The most interesting phenomenon in nature, which is observed quite often, is the appearance of light pillars, as if connecting heaven and earth. Many peoples took their appearance for various omens - both good and ominous.
Someone declared them a manifestation of divine favor, and someone - a threat of severe destruction, pestilence and hunger. This article will help you find out what the light pillars in the sky mean and what is the nature of their occurrence.
What is this phenomenon
Light pillars that appear in the sky are perfectly vertical, brightly shining columns, stretching from the sun (or moon) to the earth or from it to the luminary during sunset or sunrise, i.e. when the light source is located low on the horizon. You can see them above or below the sun (moon), it all depends on the location of the observer. The color of the column is identical to the shade of the star at this moment: if it is yellow, then the phenomenonthe same.
As scientists interpret
Light pillars are a very common variant of a halo - the so-called optical phenomenon that appears under certain conditions around a light source. When you first see this phenomenon, it is difficult to believe in the natural nature of its origin - the resemblance to the beams of a searchlight is so clear.
In fact, the light of the sun (or moon) interacts with the ice crystals formed in the layers of the atmosphere, which reflect it. Such an explanation is too simple, it characterizes the mechanism of the appearance of the phenomenon, but does not clarify the conditions under which the emergence of light pillars becomes possible. Let's figure out under what circumstances this phenomenon occurs and what it means.
Light pillars: how they appear, why we see them
Most often such optical effects appear in the cold season. This is due to the fact that for the occurrence of a column in the Earth's atmosphere, ice crystals must form, and the sun must be low enough. At low air temperatures, many hexagonal ice crystals are formed in the atmosphere, capable of reflecting light rays. But it is not uncommon for a similar effect to occur in the warmer season. This can occur at a time when cirrus clouds are observed in the sky - they also form columnar hexagonal ice crystals.
Solar or lunar rays, bursting into the atmosphere at a speed of over 300 thousand km per second,collide with ice crystals suspended in the air. It is this circumstance that is fundamental for the appearance of a halo. The play of light with these ice floes allows you to observe a stunning phenomenon that forms at an altitude of about 8 km.
In frost, ice crystals form much lower, and thanks to this, the light pillars (the photo is presented in the article) have very clear contours and are visually perceived better. The sight is amazing - beautiful and exciting.
The formation of the phenomenon
Scientists traced several options for the formation of an optical effect, depending on the shape of the crystals and the location of the light source. Light pillars appear like this:
- If ice crystals have a flat hexagonal shape, then when they fall, they take a horizontal position, while columnar ones fall in even standing rows. Hanging in the cold air, they act as a prism, refracting the light beam that hits them.
- The reflected light forms a kind of lens that floats in the air and passes a powerful beam through it.
- Which crystals are involved in creating such an effect (flat or columnar) depends on the location of the luminary at that moment. In a position at an angle of 6˚ to the surface of the earth, these are flat hexagons. If the sun is at an angle of 20˚, then the light column is formed by refraction in columnar crystals.
The phenomenon of artificial origin
So, cold and humidity are the main components in the emergence of favorableprerequisites for the formation in the Earth's atmosphere of suspended ice crystals, faceted from six sides. Light from various sources can be refracted in them - both from celestial and street spotlights or car headlights. The light refracted in them gives a specific effect, which is a sharply defined bright strip perpendicular to the ground. Residents of the northern cities are witnessing a rare phenomenon, the name of which is the light forest.
This happens because falling flat hexagonal crystals do not evaporate in winter on the way to the ground due to sub-zero temperatures, but turn into a kind of thick fog that can reflect the light of ground sources and form light pillars, very similar to natural. These beams are much longer because the light source is lower.
Different from the Northern Lights
The origin of these two optical phenomena is different. Auroras are the product of flashes of geomagnetic storms, when the planet's magnetic field is disturbed by "gusts" of the solar wind. It is they who, invading the Earth's magnetosphere, make it glow like the kinescope of a television receiver does. Usually the northern lights appear as greenish-purple flashes over a large area of the sky.
The mechanism of the formation of light rays is strikingly different, so these optical phenomena cannot be confused.
In our publication, the reasons for the occurrence of an amazing optical effect are considered and explanations are given of what light meanspoles. The photos presented in the article clearly demonstrate the beauty of a rare phenomenon.
