Adding Texture to a Directional Light?

Well since the directional light is necessary to act as the sun for the skyatmosphere component, I wish to customize the look of said light for artistic purposes, to make it appear like a giant planet / star on the horizon. The image I attached is just an overlay in photoshop to show what I’m trying to achieve.

There’s 2 images actually, one w/ the photoshop manipulation and one without it.