A Very Bright Partial Solar Halo with Parhelia and Pillars

March 14, 2024


Photographer: Glenn McCreery  
Summary Author: Glenn McCreery   

Shown above is a partial 22-degree solar halo, containing a very bright pair of parhelia (sun dogs), that I observed in Idaho Falls, Idaho, during a cold 5 degrees F (-15 degrees C) sunrise on January 8, 2024. Also note the sun pillars, extending above and below the Sun.

Parhelia are caused by refraction of light through hexagonal plate-shaped ice crystals, where the plates are approximately horizontally oriented. The horizontal orientation is due to aerodynamic forces across the crystals as they flutter downward.

Sun pillars are caused by reflection of light rather than refraction. Sunlight is reflected off the horizontally oriented faces of crystals that are slightly tipped in the direction of the observer. The upper pillar results from reflections off the lower faces of ice crystals, and the lower pillar results from reflections off the upper faces of ice crystals.

Photo Details: Taken using an iPhone 13 Mini at 8:19 a.m. (local time) on January 8, 2024. Minor straightening and cropping were employed.

Idaho Falls, Idaho Coordinates: 43.4927, -112.0408

Related Link:
Solar Halo and Sundogs over Camelot