In the Novgorod region of Russia, ice circles of perfect shape slowly rotating on the water surface were seen on water reservoirs.
The natural phenomenon was seen on the Lovat River in the Kholmsky District and on the Moshenka River in the Demyansky District.
According to experts, such circles appear as a result of the slow vortex current. Pieces of ice, falling into the current, begin to rotate, their edges get ground down, and ice pieces take a round shape.
