What are Light Pillars?

A light pillar is a visual phenomenon created when a light is reflected off by ice crystals giving out roughly horizontal parallel light beams. The light can come from the sun (just before sunrise or after sunset), moon or from terrestrial sources such as streetlights. The pillars are not physically over the lights or anywhere else in space. They are purely collected beams of light reflected from all the millions of crystals, which just reflect light towards the observer’s eyes.