So what are the natural lights in this world? I think I can give you examples like the sun, the sky and the stars. Corona is also included in the natural light category. It is a type of plasma “atmosphere” of the Sun or other celestial body, extending millions of kilometers into space, most easily seen during a total solar eclipse, but also observable in a coronagraph. Light from the corona comes from three primary sources, which are called by different names although all of them share the same volume of space. Photosphere can also be considered a natural light because it is a spheric surface perceived to emit light. Another that I did not believe at first is the Milky Way! It is a spheric surface perceived to emit light.
The lightning is also a natural light. Sprites are large-scale electrical discharges that occur high above thunderstorm clouds, or cumulonimbus, giving rise to a quite varied range of visual shapes flickering in the night sky. They are triggered by the discharges of positive lightning between an underlying thundercloud and the ground.