A medieval text refers to what researchers believe to be the first UK account of ball lightning that remains unexplained today and is associated with thunderstorms.
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Researchers have found what may be the oldest known account of unexplained ball lightning in the 12th century that continues to baffle scientists today.
Ball lightning is usually reported during thunderstorms where large spherical objects of light form, from a few centimeters to several meters across, and generally last longer than normal lightning.
There are scant scientific details about their existence with some reports that they could form after lightning strikes the ground and then ignites silicon oxide in the earth.
Debate over its causes has raged over the centuries, and now Durham University Physics Professor Emeritus Brian Tanner and History Professor Giles Gasper have come across a reference to ball lightning while exploring a medieval text written more than 800 years ago.
The account by the 12th-century Benedictine monk Gervase, of Christ Church Cathedral Priory, Canterbury, predates the earliest known previous description of ball lightning recorded in England by almost 450 years, the researchers suggest.
Writing on June 7, 1195, Gervase stated that “a wonderful signal descended near London”.
He described a dense, dark cloud, emitting a white substance that grew into a spherical shape below the cloud, from which a globe of fire fell into the river.
Professor Tanner said: “Spherical lightning is a rare weather event that is still not understood today.
“Gervase’s description of a white substance coming out of the dark cloud, falling as a sphere of fire that rotates and then moves horizontally is very similar to historical and contemporary descriptions of ball lightning.
“If Gervase is describing ball lightning, as we believe, then this would be the oldest account of this event in England that has been discovered so far.”
Before the text was revealed, the first report of ball lightning from England dates back to a major thunderstorm at Widecombe, Devon, on October 21, 1638.
Gervase’s Chronicle and other works now exist in just three manuscripts: one in the British Library and two at Cambridge University.
The Latin text was edited by Bishop William Stubbs in 1879 and there is no English translation.
The researchers previously examined the monk’s eclipse records and a description of the crescent moon image split.
Professor Gasper said: “Since Gervase appears to be a reliable reporter, we believe that his description of the fire globe on the Thames on June 7, 1195, was the first completely convincing account of ball lightning anywhere.”
The findings are published in the Royal Meteorological Society’s journal Weather.
George Holan is chief editor at Plainsmen Post and has articles published in many notable publications in the last decade.