Key facts
- Where
- Hessdalen valley, Trøndelag, Norway
- Since
- Wave of observations from December 1981
- Project
- Project Hessdalen, founded 1983
- Station
- Automatic measurement station since 1998
The observations
In December 1981, residents began reporting strange lights over the valley – at the peak in 1984–85, up to 15–20 observations per week. The lights were white, yellow or red, moved slowly or very fast, and could remain visible for over an hour.
Project Hessdalen
The project was founded in 1983 by Norwegian and Swedish UFO organisations together with researchers; since the 1990s it has collaborated with Østfold University College (Høgskolen i Østfold) and Italian researchers such as astrophysicist Massimo Teodorani. In 1998 an automatic measurement station – the 'Blue Box' – was installed, recording lights with cameras, radar, spectrometers and electromagnetic sensors.
Scientific theories
The leading hypotheses describe the lights as a natural plasma: ionised gas or dust clouds, possibly powered by piezoelectric effects from quartz-rich rock or by the valley's geology acting as a giant natural battery – copper-rich rock on one side, iron and zinc minerals on the other, with the river as electrolyte. No theory is proven, and the researchers emphasise that the questions remain open.
Questions
Are the Hessdalen lights explained?
No explanation is confirmed. Researchers consider a natural plasma phenomenon the most likely hypothesis, but the energy source and mechanism are still debated.
Can you see the lights today?
Observations are far rarer than in the 1980s, but the automatic station still records occasional events, and Project Hessdalen publishes its data openly.