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 Received : 11/20/08  Daniel LEVIN   

There were lengthy and extensive sightings of vertical light pillars in the Philadelphia, Pennsylvania, USA last night from around 7:30 to 8:30 p.m. local time....  read more 

 Received : 11/20/08  Anthony VELGUS   

I just wanted to report seeing some light pillars last night near White Haven, Pennsylvania at approximately 00:30 Zulu Time....  read more 

 Received : 11/21/08  Anthony VELGUS   

Thanks for the explanation, but now I have another question : does the light source necessarily have to be shining directly up to cause this phenomenon or can the light be at various angles and still cause the pillar to be 90 degrees to the horizon? I do not think there are many lights in this area that send light up as most I ever see are shining down and are mostly shielded.

Anthony VELGUS
White Haven, Pennsylvania

Our reply :

The light sources that cause the vertical pillars do not have to be shining directly up. What counts is that their emitted light reaches the upper and lower surfaces of the transparent ice-crystal plates. Since these crystals are wobbling in a more or less horizontal position somewhere halfway between the light source and the observer, the angle of incidence (and therefore also the exit angle) can be quite small, especially when we are dealing with very distant light sources (see also our simplified diagram). Bright spotlights illuminating buildings and monuments, and even floodlights shining down over playgrounds or football fields can direct enough light to the sky for it to reflect of distant ice-crystal plates. In the latter case, the resulting reflections will have the shape of a series of whitish, parallel streaks close together. The number of streaks depending on the number of spotlights surrounding the field and their position relative to the observer.

Because the distance between the light source and the observer is often in the order of several miles (up to 50 km/31 miles and more!), there usually are no direct visual clues as to which lights are causing the reflections (most of the light sources will be behind the horizon or hidden from view by houses and trees).

The pillars seen over Philadelphia are also the subject of one of our case examples.


 Received : 11/21/08  Daniel LEVIN   

Thanks for the reply and the additional confirmation that is was a light pillar event.....  read more 

 Received : 11/24/08  Daniel LEVIN   

I'm sure that the phenomenon happens more than it is observed here.....  read more 

 Received : 11/20/09  Anthony FAULKNER   

On the night of November 18th, 2009 I saw about 20 light pillars in the sky above Mihonoseki, Shimane, Japan. It was very strange.....  read more 

 Received : 01/28/10  Fred ZUMPANO   

I live on the outskirts of Akron, Ohio. Tonight, Jan 28, 11 p.m., took my dog out. As I look on the horizon of this busy city, and look towards the city, vertical shafts of light are rising in the southerly sky......  read more 

 Received : 09/04/11  Andrew T. YOUNG   

This visitor response relates to Chapter 4 of our article on light pillars, and in particular to the part where we mention the observation of a "circular reflection" near the zenith produced by a combustion flame from an oil rig in the North Sea on October 20, 1993.  read more 

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