Recent sub-zero temperatures across Finland have given birth to spectacular light shows.
Ice crystals in the atmosphere combined with light from the sky, or even artificial light can create the illusion of halos around the sun and moon as well as light pillars in the sky.
In extreme cold water droplets in the atmosphere freeze to become ice crystals. According to meteorologist Asko Hutila, these crystals do not usually form close to the surface of the earth, but when temperatures fall below -10 degrees Celsius they may occur. When that happens, they can refract light from the sky to create remarkable light displays.
“Pillars may appear above and below the sun if the light hits the crystals in the right way. In the dark even artificial light can cause these kinds of pillars to appear. The phenomenon is caused by the refraction of light, similar to a rainbow or a halo,” Hutila explained.
The meteorologist said that the pillars can appear anywhere, however they are mostly visible in sparsely-populated areas that are well-lit.