emperor Frederick III ruled, several times comets have appeared and were observed. They are stars with long tails. And the sun has been seen blue many times a day and a cross was spotted in the moon as well as many more miracles in the sky.

Research has been done on eclipses, comets and meteorites in the particular field of the history of astronomy, mainly by astronomers with additional historiographical training. A ‘naturalistic’ approach characterizes such research, as it assumes these phenomena to be real. Mainstream medievalists have been reluctant to work on celestial phenomena, and if they have done so, their work focused on the Early or High Middle Ages, on specific regions.

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Top Image: Photo by Bernat Casero / Flickr


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