this is a "feature" kind of ... 
there's a limit to maximum visibility of a single object and that limit is already reached with the eyes of the universe galactic achievement...
although I thought it's a bother, it gave me the incentive to build a horde of survey ships which in the end is more useful since they survey what's respawning and they watch what's happening... plus it gives me ships to convert in case there's something urgent to do somewhere ... (like a destroyed ressource starbase ...) 
