Close Quarters

A short primer on galactic geography (astrography?). The star systems of the galaxy are divided into regions, based largely on the historical migration patterns of early spacefaring races.

Deep Core
Few habitable systems lie this close to the super-massive black hole at the center of the galaxy.

Core e.g. Coruscant, Corellia, Alderaan, Kuat
This is where the truly powerful, wealthy, and influential planets are situated. Among the oldest human-inhabited planets. Center of Imperial power. 

Colonies e.g. Neimoidia, Koensayr, Shelkonwa
The first waves of exploration reached these worlds.

Inner Rim e.g. Thyferra, Bestine, Tanaab
The Inner Rim is the outer edge of what some call the Greater Core.

Expansion Region e.g. Tierfon, Woostri, Kira
Imperial might begins to diminish as one moves further from the Core worlds. The Expansion Region has a brutal history as a group of worlds initially controlled by large corporations of one type or another. Many of these worlds were stripped of natural resources to fuel the flowering of the Core. 

Mid Rim e.g. Naboo, Malastare, Bothawui, Kashyyyk
The Mid Rim is a large and sprawling space filled with beings that like to keep to themselves. They prefer to avoid both the political problems of the Core Worlds and the rampant lawlessness of the Outer Rim.

Outer Rim e.g. Sullust, Tatooine, Mustafar, Yavin
This is the last stop in terms of the "civilized" galaxy. Most planets in the Outer Rim are a far cry from the urbanized and sophisticated worlds in the Core. Imperial might is weakest out here on the fringes of the galaxy. Beyond the Outer Rim lies Wild Space and the Unknown Regions.


The Sumitra Sector (including Tierfon) is located in a thin section of the Expansion Region, and as such, is very close to systems technically situated in the Inner Rim, Expansion Region, Mid Rim, and Outer Rim. The sector is nestled between the Hydian Way and the Perlemian Trade Route, two of the major hyperspace trading routes spanning the galaxy, and also close to the smaller Vaathkree Trade Corridor.

X-wing starfighters ranging from Tierfon are frequently sent to support raiding and resupply missions targeting Imperial cargo shipments moving along the trade corridors.








Sources
Star Wars The Essential Atlas, LucasBooks, 2009 (Wallace, Fry)