I'm imagining that one can scan and detect some ships on the other side of a system, even if they can't really tell what kinds of ships they are, and then at some closer range they can get more details, etc. Same with planets and their satellites; one can see a planet from a long way away and maybe some of its moons but will get much more detailed information when closer. The range that sensors need to effectively target a fighter for weapons fire might be much smaller than the range needed to determine the composition of the rings of a gas giant.
How do people generally handle these things? Are there standard ranges at which various sizes of objects or details of their composition become apparent, or do players have to actively scan to find the moons and asteroids that might be good sources of raw materials?