The light phenomena of the Norwegian valley of Hessdalen are one of several unexplained light phenomena around the world. Scientists have investigated it since 1981 without a proven theory of what causes the phenomena. In this article, the superposition of cosmic radiation due to local distortion of Earths magnetic field is investigated as the source of the phenomena. Hessdalen has been shown to have special characteristics in the low end of the electromagnetic spectrum and this could cause the cosmic radiation entering the valley from above to superimpose into the visible spectrum. This new theory is tested against the observed and unexplained special properties of the light phenomena, showing some promising results.