Sideways & Vertical Light Pillars

Sideways & Vertical Light Halos

Peter Rosen pictured this icy scene at Stockholm, Sweden. Ice crystals drifting in the air have reflected building lights to give the illusion of upward light pillars. But, unusually, the brightly lit building also has sideways shafts of light apparently radiating from it. And there is more.

Image ©Peter Rosen, shown with permission

Another way of looking:

The elevation shows plate crystals roughly midway between the light and the eye reflecting downwards to produce an apparent vertical pillar.

Looking downwards we see an apparent horizontal light shaft produced by refraction and reflection from the crystal side faces. The divergent light parhelion is much the stronger.

Plate-aspect ice crystals are responsible for 'conventional' vertical light pillars. The crystals drift in cold air. Ground lights are reflected back downwards by their hexagonal faces.

Peter Rosen's sideways columns are likely created from the same crystals. But this time the main source is by refraction through the near vertical crystal side faces. The ray paths are the same as those forming 22° sundogs but the difference is that sunrays are parallel while the building light rays diverge. The divergent light parhelion is a horizontal streak. A superparhelion can also form and there are traces of it at upper left.

Reflection from the external crystal side faces forms a divergent light 'parhelic circle'. That is also a horizontal streak but rather fainter.

Many thanks to Nicolas Lefaudeux for very valuable comments.