An interesting phenomenon in nature, which is observed quite often, is the appearance of light columns, 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 famine. What do the light poles in the sky mean and what is the nature of their occurrence, this article will help.
What is this phenomenon?
Light poles appearing 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 low, near 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 pillar is identical to the shade of the star at this moment: if it is yellow, then the phenomenon is the same.
How do scientists interpret
Light poles are a very common version 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 rays of a searchlight is so obvious.
In fact, the light of the sun (or moon) interacts with the ice crystals formed in the atmosphere that 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 appearance of light columns becomes possible. We will understand under what circumstances this phenomenon occurs and what it means.
Light poles: how they arise, why we see them
Most often, these optical effects appear in the cold season. This is due to the fact that for the appearance of a column in the Earthβs atmosphere , ice crystals should form, and the sun should be low enough. At low air temperatures, many hexagonal ice crystals are formed in the atmosphere that can reflect light rays. But there are cases of the occurrence of a similar effect in a warmer time of the year. This can happen during the period when cirrus clouds are observed in the sky - columnar hexagonal ice crystals are also formed in them.
Sun or moon 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 makes it possible to observe an amazing phenomenon that forms at an altitude of about 8 km.
In frost, ice crystals form much lower, and due to this, light poles (photo presented in the article) have very clear contours and are better perceived visually. This spectacle is amazing - beautiful and exciting.
Education phenomenon
Scientists trace several options for the formation of the optical effect, depending on the shape of the crystals and the location of the light source. Light poles 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 serve as a prism, refracting the light beam incident on them.
- The reflected light forms a peculiar lens floating in the air and transmitting a powerful beam through itself.
- Which crystals are involved in creating such an effect (flat or columnar) depends on the location of the star at this moment. In a position at an angle of 6Λ to the surface of the earth - these are flat hexagons. If the sun is at an angle of 20 Β°, it means that the light column is formed by refraction in columnar crystals.
The phenomenon of artificial origin
So, cold and humidity - these are the main components in the emergence of favorable conditions for the formation in the atmosphere of the Earth of suspended ice crystals, faceted on six sides. They can be refracted by light from various sources - both from celestial and street searchlights or car headlights. The light refracted in them gives a specific effect, which is perpendicular to the earth, a sharply defined bright band. Residents of northern cities are witnesses of a rare phenomenon, whose name is the light forest.
This happens because the falling flat hexagonal crystals in the winter do not evaporate on the way to the ground due to subzero temperatures, but turn into a kind of thick fog that can reflect the light of ground sources and form light poles very similar to natural ones. Such rays are much longer, since the light source is located below.
Difference from Northern Lights
The nature of the occurrence of these two optical phenomena is different. Auroras are the product of outbreaks of geomagnetic storms when the magnetic field of a planet is disturbed by the "gusts" of the solar wind. It is they, intruding into the magnetosphere of the Earth, that make it glow like the kinescope of a television receiver. Usually the northern lights are manifested by greenish-purple flashes over a large area of ββthe heavenly vault.
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 examined and explanations are given of what light poles mean. The photos presented in the article clearly demonstrate the beauty of a rare phenomenon.