A global phenomenon?
Approaches
A persistant riddle
When looking for possible theories explaining the Hessdalen Phenomenon, discussion quickly comes to the special geological properties of the mountain region. The soil is extremely rich of minerals and the recovery of copper and other metals has a long tradition in the region. Otherwise the region is teconically very stable, so that there seems to be no connection to phenomena like earth lights, which have been described during earthquakes.
Light phenomena similar to the Hessdalen Lights have also been reported from other regions of earth. Among them is the Yakama-Reserve in Washington, the Brown Mountain area in North Carolina and Queensland in Australia (Min-Min Lights). Perhaps granite plays an important role. It is a prevailing rock in Hessdalen, in the Columbia Basin in Washington and in the Brown Mountain Range.
Piezoelectric effects
Amongst other hypothesis, the Italian researcher Massimo Teodorani has proposed piezoelectric effects to explain the Hessdalen Phenomenon. If quartz is exposed to tectonic stress, electricity is generated, which could be amplified by the presence of iron and copper. However the energy produced during this process appears to be too weak to explain the brightness of the lights.
Radon decay
Radon is a radioactive element, which is often found in scandinavian granite. If it is exposed to the dusty atmosphere, the decay products might ionize the air and produce macroscopic Coulomb crystalls. The theory has been proposed by Pavia and Taft. However it stays unclear how the Hessdalen-Phenomenon can move against the wind direction.
Scandium and air
The spectral analysis of the Hessdalen Phenomenon revealed that Scandium might be involved. Scandium can react heavily with acid and air. According to that the Hessdalen Phenomenon could be caused by dust clouds, raised by the wind from the ground and igniting a chemical reaction. However also in this case it stays questionable, why the Hessdalen Phenomenon can move against the wind direction.
Natural battery
In 2013 Jader Monari et al. published an article proposing to explain Hessdalen as a gigantic natural battery. The theory has been featured in the New Scientist magazine print edition (10 May 2014. p.40-43). Hessdalen is split into two mountain ranges, one consisting of copper and one of iron and zinc. Sulphur from old mines is flowing in Hessja river between those two mountain ranges, building a kind of natural battery. In order to test this theory Monari and his colleagues put up a zinc and iron rock on one site of the river and and a copper rock on the other side. And indeed an electric current could be measured between the two rocks. However, the theory is not able to explain why the lights are also seen in the Øyungen area and up in the sky. And it is not able to explain the different characteristics of the phenomenon.
The Hessdalen research appears to be far from developing a theory, providing a satisfactory explanation of all properties of the phenomenon. Currently, we just see hypothetical approaches, describing certain aspects of the phenomenon. All models fail to explain important key questions:
- How to explain the many different shapes and movements of the phenomenon?
- Why is it not possible to reproduce the phenomenon in laboratory or field experiments?
- How can the partially long duration of the lights be explained?
- Which circumstances are contributing to the appearance of the lights?
Especially the fact that the Hessdalen Phenomenon does apparently not show any correlation to geographical factors (temperature, air pressure, wind intensity, season, solar activity), makes it difficult to develop appropriate hypotheses. Normally, we should expect that an atmospheric phenomenon is correlated to meteorological data. Many sightings are reported when the humidity of the air is high. However, this correlation can be explained by the fact that it is easier to oberve the lights at night. And during the night the air is usually more humid than in daytime.