A rare light phenomenon was observed in Joensuu on Thursday afternoon, when dozens of columns of light appeared in the sky above the eastern Finnish city.
The light show was particularly spectacular along the city's Pielinen River.
"The columns of light can occur in freezing weather when there is an abundance of ice crystals in the air. The light is then reflected directly upwards from the ice crystals in a pillar-like pattern," Yle meteorologist Kerttu Kotakorpi explained.
Joensuu-based photography enthusiast Sami Niemeläinen noticed the phenomenon as he was leaving work, so he decided to go home, grab his camera and tripod, and try to capture an image of the columns.
"The columns were visible for about half an hour, then they disappeared quite quickly," Niemeläinen said.
Niemeläinen told Yle that he often photographs the city of Joensuu and the surrounding environment and while he has seen the columns previously, he did not have his camera with him on those occasions.
"This time they were bright. I didn't have to edit the images much at all," says Niemeläinen.
The columns usually last for a very short time, and occur when moisture in the air forms into ice crystals. The phenomenon usually requires temperatures of minus 20 degrees Celsius or below.
The temperature was about minus 10 degrees Celsius in Joensuu on Thursday afternoon.
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