- Chapter 1 - Introduction and historical background
- Chapter 2 - Mechanism and designation
- Chapter 3 - Case example
- Chapter 4 - Characteristics
- Chapter 5 - Six Causes
- Chapter 6 - Identifying light pillars in cirriform clouds
R e s e a r c h
Data quality
Working with eyewitness testimony that is obtained from accidental observers, sometimes years or even decades after the reported event took place, is always a risky enterprise. Many of the reports that were selected when we set out to study the phenomenon appeared to contain dubious or even flawed data. The descriptions of what was observed could often be interpreted in more than one way, and basic information, such as the azimuth and elevation of the phenomenon, were almost never indicated.
Confusion
The problem of finding a sure identification for sightings of light pillars is further complicated by the existence of several other sky phenomena that can take the shape of a vertical pillar, a tear-drop or a round patch of light. In reports where date and time are mentioned, the astronomical situation was checked to see if Sun or Moon related optical phenomena, such as moon dogs and sun pillars, could not have created the confusion. Even a crescent moon shining through a cloud layer can look very similar to the phenomenon that we are interested in. Confusion with other nocturnal lights (especially contrails of aircraft, auroral pillars and chemical clouds released by rockets) is also possible, and their presence at the time of the sighting is often difficult, if not impossible, to verify, especially when the incident occurred many years ago.
The crescent moon shining through a layer of cirrostratus. Sun pillar over Lake Tahoe, Nevada. [© James KIRKPATRICK - more pictures by this photographer can be viewed at jameskirkpatrick.com]
Auroral pillars photographed over Dover, Oklahoma, during the great display of October 29-31, 2003. [Photo by Dave EWOLDT - image found on science.nasa.gov]
How to proceed
One way to find out if reflections from ground-based light sources may have been responsible for a specific sighting, is to use a detailed map of the location and look for oil refineries, chemical works, steel factories or blast furnaces in the direction in which the unknown phenomenon was situated. Aerial imagery, such as the images that can be found on Google Earth, can be of great use here. In two cases, employees at the petrochemical complex in Antwerp assisted CAELESTIA in identifying nocturnal lights by checking if there was an increase in the quantities of gases that were burned off during the sightings. Still, it was only after repeated requests and personal contacts that we were given a quick look at this data. Because of the pollution and the noise they entail, flaring activities are not good for the public image of oil and gas companies, which is why most of them are not keen on sharing this type of information with outsiders.
How you can contribute to this research project
This project is an ongoing one, and our search for information on this remarkable optical phenomenon still continues.
Wim VAN UTRECHT (July 2007)
Notes & References
[25] VAN KAMPEN, Hans, "Nachtelijke lichten boven Nederland" in Aarde & Kosmos, March 1977, pp. 133-134. |
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