Hi,
Not that I've noticed.
I flew out 500 light years from the edge of any named systems into a bunch of core systems. just kept jumping and jumping until I was that far. I scanned and explored about 20 systems then returned to SOL to sell that data, in the belief that being that far in known space would increase it's value.
I still seemed to get around 210 per single star (no other planets found) and around 2.5k for a system with plenty of planets and mining spots.
btw, I was flying in an eagle with about 16 ly travel, a basic discovery scanner and that's it. I presume the price goes up in if you get a detailed surface scanner, and a better discovery scanner. Though, the only increase in value might be that you can detect more local stars.