One of our subscribers sent us the following question:
Great question. Let’s figure it out together. Moreover, this phenomenon has long been known to science and well studied. Indeed, at times, most often during sunrise or sunset, visible columns of light can be observed spreading up and down from the Sun.
This optical effect is called
In addition, we all learned at school that our atmosphere consists of 78% nitrogen, 20% oxygen, 1% argon and a little bit of different other gases. However, in addition to this, there is also water in our atmosphere. Its content in the atmosphere is uneven and depends on the season, latitude and longitude, and weather conditions. On average, the content of water vapor in the atmosphere ranges from 0.1% to 2.5%.
The temperature of our atmosphere is also uneven — at sea level the atmosphere is heated, but the further from the surface, the lower the temperature. As it rises, a moment comes when the water can no longer be in a gaseous state and the vapor either condenses into tiny drops of water from which clouds then form, or desublimates turning into tiny ice crystals.
These crystals are not at all like the snowflakes we are accustomed to, which have a complex structure. Almost all of these crystals have a hexagonal shape and are either hexagonal plates like the one shown in the photo, or columnar ice crystals.
Ice is known to be heavier than air. Crystals begin to fall slowly. The balance between the air resistance and the aerodynamic properties of the crystals determines their orientation in space, and in both cases the crystals are aligned horizontally or almost horizontally.
The light reflected from horizontally located crystals just forms the column of light we see. Although such pillars of light are called solar, they can also form near the moon and other light sources.
There are many different atmospheric phenomena, the essence of which is the visible appearance of light not where its source is actually located.
All these phenomena are somehow connected with the reflection of sunlight from ice crystals in the atmosphere at high altitudes or the refraction and reflection of light in the smallest drops of water (rainbow, gloria).