I once had such a Sun effect on Orbiter 2016. Looks very beautiful at dawn and dusk, when flying in orbit. Also looks beautiful in the Apollo project. But after reinstalling Orbiter, I just can't get it back. I don’t remember if it was an addon like that, if I did it myself in the D3D9 graphics settings, or else where I screwed it up. In general, I'm interested in how to return this effect.