Venus Pillars on Eclipse Night
All bright object can make ice crystals glint to produce pillar halos. On lunar eclipse night in Hungary, December 10, Monika Landy-Gyebnar captured those of the Evening Star. ©Monika Landy-Gyebnar, shown with permission
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I went out to see the lunar eclipse but there was no chance because clouds obscured that part of the sky. I was just thinking of coming home when I noticed that bright Venus hanging above the pine trees had an aureole with a well elongated shape. It was not yet dark and Venus was 8 to 9° high. A bit later as it came lower the oval-like shape changed to a clearly visible pillar. I think as the sky darkened the pillar became more recognizable. When the Venus reached 4° the pillar disappeared as the cloud layer ended there."
Millions of wobbly hexagonal plate oriented crystals each reflect light towards the eye to produce halos that look like vertical columns. The greater the wobble the taller are the pillar halos. Unlike most halos, pillars do not need near perfect crystals and most are formed by large imperfect ones that have a natural tendency to wobble from horizontal.
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