If you have ever been privy to the phenomenon of light pillars, then you know it is truly an amazing sight.
They appear when the weather is extremely cold and form vertical columns of light beaming directly towards the sky. Here a compilation of pillars of light for December 2015.
They sometimes look like multiple fireballs heading to the sky:
They are created when light from the sun, moon, streetlamps, or any terrestrial source, reflects on the surface of a flat piece of ice crystal as shown in the diagram below:
When the light source is close to the ground, the light pillar appears above the floating crystals.
When the light comes from the sun or moon, the light pillar can appear beneath them, too, as the light refracts through the crystals.
It is truly amazing!
Light pillars typically scrape the night sky in polar regions.
But sometimes the vertical columns of light appear along with frigid temperatures at lower latitudes.
What an awesome sky phenomenon!