This undated footage shows two suns that appear in the sky in Yibin, Sichuan Province, China, undated.

The presence of ice crystals in the atmosphere cause the image to appear to split because of the diffraction of light, which can make it appear that there are two or more suns.
However, in this particular case, Zhou Enping, associate professor of the Department of Astronomy, School of Physics, Huazhong University of Science and Technology, ruled this out.
He said the suggestion that it was ice crystals was not correct because if it was ice crystals the second image would effectively be a virtual image of the first one.
He added that the angle between the two virtual images is generally 22 degrees and that the angle between these two suns was obviously not 22 degrees.

He said that the fact that the cloud was partially obscuring the sun meant that it was not a complete circle, and then when the mobile phone user had zoomed in, the algorithm and the mobile phone recognised that a sunset was being filmed, and set to work in order to correct the shape.
But the algorithm clearly did not realise that the sky cannot have two suns, and therefore mistakenly turned the two halves into two complete suns when the zoom function was used.

The images were shot as the country experiences extremely high temperatures, with the Chinese Central Meteorological Observatory issuing an orange warning for high temperatures the light to reach up to 40 degrees Celsius.

[NOTE: undated footage]