On 8 August, I was flying from Barcelona to Hungary, when I saw a faint pillar of ice crystals glistening close to me outside the window, at right angle to it. The pillar was white and the crystals were so near that I could see them individually. The sun was behind the plane at 54 degs elevation. The display lasted two or three minutes. Ideas of what it could have been are welcome.. Two original photos and their usm-ed versions are attached. Note also the other patch of glistening crystals to the left of the pillar ( 1 – 2 – 3 – 4 ).
Very strange Agnes I am not sure what would create these mystery halos. May want to consult the halo experts for that.
I wonder if this could have something to do with the pressure wave created by the plane.
I have personally wittnessed twice how a divergent light pillar (from the lamp down) changes shape as a lorry drives by the lamp. First the pillar swayed away from the truck and then towards it before settling in the center again. The pillar did not break, it simply changed it’s form in a sweeping movement and then returned to normal.
I tried to capture it on video but no more lorries came by until the crystal swarm had moved.
Photo 4 also seems to show a little arc in the upper left corner.
The pillar is very narrow. Wonder what that tells about it.
That is a good question. What a great riddle!
See the black & white image on this page. This is what I had in mind and seems to fit the halo as well.
Thanks for the ideas, Jari. This riddle-halo has been puzzling me for a while now.
maybe it is similar to show you how to here:
http://www.cs.cmu.edu/~zhuxj/astro/html/Subsun.html