Personally, I categorise finds either as practically infinite or finite. When there are millions (and more) of them out there to be found, they are practically infinite. Otherwise, they are finite, and as such, steadily running out. So, if you're interested in such a category, best to get going ASAP.
Planetary nebulae are definitely in the finite category. Even in the core, the possible number of them would be in the thousands or tens of thousands, but since they are visible on the galaxy map, either they are likely to have already been visited or very hard to spot. The tiny PNs, as mentioned above.
In pretty much any of the finite categories though, the low-hanging fruit have been picked, so what's left takes more effort.
There is one category though that I'm fairly certain has run out: (reachable) real planetary nebulae. Undiscovered systems around the "large" real nebulae still exist, but if you wanted your very own planetary one, then you'd be late to the party.
Planetary nebulae are definitely in the finite category. Even in the core, the possible number of them would be in the thousands or tens of thousands, but since they are visible on the galaxy map, either they are likely to have already been visited or very hard to spot. The tiny PNs, as mentioned above.
In pretty much any of the finite categories though, the low-hanging fruit have been picked, so what's left takes more effort.
There is one category though that I'm fairly certain has run out: (reachable) real planetary nebulae. Undiscovered systems around the "large" real nebulae still exist, but if you wanted your very own planetary one, then you'd be late to the party.
You'd not consider what as exploration, FSS scanning a system? A honk and FSS scan is just where exploration of a system begins; Getting out there and visiting the bodies to eyeball them, and DSS, maybe even set down on some of those applicable, is to me what exploration is. Or are you meaning something in a broader (or different) sense?
