UFO. Russia

In front of me is one of several similar letters received in the past year.

"Dear edition! August 21, I and several of my friends witnessed the unusual phenomenon. In the South-Eastern part of the sky, low above the horizon suddenly appeared a softly glowing spot-shaped. The exact dimensions of it we find it difficult to specify, because we do not know at what distance from us it was. After some dispute, agreed that the large spot diameter is about three to four diameters of the lunar disc, and small - ten times less. Spot very slowly, almost imperceptibly moved to the right, it was getting paler and finally, as if melted completely. It lasted about 5-7 minutes. The exact time of observation we noted at the time didn't know, but it was getting dark, though the stars in the sky, it seems, was not.

Could you explain what kind of phenomenon we have observed?

On behalf of a group of friends, a 10th grade student Sergey Shapovalov. Novosibirsk".

To explain the inexplicable is always difficult. Even harder - when he did not see, and know about it by the descriptions of eyewitnesses, usually not very detailed and accurate. However, you need to be fair to the observers: most of them are not waiting for that "something" at the ready with pencil and Notepad (I'm not talking about binoculars, the theodolites, the rangefinders and other things from the Arsenal of observation techniques).

We can assume a set of versions, it is quite satisfying that description. Here may be involved, and noctilucent clouds, which have been written 10-15 years ago. Or Cumulus clouds of unusual shape, known to meteorologists as "lenticularis", which means "lenticular". (Photographs of such clouds was published in the journal "Science and life", 1979, No. 8). In the polar regions, and sometimes at lower latitudes, there are various forms of the Aurora Borealis.

I don't have the ability, and would not want to give here a complete list of all conceivable explanations, which are based on known processes and phenomena. I emphasize - known, believing that modern science knows far not all that the nature is capable. The more that industrial activities of man often helps the nature to be unexpected and unknown directions. For example, polluting the atmosphere by impurities, we change its natural radiation-chemical balance. And replaceable, often not presenting the final results of this activity. Hence, unpredictable effects, and the issues that we are now waiting for an answer from science.

Here is one possible answer. In the journal "reports of the USSR Academy of Sciences" published an article of scientists of Institute of Oceanology P. p. Shirshov, "On the possible mechanism of the phenomenon diskoidna formations in the atmosphere". Its authors, G. I. Barenblatt, and corresponding member of the USSR Academy of Sciences A. S. Monin believe that one of the causes of some mysterious effects can be aerosols or other foreign particles entering the atmosphere.

For various reasons in the atmosphere (and ocean) may be a region with high air turbulence. Measurements and calculations show that the shape of such areas are very close to disc-shaped, and the radius of the disk sometimes reaches several tens of meters. Once in the region of strong turbulence, particles are retained and concentrated in it for a long time. The optical density of the disk due to this becomes greater than its environment, and when illuminated by sun or moon, it may be visible.

In conclusion, it is worth noting that the increase in the number of reported sightings of a different kind of "unidentified objects" in recent decades, a rather good agreement with the increase of air pollution.

Yuri Slyusarev, editor Department of physics "Knowledge is power"

Translated by «Yandex.Translator»