At dusk about 8 pm, three "suns" suddenly appeared and illuminated the sky above Leshan City, Sichuan Province, lasting for about 10 minutes on July 26, Sichuan News reported.
"This remains a mystery and needs a comprehensive analysis," said Professor Wang Sichao, a researcher of the Purple Mountain Observatory of the Chinese Academy of Sciences.
The "suns" attracted plenty of attention. According to photographer Lu Shan, the objects first appeared in the west. After about ten minutes, the objects moved northward and their diameter gradually narrowed.
"As they faded, they were moving like the sunset, and the light was quite gentle," Lu said.
Some people talked of a UFO invasion, but Lu, after conducting some informal research, believes it's a type of reflection from the sun or another strange phenomenon.
According to Wang, a sundog, or known scientifically as a perihelion, is a common bright circular spot on a solar halo. It's an atmospheric optical phenomenon primarily associated with the reflection or refraction of sunlight by small ice crystals making up cirrus or cirrostratus clouds.
However, the professor added that on that night the region shouldn't have had any sundogs.
"It's quite strange," Wang said.
He suggested that more photos taken from different areas and more witness reports are needed to solve the mystery.
When sunlight passes through the sides of a flat crystal, both the angle of the sun's rays and the orientation of the crystals affect the shape and color of the sundogs. Misaligned or wobbling crystals produce colorful and elongated sundogs, while light passing through the crystal in non-optimal deviation angles (up to 50°) produces the "tail" of the sundog that stretches away from the sun. As refractions are dependent on wavelengths, the sundogs tend to have red inner edges while the colors farther from the sun tend to be more bluish-white as colors increasingly overlap.