Meh, I just put it down to the interstellar medium. You're looking at light reflecting off the minute particles of gas and dust surrounding the system you're in.
You mean like in the Sol system, where the galaxy naturally has that warm orange tint? Oh, wait!
In this case I really can't RP it away. Most systems don't have a nebula around them to tint the background and all the light sources... I mean, the tint even affects your HUD. When in discovery mode and in a system with a bright orange sun, the blue lines are purple.