This is a Procedural Sun/Star shader that you can use in scenes of your own or to render images/videos of the sun.
This shader works in blender 3.0.0 it has been tested and works in 2.92 as well but because of the recent CyclesX update it renders a lot faster on 3.0.0.
HOW TO USE:
To select what shader you want to edit: Surface, Flares or atmosphere click the names in the outliner at the top right of the screen.
(Added feature after youtube recording - See in screenshots) Flare size slider in the flares shader, increase or decrease flare size all 3 sliders have to be the same for it to be round.
If you want the flares to line up with the surface texture properly you must have the following settings the same; Seed, Pattern Seed, Scale and distortion on both surface and flares material.
The kelvin value determines the colour of the surface or flares using blackbody radiation colour, to see this the kelvin or stylized slider must be on 0.
The cell flow animation slider can be keyframed to animate the ripples on the surface.
This was designed in Blender 3.0.0 using cycles with a rtx 3080 GPU, i have tested Blender 2.92 and using a CPU and it seems to work but some features might break.
Only the surface shader works in EEVEE the Flares and atmosphere do not.
Addons you need to have installed Node Arrange, Node Presets, Node Wrangler. (These addons come with the default Blender install)
If you want to make a texture using the shader put the camera at coordinates 0 0 0 rotated facing 90 degrees sideways and the camera has to be set to panoramic equirectangular.
Blenders optix denoise does not work with volumes very well so it might produce artifacts if used.
Shader has only been tested on spheres, other shapes may not work as expected.