Rainbow colored clouds appear in Yunnan

(ECNS) -- Rainbow colored clouds are seen in the sky in Pu'er city, southwest China's Yunnan Province on Monday.

The clouds, called "seven-colored auspicious clouds", were seen before the sunset and continued for almost an hour, attracting passers-by.

It is said that the phenomenon is called "solar corona", which is the diffraction of sunlight that occurs after refraction from the sun.