Yes chap, it is info on systems that you may have not visited, such as the amount of planets and stars, what trade system they have and how many stations too. Also I found that the more you buy from a particular station, the more they like you.
At first I was against purchasing the info because INTREPID EXPLORER DONT NEED NO OTHER MAPS, but nosing around on the Galaxy map made me quickly realize there was no way I was going to run out of things to put on the UC list myself; and for trading the info can be very useful as you have more info at a glance instead of hitting each and every system yourself.
Your ship only has information on certain systems in it's data banks (when you look at the system maps). The information your ship has can be incomplete. Buying data from the Universal Cartographics screen allows you to update the data in your ships navigation systems. Data is also updated if you fly to the systems yourself, and if you have some of the various exploration scanners you can go out and generate cartographic data that you can sell back to the station - so that other Commanders and factions can buy it.
ETA: The data is actually held at Commander level, so you automatically load it into any new ships that you acquire
I'm assuming this will be extremely helpful when searching for systems where mining would be financially viable. Look for the system that cost mega dollars for the info. Then go there. Could I be assuming too much?
Could be... the amount you get is based on how valuable the planets, moons etc. are. You will get the maximum payout if you are the first person to discover the system/planets etc. and a decreasing reward after that. So if you are the 1000th person to discover a planet, even if it is valuable with minerals etc. you may not get a great payment as the planet is already fairly well known.
Hmm...does this affect the trade view in the gal map?
Will only trade routes to systems you have data on display? I'm out far and away from core space and the trade lanes appear to be missing a lot...thought that could just be me and what I'm trying to move.
As Keeval pointed out there's 2 uses for the Universal Cartographics:
-first is the ability to buy data of surrounding stars (sometimes this data isn't fully complete but it gives you some initial data) , this can help with current bugs like asteroid rings around systems not showing up
-second is the ability to sell data of stars you have visited that doesn't yet exist in the Universal Cartographics store ... aka if you're an explorer and just mapped a new system with many earth-like planets this is where you go to sell that data for a profit (Largest CR/cystem so far has been ~320000CR but average systems is about ~20kCR)