The Dexus System
Sarus was the first solar system to the settled in the expansion of humanity into the stars, about 200 years ago. Made up of 5 habitable planets and 2 gas giants, it saw the greatest military undertaking of all time as all the space-faring nations (and few earthbound) banded together to explore beyond Pluto. The planets are offically called SAR-01 to SAR-07, but most refer folks refer to them in local slang terms, Slag, Hop, Thrum, Balite, Yosem, Zambo & Pana.
The planets were settled by various militaries, turning some planets into world-sized factories, the rest given over to a mixture of research, military outposts and crew housing. Whilst not a densely populated as Solar Prime, Sarus soon filled out as families sprung up and society moved on to accepting a multiple solar system existence.
Following the Sarun Rebellion, the World Military (as it was once known) was disbanded in favour of a corporate sponsored local militia. Most of the enlisted men and women from settling in Sarus. As a result, the world there tend to be very formal and structured, with a very clear class system. And they are usually very well armed.