In RP, trying to scan for a ship or station amidst huge amounts of scrap metal and all sorts of other debris in space would be nearly impossible - the ship/station would blend in with everything else.
In RP, junkers run black market trade - everything from illegal weapons to drugs and artifacts - so we need to remain fairly well hidden from lawful forces (which is why it ticks me off seeing liberty battleships hovering outside of rochester).
Out of RP, because New york is actually a fairly large system, and stations only pop up on your solars scanner tab once they're within 14k range.
You should learn how to navigate around most systems without using your map or scanners though =P If heading from manhattan to Rochester, you look at the colorado jump gate in the distance and aim about a quarter inch to the left of it. If heading from the colorado jump hole to rochester, you aim about half an inch to the right of planet pittsburgh.