Pollen corona, the 'devil's circle' for hay fever sufferers, appears in Tokyo skies
(Mainichi Japan)
TOKYO -- A pollen corona, a rainbow-like ring around the sun due to the refraction of light by pollen particles floating in the air, was observed in the capital's Chiyoda Ward on Feb. 22.
The maximum temperature on the day in Tokyo hit 21.9 degrees Celsius, the same as the average in early May.
Hay fever sufferers in Japan often call pollen coronas "devil's circles" as they're signs that a large amounts of pollen are floating about. To view pollen coronas people should use buildings, trees, utility poles, etc., to shield their eyes directly from the sun.
(Japanese original by Koichiro Tezuka, Photo Group)