Since the 1930s, residents and visitors to Norway’s Hessdalen Valley have reported strange glowing orbs in the sky. These inexplicable lights have been photographed and filmed day and night for many years.
According to computer scientist Erling Strand, the lights suddenly stopped in 1983 and reappeared in 1984. Strand and his team used radar, a magnetometer, a radio spectrum analyzer, a seismograph, cameras, a Geiger counter, and an infrared camera to evaluate the phenomenon.
According to the data collected, as well as eyewitness reports, the lights can move slowly and sometimes toss and follow a random path, and can last from a few seconds to more than an hour. The size of the lights was the size of a car.
What causes them? Unfortunately, we don’t know for sure, but there are a number of interesting theories.
One theory put forward by researchers in 2010 suggests that the phenomenon is caused by the decay of radon in the atmosphere, given that the Hessdalen valley (and Norway in general) has one of the highest concentrations of radon in Europe.
There is an even more interesting idea, first proposed in 2006. It lies in the fact that this phenomenon can be caused by the fact that the landscape acts like a natural battery, which then regularly discharges.
The Hessdalen valley is divided in two by a river, with zinc- and iron-rich rocks on one side of the river and copper-rich rocks on the other. The anode of this “ideal natural battery” will be a section of zinc and iron, and the copper half will be the cathode.
The only thing missing is an electrolyte solution to transfer charge between the two sections of the battery.
“The missing element to support the ‘natural battery model’ was discovered in 2012 with the reopening of local sulfur mines. They operated until 1933, but were closed due to the bankruptcy of a mining company,” the research team wrote in 2013.
“We now assume that the flows flowing from the mines into the Khesya River may contain sulfuric acid.”
The team noted that anomalies in the magnetic field were found in the area, indicating a natural battery. It is not known how this battery would produce enough charge to create such visible light, however the team suggests that the local features of the valley lead to the formation of cold plasma and/or ion bubbles.
Despite all these theories, scientists still do not have an answer to the question of what causes these mysterious lights.