Accurate Space Lighting?


I’m new to UE4, so some of the basics on using the built in lighting system I haven’t grasped yet. Basically I want to create an accurate representation of space (specifically orbit around earth), though I’m having trouble overriding the default parameters of directional lighting and atmospheric fog to get the result I’m looking for.

I want space to appear as it does in reality, totally black except for the single bright light source of the sun. I can delete everything in the scene and make a directional light for this effect no problem, but I can’t get a sun disc to show. I followed a few tutorials and I’ve been told to use Atmospheric Fog to create the sun disc and link it with the directional light, but I can’t make everything black without the sun disc disappearing. Is there a way to have the sun disc with everything else black?