APOD: Unusual Light Pillars Over Latvia (2009 Jan 12)

lestheastronomer · Post by **lestheastronomer** » Sun Dec 28, 2014 7:55 am

I suspect the fanning of the pillar is due to some dispersion and/or thinning of the ice crystal density with height.

Les Cowley · Post by **Les Cowley** » Sun Dec 28, 2014 5:33 pm

The explanation for these unusual pillars was posted on OPOD ( http://www.atoptics.co.uk/opod.htm ) some time ago. See this http://www.atoptics.co.uk/fz193.htm page. They are produced by columnar hexagonal ice crystals drifting with their long axes horizontal.

More of these pillars at -http://www.atoptics.co.uk/fz179.htm

Les Cowley (http://www.atoptics.co.uk)

Starship Asterisk*