During the late hours of Friday, January 27 many residents of the Russian city of Rostov-on-Don were spooked and bewildered by an unusual phenomenon as dozens of vertical light pillars were seen across the night sky over the metropolis.
However, Oleg Stepanyan, Deputy Science Chairman of the Russian Academy of Sciences’ Southern Scientific Center, told RIA Novosti that this phenomenon is in fact not that uncommon and has a rational scientific explanation.
"The appearance of such ‘pillars’ may be caused by two reasons. One of them is an optical illusion, whereby certain kinds of light are perceived by us as pillars due to atmospheric phenomena. The other reason is the combination of city lights and the so called ‘frost dust’ in the air, which I believe is what happened in Rostov, with the clouds providing a reflective effect," Stepanyan said.
The scientist pointed out that the "light pillars" were not some kind of natural phenomenon, but rather an optical illusion triggered by a sudden cold spell.
"There was a warm spell on Friday afternoon, but during night the temperature dropped to —14 degrees Celsius. As the air was humid, the water vapors started to condense and crystallize – there were basically small ice crystals, icy snowflakes forming in the air; this phenomenon is sometimes referred to as the ‘frost dust’ or ‘haze.’ When these ice crystals float in the air they reflect all light directed at them. For example, a car with its lights turned on drives uphill, and a man who stands on the other side of that hill would see a pillar of light shooting upwards. And there are plenty of places in downtown Rostov where a car can drive uphill," Stepanyan said, pointing out that even a single light source can produce several ‘light pillars.’
It should be noted that similar phenomena were also observed earlier this month in other Russian cities such as Murmansk…
Редкое атмосферное явление — световые столбы, Саратов, Россия pic.twitter.com/V93v2vxXn5— Иван Морозов (@best_roof) 22 января 2017 г.