Edge of Civilization

Saleius Bassus, capitol city on the planet Athamas.

One of the furthest settled systems of the Earth Union, Aiolia is located in a particularly material-rich region closer to the galactic core. For generations it acts as the capitol for two sectors(Orseis and Hellenia) and so the five planets:

Sisyphus- rocky, rare mineral abundant, somewhat toxic
Athamas- terraformed to 0.97 habitability during the Second Era of Expansion, Castrum Gateway station
Enarete- Homeworld to the protectorate minor civilization of the Aiolian species
Cretheus- Gas Giant, ~Neptune's mass,  icy rings, sector-radius sensor array
and
Salmoneus- outer Gas Giant, 2.3 times Jupiter's mass

all see extensive development either directly or on their moons. The planet Athamas becomes a major hub for prospectors and colonists. The presence of a Castrum Gateway coupled with proximity to alien cultures and a disputed border with M-Con forces remains a source of both incredible wealth and danger. Smugglers often make their fortunes selling contraband between these factions but face harsh penalties if caught. The Union relies on the sector for deliveries of astronomical amounts of raw materials to the Gemini Shipyards and other manufacturing centers, preferring to retain many local resources as strategic reserves.

The census department(circa S.C. 533) listed a dozen different Union species(including humans) accounting for almost 87% of the population with the remainder made of over a hundred minor intelligent species, many with a presence of little more than trading outposts. As such, many structures are built with airlocks at every door so that the atmospherics can be set to the preference of those within if utilizing common gasses. Throughout the Earth Union, Athamas gains a reputation as the place where anything can be acquired...for the right price.