I was wondering if it's possible to change the letter size and the font of the planet and star names. 

I have a very large map I'm working on and it all looks a bit cluttered and untidy. It's difficult to pick out a Stars name when zoomed out due to the planet names around it blocking it.

I want to change it so planet names are shown in small text and the Star names shown in a larger text with maybe a different font or colour. Does anyone know if this is even possible and where would I start?

Thanks.