Re: Sphere Guides

...on top of my head:

- trade details (see Jason Hosler's reply)
- natural resources (asteroid belts-> metals/ores, wood, food,...)
- level of piracy plus details (which routes, location of the pirate's 
lair,...)
- major spelljamming groups that are active in the sphere (IEN, sindiath 
line, scro, churches, seekers, etc...)
- special conditions (temperature, uncommon natural laws)
- sphere "geography" (descritions of planets/worlds plus distances between 
them, ports of call for spelljammers)
- NPC's and ships 
- (random) encounter table for individual spheres
- adventure hooks