Right before writing this I was at ~6.5 AU and the planet my ship was in orbit of seem quite bright; it's only ~15 solar masses and IIRC you need > 50 jupiter mass for a planet to emit even a teensy bit of light. I suggest you dim planets the further they are from their closest star and by default you have dim-light vision that automatically turn on when the brightness gets too low (ie anything > 4 AU).
I think this is quite low in priority of feature requests but perhaps it would be very easy to implement, thus actually have a chance of being implemented.
Thank you for your consideration
Feature request: Planets/asteroids dim the further they are
Re: Feature request: Planets/asteroids dim the further they are
If there's a problem with planet lighting, open an issue, with which system, and preferably screenshot as well.
Re: Feature request: Planets/asteroids dim the further they are
It's not specific to 1 planet, and the further the planet/asteroid is from its closest star, the more glaring the issue is to me. EarthSky | Top 12 brightest objects in our solar system implies that anything > 18 AU [Uranus] should noticeably be dimmer.