So whilst kicking the idea around, I had the daft idea of doing the space background on a separate piece of paper and cutting out the panels in the dome. I normally bin such ideas as folly long before they hit the page. For some reason this one passed unnoticed, and now I have two space backgrounds. Couldn't decide on ink or colour, so I'm posting both.
Black & white background is ink & washes. The colour one is acrylic with white & yellow inked stars.