Are asteroid belts and exploration sites always consistent within a system? Or do they change from time to time.
Specifically about exploration sites, are there guaranteed to always be exploration sites in each system? e.g. if I use my scanner probes and find nothing, is that just because my skill isn't high enough - or do some systems just not have exploration sites sometimes?
And specifically about asteroid belts, do they change what types of asteroids exist within the system? Or do asteroid fields change up their composition - or sometimes switch to ice fields?