Been doing a little experimenting with sectors. It turns out that if we go with 100 angular segments and the bit to be mapped is on the edge then the space is very nearly cubic. As you get towards the center your angles have to increase obviously but in the center I would expect that you would change coord system to spherical since a) thats the arrangement b) the gravity there would be so immense that it would be hard to travel there and c) there would be zillions of stars there so its more of a cartographers problem than one of navigation.

So the coord system will be 100 angular units per circle and I will map 1 of them. Radially our milky way is 50,000 light years. The outer band in the image below is at 1/10th of the radius so for milky way thats 5000 light years.

List of closest stars..
http://en.wikipedia.org/wiki/List_of_nearest_stars
... means that we should have stars at about 15 light years apart or so. That means 5000/15 is 330 or so which is clearly too many to map (330x330x330)

(BTW that page has a diagram just like what I want to make but doing just a sector instead of a whole circle.

So as anyone who has star charts know they list only the brightest stars not all of them. What we would need would be the most relevant. This would mean those with inhabited planets, systems with planets possible to live on, or ones having a solid surface etc. You also need those which are big, bright and those which present a danger. We also need to mark on there outposts and non natural satellites.

So in the list of top 20 closest stars only 5 of them are of magnitude 5 or below but were still waaay off mapability.

Here is a great link to a web site with nearest stars in a 5000ly redius - perfect....
http://www.atlasoftheuniverse.com/5000lys.html
... except that it looks like clouds.

So either we need to map a whole lot less than 1/100th of the circle or we have to be far out on the rim of the galaxy or the galaxy has to be less dense or less compact than the milky way.

Might have to fudge it a bit and pic something conveniently out on the rim to give just the right density of star systems with interesting enough properties to map.

This is always the problem with astro stuff. The numbers are always just too big. I wonder if Torstan is going to do a map... now that might get interesting.