The Hessdalen lights
In Hessdalen, Norway, strange lights of white and yellow have mysteriously appeared in the sky since 1940. These lights used to appear 20 times per week between 1981 and 1984. Since then, the frequency of the spectacle has drastically reduced to 10- 20 times per year. There have been theories presented about the lights, but no compelling hypothesis on its origins has ever been accepted to explain why or how it appears to this day.
