The Hessdalen Light Phenomenon

Identifying the Unidentified – The Hessdalen Light Phenomenon, Norway

Hessdalen Lights: A composite picture showing the Hessdalen light phenomenon and people gathered at a lookout point to observe at night. Artwork: NaturPhilosophieThe Hessdalen Valley of Norway.  Just 15 kilometres across.  Low population density.  But why is there a blue box perched high up on the hillside, with cameras covering the valley?  What’s going on in this secluded valley?! 

The lights of Hessdalen, in Norway, started appearing late 1981, when Åage and Rutt Marry Moe described seeing a “burning fireball” in the evening sky.

The Hessdalen Light Phenomenon

A picture showing the Hessadalen light phenomenon. Here the luminous anomaly is a doublet.
A flashing light above the mountain Finnsåhøgda, Hessdalen, Norway.  Photo: Kurt Anderssen (October 1982)

And there were a lot of sightings of this unexplained luminous phenomena.

Local people reported seeing the Hessdalen lights down in the valley, sometimes close to their houses.

Some residents were frightened, and initially subject to ridicule.

What I saw was incomprehensible!


At its peak, there were about 20 sightings a week.

Hessdalen Lights in the Media

UFO Revealed Today?  TV team from USA comes to Hessdalen Source: Time Magazine

What could this strange aerial light phenomenon be?

No one could answer that question.

The Hessdalen light phenomenon soon became known to the broader public, thanks to newspaper articles, magazines and photographic media, internationally.

People arrived in the valley, hoping to see the lights for themselves.

And many of them did.

What I saw was incomprehensible. […]

That day, we were about 30 or 40 people.  And all of a sudden, this light emerged from the clouds.  It halted in front of us, before it drifted away.  We could see all this clearly, and a bit further down, another light was waiting for it.  And at that moment, all my theories of this being airplanes, meteorites or ball lightning fell apart.  These things did not make a sound.

Arne Wisth, Photojournalist

These things did not make a sound.


An animation of a fireball providing an impression of what Hessdalen lights are like. Source: TenorA long oval-shaped light phenomenon appeared to be landing.  It came up the valley along the mountainside, stopped and rotated slowly.

As it reached the top of the mountain, it turned itself vertically.  Inside this light, I could clearly see the silouhette of a bullet-shaped object.  This picture is taken with 1/60th of a second exposure.

Arne Wisth, Photojournalist

1984 – Project Hessdalen

Dr Erling Strand, the head of the Hessdalen research project, and Hakan Kayal from the University of Würzburg in front of the “Blue Box” – the automated observation station for the Hessdalen light phenomena. Photo: Hakan Kayal

The phenomenon in Hessdalen was investigated for the first time with magnetometric, radiometric and radar instrumentation in 1984 by Erling Strand and his team.

The phenomena behave very different(ly): some is moving slowly, and some lights can move very fast.  The fastest speed we have ever measured was 30,000 km an hour.  And we have also recorded the slowest speed.  We have also recorded on the radar something moving without being seen by a light, so it’s invisible but it’s a strong recording on the radar.  So there is something which is moving around.

Erling Strand, Scientist, Østfold University College


During the first decade, many strange photographs were taken of the Hessdalen light phenomenon.

The fastest speed for a Hessdalen light ever recorded was 30,000 km an hour.

The lights were difficult to capture on film due to long distances and rapid movements in the dark, even on short exposure times down to 1/100th of a second,

Shutter Speed/Exposure Time

Shutter speed can have a dramatic impact on the appearance and quality of a photograph, especially when moving objects are involved. Source: Wikipedia

In photography, shutter speed or exposure time is the length of time that the film or digital sensor inside the camera is exposed to light (that is, when the camera’s shutter is open) when taking a photograph.

The amount of light that reaches the film or image sensor is proportional to the exposure time. 1500 of a second will let half as much light in as 1250.

What kind of lights would behave in this way, night after night, in this remote environment?

Eliminating the Impossible

A picture of the Project Hessdalen mission badge - an effort to study the Hessdalen light phenomenon from 1983 to today. Image: Project Hessdalen Many efforts were made to explain these light phenomena.

Could it be aeroplanes or the light from a distant railroad reflected in the sky?  Or maybe a form of ball lightning?  Or was it satellites, planets or meteors?

But the speed and the way the Hessdalen lights moved often beneath the tree tops eliminated all such explanations.

The phenomenon remained unexplained.

An interesting thing about this phenomenon, is that we have so many different observations.  We can even categorize them…

Erling Strand, Scientist, Østfold University College

Categorizing the Hessdalen Lights

These are the main categories of light phenomenon:

    1. One category is the rapid sparkles.  These are often difficult to see/observe, because of the short time window in which they appear.  But they are caught on film.
    2. Another category is the large phenomenon, balls of light drifting down around for hours.
    3. A third category is when there are several points of light gathered together.

Special cases – other types of phenomena not seen so often.  Their looks and behaviours are quite random within the previously stated categories.  This makes it rather difficult to explain what they are.

Three main categories of Hessdalen lights, but what was the 4th category?  Was there more to this than only lights?

I have 68 observations that I can prove.  All written down.  June 11th  2006.  It was about 30 °C that day, with no clouds in the sky.  It was coming over the mountain, shaped like a cylinder.  The funny thing about it was that the Sun did not shine on the south side, but on the north side.

Bjarne Lillevold, Farmer, Hesdalen

First Measurements of the Hessdalen Lights

A topographic map showing the location of Hessdalen AMS in the valley.
Hessdalen Automatic Measurement Station was installed and set in operation on 7 August 1998. The CCD-camera has a wide-angle lens, 107°, and looks towards south-west. Source: Project Hessdalen

The witness reports had all the classic hallmarks of Unidentified Aerospace Phenomena (UAP) – also known as Unidentified Flying Objects (UFOs) – observations, leading to a massive resistance against the Hessdalen light phenomenon in the media.

This was the background for the first measurements, back in 1984.  We had instruments and made measurements when the phenomenon appeared.

Erling Strand, Scientist, Østfold University College

A small group made of enthusiasts from UFO organizations in Norway and Sweden conducted the first investigations partly supported by the University of Bergen, and with equipment from the military.

Scientific Apparatus Up a Mountain Side

The location of Hessdalen AMS or “Blue Box” relative to the terrain. Image: Project Hessdalen

Electromagnetic measuring equipment, low-frequency radio receivers, with cameras and radar were mounted on a proper site with a good overview.

Project Hessdalen Final Report (1984) detailed the equipment used:

    • Spectrometer
    • Seismograph
    • Radar
    • Spectrum Analyser
    • Magnetometer
    • Laser
    • Geiger counter
    • Infra Red Viewer

Would it be possible to capture the phenomenon with this equipment?  If so, this would be the evidence many have been waiting for.

During the first winter, 53 observations were made over a month.

These reports were so astonishing that they even drew the interest of one of the World’s foremost UFO researchers at the time: the late Dr J. Allen Hynek, the U.S. Air Force former scientific adviser for Project Blue Book, visited Hessdalen to see for himself.

Once we used laser to point to the phenomenon when it showed up, and it reacted.  It was at that time a flashing light and when we pointed the laser beam to it, it changed the flashing frequency.  It doubled the flashing frequency.  And we take it down again, it went back to regular flashing.  And we did this test 9 times and 8 of those 9 times, it changed the flashing.

Erling Strand, Scientist, Østfold University College

Powerful lights with unusual movements, observations of craft-like objects, and responses to laser beams.  What kind of phenomenon was this?

And still more peculiar reports continued to emerge.

Observing the Hessdalen Lights

Despite eyewitness reports of craft-like UFOs and signs of mysterious landings and removal of top soil in remote parts of the Norwegian marshland, the researchers decided to focus on the light observations.

This is a part of the phenomena where they have managed to obtain solid measurements and reliable data.

Could it be that the observations of luminous objects are of a totally different kind, requiring a completely different type of approach?

During the 1990s, the frequency of observations slowly decreased.

Back in the early 80s, 20 observations a week would be made.  Now, it’s more like 20 to 30 observations per year.

But the group of Norwegian enthusiasts continues their research.

1994 – A Model for Ball Lightning

In 1994, Erling Strand and his colleagues organized the 1st International Conference on the Unidentified Atmospheric Light Phenomena in Hessdalen.

Leading scientists arrived from 8 countries including the United States, Russia and Japan.

We will discuss the phenomenon, but we will also discuss what we can do about it. […]  It has been very positive, as long as things get done in the right way.  Bear in mind, a scientist’s job is to find out things we already cannot explain.

Erling Strand, Scientist, Østfold University College

Car headlights vs. Anomalous Light Phenomena

An annotated photograph comparing the light of a Hessdalen event to the village lights and moving car headlights.
Car headlights vs. Anomalous Light Phenomena: A photograph taken in Hessdalen in August 2002 shows the dynamics of a moving car observed at the same time as the apparition of an anomalous light phenomenon. Source: Teodorani (2007)/Researchgate

The theory suggesting that the Hessdalen phenomena are created by reflection from car lights, trains, or that they are in some way connected to TV and radio transmitters, are put to rest once and for all.

This conference had one important consequence that the Hessdalen light phenomenon was now being treated with more seriousness and respect.

And for the resident population of the Hessdalen valley, this was a great relief.

Many people in the Holtålen municipality have seen the light phenomenon in Hessdalen.  And the community is sincere and takes it serious(ly).  And we are sure that they are something but we don’t know and we want the scientists to take this serious(ly) and to find out what the light phenomenon is.

Ivar Volden, Chairman of the County Council

A Flywheel Principle

A rotating mechanism that holds the light orb together and delivers continuous energy, formed an integral part of the new ball lightning model being proposed.

The energy and momentum stored in this dyality flywheel are central to it, giving the ball lightning its longevity.

In addition, it would operate to maintain the size of the ball over its luminous lifetime.  At the same time, this mechanism catalyzes the release of the energy that results in the luminosity.

Once formed, the ball lightning of this model does not depend upon any external power source.  Hence, it has no need to attach itself
to anything for sustenance – as happens with St. Elmo’s fire.

The strange behaviour of ball lightning. Source: Vuyk (2017)

The ball lightning motion will be dictated by the electrostatic forces deriving from the charge imbalance and radial currents resulting from proton decay.  Since the ball lightning is a coherent but detached entity, it does not need to follow the motion of the local air (wind).

Hessdalen Automated Monitoring Station

In 1998, research at Hessdalen entered a new phase that was to prove historic.

Supported by Østfold University College, the World’s first 24/7 observatory for light phenomena was established in Hessdalen.  With generous help from one of the local farmer, a large well-equipped container was placed on one side of the valley.

A map showing the aero magnetic anomalies in the region of Hessdalen.
The Hessdalen light «highways» (red tracks) are matching impressively with the local magnetic anomalies, indicating that the observed objectts are travelling from one anomaly to another.  Source: Norges Geologike Undersøkelse (NGU)

Radar and instruments for measuring electromagnetic noises run continuously along with video recorders that are activated as soon as any unusual aerial movement is detected.

Excitement was running high.

Would it now be possible to capture the Hessdalen light phenomenon on these new instruments?

We established this in August 1998.  Back then we only had one camera.  Already after a few days, the camera captured its first phenomenon.

Erling Strand, Scientist, Østfold University College

Each minute, the photographic cameras shoot overviews that cover the valley and upload the data to the Internet.  Several observations of the phenomenon have thus been obtained from these still cameras all year round.

But what about the video camera?

Unidentified Fire Ball – October 1998 – Project Hessdalen

After a year-long wait, it finally happened.  The Hessdalen phenomenon was caught on camera.

The footage brought the Hessdalen research to a new era.

Zooming in and slowing down the film shows something really astonishing.  A second light seems to appear from underneath, joining the main light.

How could this be interpreted?

International Scientific Collaboration with SETI

At the Medicina Radio Astronomical Station, near Bologna in Italy, the scientists are scanning the Universe for signs of intelligent life, for the SETI program.

After reading about the unexplained light phenomena in Norway, an Italian team travelled to Hessdalen and had their own experience.

In 2000-2002, the joint research EMBLA Project aimed to study the electromagnetic behaviour of the unexplained recurrent luminous phenomena in Hessdalen using sophisticated radio receivers and spectrometer.

Compared to the 1984 observational period, the monthly incidence of Hessdalen light phenomena, had sensibly decreased around the period 1998-2000.

Nevertheless, the EMBLA researchers came back to Italy with a big amount of radio data, also having had the opportunity of sighting anomalous light phenomena repeatedly.

To sharpen its research, SETI is interested in debunking the myths.

If anyone can determine what physics are at work behind the Hessdalen light phenomena, they can be crossed off the list of the inexplicable.

Mapping up Local Radio Emissions

In Hessdalen, the Italians installed their own scientific instruments, including radar and electromagnetic measuring equipments.

Light phenomena are also reminiscent of phenomena that can occur in space, so mingling with astrophysicists can be very useful for the light researchers.

From August 2000 onwards, they have been supplying the Norwegian research team with valuable support.

With regards to the specific radio field, the main advantages of the EMBLA Project  over previous measurements were:

    •  a much wider frequency range (expanded with the ELF, VLF and UHF radio windows) and resolution,
    • a much higher sensitivity,
    • a totally automated mode of data acquisition.

Now, we study VLF (very low frequency) receiver in order to investigate the phenomena that are happening in this valley.

Dr Stelio Montebugnoli, Radioteleskopi di Medicina

The signals are received directly and analysed at the Bologna Radio Astronomy Centre.

Many interesting radar readings have been received from the lights, while simultaneous photographs have been taken from the Norwegian observatory.

This way, data can be corroborated.

So the data collected inside the blue box in Hessdalen is sent everyday automatically inside our server.  After that, we start the processing of the data.  […]

I would like to remember that these phenomena appear in several parts around the World, and of course Hessdalen is very interesting because from the statistical point of view, it appeared several  times.  By the way, also in Italy, in Australia, USA, Thailand and so on..

Ing Jader Morari, Radio-Astronomer


We have to study it and try to understand it.


These phenomena could give information about some unknown form of energy.  In my opinion, any kind of unknown phenomena need to be investigated.  This is the curiosity of the human kind.

Dr Stelio Montebugnoli, Radioteleskopi di Medicina

The site of the more recent “White Box”. Image: Project Hessdalen

A new container with more advanced instrumentation was assembled near the top of the Rogne Mountain in Hessdalen.

This cooperative Hessdalen Research  Association – HERA, is also planning to establish a larger permanent observatory in the valley.  This cooperation  between the Østfold University College and the Italian is an important incentive to research now producing new amazing results.

In 2004, we brought some students up here to meet the scientists from Italy.  We had several research stations, one of them on top of the Rogne Mountain.  Around 3:00 AM, things started to happen.  What we saw looked like a solid object.  Almost like a metallic cloud.  Then it moved.  We managed to photograph it 5 times.  The last object we saw had the size of a barn.  It briefly disappeared, and when it reappeared it had the shape of a fiery ball.

Bjorn Gitle Hauge installs the cameras on the Hessdalen AMS mast in June 2001. Source: Project Hessdalen

It stopped shining, and soon after two smaller lights appeared.  They crashed into the ground right over there.  As it hit the tree tops, a blue spiralling beam of light emerged.  This blue beam hits a treetop over there.  After the impact, it changes its piral movement.

Bjørn Gitle Hauge,  Østfold University College

The result of the first 4 years of study in cooperation with the Italian Institute concluded that the phenomenon exists and that it is periodically active in Hessdalen.

Identifying The Unidentified

      • The phenomenon is identified as a bright flying object, with special characteristics making it unique to science.
      • The phenomenon is more complex and diverse than expected, indicating more than one single kind of phenomenon.
      • The phenomenon is sometimes made up of separate units, that may depart or fly away.
      • The speeds vary from 0 to 8 km s-1.
      • The phenomenon seems to be able to take on pieces of plasma or energy from the ground while passing by.
      • The phenomenon seems to radiate energy, due to the light and frequent change of colour.
      • Many spectra in the optical and radio frequency range have been detected, but more data is needed to draw proper conclusions.

These scientific data are quite sensational.  We are dealing with a real phenomenon that can be observed and studied, and measured, even though it is difficult.

But why in Hessdalen?