It may seem that these long rays of light high in the sky mark the location of some legendary item or mystery box, but the truth is that they are the result of a rare natural occurrence. What could cause these wonderful lightning bolts to appear which are also the source of some UFO reports?
Pillars of light over Alaska. Image Credit: Reddit/Eventarian
Extremely cold weather may not be the most pleasant environment to be in, but freezing temperatures also make for these stunning images. They can only appear when the air temperature drops below the freezing point of water (0 °C or 32 °F). For the phenomenon to occur, there also has to be a light source of some kind.
Ordinary streetlights will usually do the trick.
These colorful pillars of light over Alaska are the result of low temperatures, when tiny ice crystals form in the air. Image credits: NASA/Walter Tape
So wait, are these pillars of light coming from basic streetlights?
Well, technically yes, but a major role in the occurrence of this phenomenon is played by the hexagon-shaped ice crystals that manifest in the air when temperatures drop below 0 degrees. These usually evaporate before reaching the ground, but in freezing temperatures, flat, flickering ice crystals can also form near the ground, similar to a form of light snow. In addition, the air has to be calm and free of wind, since it can disturb the reflection of light.
These crystals consist mostly of flat plates, which tend to oriented more or less horizontally as they fly through the air. Once enough of them appear, they will reflect bright light sources placed below them. Like small mirrors, they bounce light back at us and create a pillar of light in the sky.
Illustration of snow crystals acting as “mirrors” reflecting the light source from the ground. Image credits: V1adis1av
People often mistake them for UFOs over Niagara Falls, according to EarthSky.org, where increased numbers of UFO sightings are reported when, during winter, freezing mist from descending water interacts with city lights.
In fact, they may look a bit unusual; however, they are far from being a light from space, or a UFO.
Light pillars during a cold winter night of January 2016 in Stockholm, Sweden. Image credits: Raitisfreimanis
However, not only artificial lights are capable of creating pillars of light. Our own star, the Sun, is capable of generating its own pillars of light, but in this case, solar pillar is the appropriate term to use. Solar pillars occur before sunset when the sun is low enough in the western sky, or at dawn when it is low in the east. Also, the clouds must be thin enough to allow enough light to reach our eyes to witness the pillar.
Solar pillars also appear as a beam of light, except that they extend from the sun.
Solar pillars are the Sun’s own light pillars. Image Credits: NOAA Photo Library
In fact, pillars of light are quite rare, as many factors must be met in order to see them; but once the pillars are formed, they are going to be a real visual treat for any observer.