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light pillar
This bright light pillar surrounded by weaker specimens was photographed by Wilber THUS from his home in Doetinchem, the Netherlands. The picture was taken at about 10:05 pm on August 27, 2005. It is the first in the series of four published here. The other three pictures show the pillar through a zoom lens at different focal lengths.

To establish the azimuth and elevation of the pillar, we asked Wilber to send us a picture of a clear night sky, taken with the same camera, from the same spot, and with the camera pointed in the same direction. Knowing the date and time of such a picture, we would be able to determine the star positions and subsequently, by overlaying this new image onto one of the pictures taken on August 27, the position of the reflections as well. Proceeding in this way, we found that the centre of the brightest reflection was at an azimuth of 277° and an elevation of 21°. Next, we plotted the azimuth line on a map. Given that the reflective cirrus cloud deck was at an altitude of 4 to 5 km, and that the angle at which light reflects off this layer is equal to the angle of incidence, a simple calculation told us that the source of the reflection had to be located at a distance of approximately 24 km from Doetinchem, i.e. right in the hart of the city of Arnhem.

An Internet search further revealed that on August 27, the city was celebrating its yearly "Rijnfestival", a city festival named after the river that runs through Arnhem. A woman who assisted in the organization of the festivities later confirmed that one or more spotlights had been operated that evening from the city’s church square. The weaker pillars in the picture, which were invisible to the naked eye, were probably caused by smaller unshielded lights in other parts of the city.

While browsing through the UFO literature, we found additional witnesses to the event. Between 9:45 and 10:45 pm several people in the area had not only seen a pillar of light but had also noticed patches of light moving in different directions over the bases of some of the lower cumuliform clouds. These sightings too confirm the presence of a projecting system with multiple rotating beams.

All four pictures were taken with a Minolta Dimage 7i digital camera, set at ISO 200 with an exposure of 30 seconds at f/3.5.

[© Wilber THUS - photo used with permission (more pictures by Wilber THUS can be viewed at www.weerstation-dichteren.nl)]