The Mystery of the Hessdalen Lights

"Aurora Borealis" by Victor Habbick at

“Aurora Borealis” by Victor Habbick at

Some of the most interesting comments that readers place on this blog discuss global mysteries, such as the posts on Witches Broom and Bioterrorism in Brazil or the Vela Incident. One particular case is attracting new attention to central Norway, where residents of Hessdalen have described seeing lights in the sky since at least the 1940s. People began to document this phenomenon consistently beginning in the 1980s. Unlike the Phoenix lights or Shag Harbour, cases beloved by those interested in UFOs, these lights drew sustained scientific research, because they recurred and were consistently documented by different technological means, such as spectral measurements of the lights.

In 2009 a documentary, “The Portal: the Hessdalen lights phenomenon” drew media attention to this topic. This well-made and thoughtfully written documentary described scientists’ efforts to record and understand the phenomenon. The work of the initial scientists seemed so promising that the project soon became an international collaboration between Norwegian scientists and the Italian National Research Council. Although the lights have been seen less frequently since the 1980s, people continue to monitor the skies over central Norway. Indeed, there are live cam images from the valley that you can access at this website.

The world is filled with strange but natural phenomenon: red sprites, blue jets, sun dogs, lenticular clouds, and Morning Glory clouds, to name just a few. Marcel Minnaert was a Dutch astronomer who published a classic book, Light and Colour in the Outdoors, on optical phenomenon from mirages to halos. While not always an easy read -spoiler alert, there are equations- the clear explanations and images still make this book essential for anyone interested in astronomy or meteorology. Are there plausible scientific explanations for the Hessdalen phenomenon?

In 2012 Paiva and Taft published a 2012 article “A Mechanism to Explain the Spectrum of the Hessdalen Lights Spectrum” in Meteorology and Atmospheric Physics. This peer-review science article suggested that the best explanation for the light’s spectrum would seem to be a cold plasma, and that the spectrum was unlikely to be the result of instrumentation errors: “Thus, probably, the HL spectrum is caused by high energy electrons in the thick atmospheric plasmas accelerated upward by electric field from rocks under the ground (Paiva and Taft 2012) forming a thermal bremsstrahlung spectrum with flat top and steep sides of an optically thick plasma in ID image.”

Other scientists have focused on documenting the phenomenon. In 2004 Masimo Teodorani published “A Long-Term Scientific Survey of the Hessdalen Phenomenon” in the Journal of Scientific Exploration. In this work, Teodorani described the bizarre phenomenon of the lights, such as “the capability to eject smaller light balls, some unidentified frequency shift in the VLF range, and the possible deposition of metallic particles” (Abstract). While Teodorani emphasized the difficulty of explaining the phenomenon, he suggested that “some of the observations can be explained by an electrochemical model for the ball-lightening phenomenon.” (Abstract).

The scientific literature on this topic is too large to review in a single post, and I do not have the background in physics to do so. But Caroline Williams has an interesting article in New Scientist titled “Light Fantastic,” which describes how scientists now hypothesize that the valley may have some unusual properties that lead it to generate ball lightening. In brief, different minerals on opposite sides of the valley may act as a natural battery. Jader Monari (Institute of Radio Astronomy in Medicina Italy) and Romano Serra (University of Bologna) created a model of the valley using rocks from opposite sides, which successfully generated current. In this model of the phenomenon, the lights are the creation of the valley’s geology. But it is one thing to demonstrate that the mineralogy of the rocks can create current, and another to document this phenomenon at scale. The article points out that the displays seem to be especially awe-inspiring during the aurora borealis, and that this may be a clue. The article ends by saying that more work remains to be done, and that explanations at this point need to be further developed. While this hypothesis awaits further testing, it’s good to see scientific models emerging to help explain one of the globe’s strangest and most enduring mysteries.

I’d love to hear the thoughts of any scientists -and all readers- on this topic. Does this seem to be a plausible hypothesis? What are the strengths and weaknesses of this idea? What other models might account for this optical phenomenon? Want to read about more global mysteries? Click here. Or you could read my new book Dangerous Spirits: the Windigo in Myth and History, which examines an Indigenous tradition regarding an evil spirit. In Canada the book is now available at or from the publisher. The book is also available in Kindle in the United States and Canada, as well as other formats such as Google Play BooksNookKobo and iBooks. The print launch for the United States is set for April 2015. Lastly, if you would like to read about a true unsolved mystery, please read my blog post about the ghost ship called the Baltimore.

Shawn Smallman, Portland State University


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