Posted at 3:38 PM on December 7, 2007
by Paul Huttner
Interesting phenomenon this morning around the metro and much of Minnesota. Pillars of light refracting up through ice crystals or "diamond dust" above streetlights.
Check out the explanation here.
At about 10pm on December 6th a friend called me about some odd Aurora Borealis in the NW skies here in Duluth. When I went outside to take photos, this is what I discovered.
The very next day when I was listening to MPR I heard about the light pillars. Now I'm wondering if these are the light pillars you described in your blog or the northern lights.
My guess is that its the former, because I checked various Auroral activity websites I like to regularly check and there wasn't one shred of data that pointed to that conclusion. Hoping you can shed some light (pillars) on the subject. :)
Hopefully this html works...
Okay, here's the link. http://www.flickr.com/photos/13912417@N07/2095664125
Great photo James!
I wouild have to see it in person to say for sure, but my guess is those may be light pillars.
They look to be vertical, which might suggest they come from point sources of lights near the ground such as street lights in the distance. Were there any street or other light sources in that direction?
I have often seen aurora that look like that, but they undulated diagonally across the sky.
So light pillars are a guess, but I would have to be there to know for sure.
Sorry for the double post on this topic. I tried to delete one but the computer didn't agree.
Thanks for being a great sky wathcer!
Thanks for the reply Paul! My guess is that the lights from the Miller Hill Mall created the effect. However, one aspect of the event the photo fails to capture is that other lights in the southern sky and due north were also present.
The similarity to the northern lights were truly uncanny. I was fooled myself until I heard your report on the air.
Thanks for the en"lightening" info!
This is a 20th Century phenomenon...during the night, the concentrated light reflected upwards by snow underneth streetlamps is refracted by the snow crystals in the temperature inversion, causing the illuminated columns. They would only be apparent if illuminated by the modern streetlamp-snow configuration.
BTW, the diamond dust is not just a nocturnal phenomenon (NWS Chanhassen web page) since they were observed by me in Antarctica during their summer.