Lunar halo seen in China's 'pole of cold'

Lunar halo appears over Genhe city, China's pole of cold, in Inner Mongolia Autonomous Region, Jan.16, 2022. (Photo:China News Service/Liu Liping)

Lunar halo is an optical phenomena that forms when moonlight passes through ice crystals suspended in cirrostratus clouds or fog. It is also known as moon ring or winter halo.