A part of the larger Corona Acallaris sector located in the Ultima Segmentum, near Segmentum Obscuris. The sub-sector's significance lies in it's production and it's privilege of being the recruiting grounds for two chapters of Adeptus Astartes, the Hammer Guard and the Novus Krakens space marines. In total the sub-sector contains 4 systems, with a grand total of 19 worlds. Appointed by the Corona Acallaris sector's Lord Governor, Lukas Falcora, Governor Jarconic Vendi has authority over the sub-sector, and from his office on the Civilised World of Solaritus Prime he manages the sub-sector's tithes, laws, and guard on the Lord Governor's behalf.
The Solaritus Sub-Sector's 4 systems vary in size, but each is considered important to the sector as a whole, as they produce some of the sector's most valuable exports and resources. The world's are also vital to the Hammer Guard and Novus Krakens chapters of Space Marines, who use the sub-sector as their joint recruiting grounds.
- Solaritus Prime - The capital of the Solaritus Sub-sector, the civilised world of Solaritus Prime is held in high regard. Ruled by Governor Jarconic Vendi, the population of 740,000,000 citizens are located mostly in the world's two hive cities, while the rest are grouped in smaller industrial cities that dot the globe. The climate is one of almost constant rain, leading to a lush green environment far from the polluted cities, but also to flooding, so much so that the planet's capital, Hive Sealtus, has left the lower levels abandoned so that citizens are not threatened by the constant flooding. Due to the planet's history, including staving off a massive heretic invasion, the planet's citizens have become favorable recruits for the Hammer Guard
- Gabarlos - The Dead world of Gabarlos was once considered the jewel of the sub-sector, and was the home to the Hammer Guard chapter of Space Marines. Then, in 476.M40, a massive Ork WAAAGH! tore through the outer planets of the system, headed straight for Gabarlos. The planet soon became a hellish warzone as the Hammer Guard fiercely defended their home from the immense hordes of Orks. Eventually, however, the Ordo Xenos were called in, and the planet was virus bombed then burned to permanently remove the Orks, at the cost of the world. Ever since, it has sat there, a constant reminder that even the brightest and toughest diamonds can break.
- Karline - The Death world of Karline is very Important to the Hammer Guard chapter, who use the world as the grounds for their recruitment trials. The reason for this is the world is covered in toxic plants and carnivorous nocturnal animals, and is only safe during the planet's 4 hours of sunlight a day. This creates a sense of appreciation in the star, which the chapter nurtures as part of their chapter cult.
- Modago - The massive Hive World of Modago is completely devoted to production and manufacture of goods, and the citizens mostly lead lives of constant, dull work, while the upper hives are inhabited by the rich families who have earned the favor of the Planetary Governor, Stefan DeVarl. It is one of the main recruiting world's for the Hammer Guard, who find favorable aspirants in the Hive Gangs.
- Devax Victri - The Feudal world of Devax Victri is the primary source for recruits into the Hammer Guard, due to the planet's culture and political system raising many honor-bound aspirants. The world's ruling parties are separate noble families who rule over sections of land, and conscript many of the peasants under their rule into their primitive armies to fight for control of more land. The sons of these noble houses are often raised from birth to be honorable knights, leading the house's armies. Meanwhile, from orbit, the Planetary Governor observes the planet, only descending to put down any rebellions or meet with any of the heads of the noble houses.