What happened
Hessdalen is a remote 12-kilometre valley south-east of Trondheim with only a couple of hundred residents. Odd lights have been reported there since at least the 1930s, but from December 1981 they appeared so often, up to 15 or 20 times a week, that the valley filled with overnight sightseers. Witnesses described white or yellow lights that hovered for an hour or more, often below the surrounding ridgelines, sometimes just above rooftops; brief blue-white flashes; and clusters of lights moving together as if attached to one object. Some drifted slowly, others accelerated to great speed. With no official body interested, Norwegian and Swedish UFO researchers formed Project Hessdalen and, in January and February 1984, ran a five-week field campaign in deep snow with cameras, radar, a spectrum analyser, magnetometer, seismograph, Geiger counter and laser. They logged 53 lights of unknown origin. Since 1998 Østfold University College has run an automatic monitoring station, and Italian researchers have joined the long-term study.
The official explanation
Some Hessdalen sightings have been identified as stars and planets, aircraft, car headlights and mirages. For the residue, scientists have proposed natural explanations rather than craft: combustion of airborne dust containing scandium and other elements from the valley's mineral deposits; charges generated by stressed quartz-bearing rocks (piezoelectricity); dusty-plasma models by Gerson Paiva and Carlton Taft; and a 'geological battery' in which the valley sides and the Hesja river act as electrodes and electrolyte. None has been accepted as complete.
The anomalous case
Hessdalen is one of the few places where a UFO-type phenomenon recurs reliably enough to be studied with instruments, and the instruments recorded something. During the 1984 campaign, Erling Strand reports that lights were tracked on radar, sometimes when nothing was visible, with speeds ranging from stationary to tens of thousands of kilometres per hour, and that about 40 percent of sightings coincided with magnetic pulsations. No heat signature or burn marks were found despite intense brightness. J. Allen Hynek, the former Project Blue Book consultant, visited the 1985 project and called it a UFO laboratory. Decades of research by university scientists have produced competing theories but no accepted mechanism, so the lights remain, in the strict sense, unidentified aerial phenomena.
The strongest argument that this was something genuinely unknown or classified, with each claim attributed to the person who made it.
Documents
- The Hessdalen Phenomena (Erling Strand, EGU 2011 poster) report, presentations.copernicus.org
Sources
- Hessdalen lights Wikipedia
- The Hessdalen Phenomena (EGU General Assembly 2011 presentation) Erling Strand, Østfold University College
- The Hessdalen Mystery Lights QSL.net (W5WWW)
- Project Hessdalen Project Hessdalen
Witness reports elsewhere
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