Main inhabitants: Humans, Jalopians, Zephians
Population: 3 million
Exports: Water, methane
Atmosphere: Trace gasses
Pluto is used as a staging area for starships leaving the Sol system. It has several enourmous supply warehouses, fuel depots, and a large spaceport, as well as several other small cities and outposts. There are orbital defense platforms stationed in orbit above the dwarf planet at all times to provide defense, because pluto is such a valuable staging area for starships.
All types of ships, from cargo freighters to GDA cruisers are prepared for extrasolar voyages here. There is a city surrounding the spaceport. Pluto has a population of 3 million
There are several stations located around the dwarf planet to mine methane ice, which is convenient, because it is usually shipped directly from the Pluto's spaceport.
Charon has an ice extraction facility to provide water for the spaceport on pluto and the starships departing from pluto. The water is also used to produce hydrogen. It has a population of 35.
Nix and Hydra
Nix has a small space-traffic control center to manage the traffic arriving and departing from the spaceport on pluto, and Hydra houses a few automated defense cannons, but not much else.