Visualizing sunsets through inhomogeneous atmospheres

In this paper, it is described a method of curved ray tracing capable of depicting phenomena that arise, under certain conditions, when light propagates through an inhomogeneous atmosphere. As an example application the distortions in the spherical shape of the sun during sunsets are modelled, including split suns, flattened suns and double suns. Nevertheless, the method is general and can be applied to any media in which the index of refraction is a function of the position