The derelict system 89831030/4, only has a single orbiting world, Sepulchre. It lies close to the Alathrax system, but does not have a completely stable Warp route.
Sepulchre and is a barren landscape with large mountain ranges and forests scattered around the entire planet. Imperial colonies has been setup, but contact with them was soon lost. The little water that exists remains mostly frozen in scattered areas of the planet. Limited air exists in the atmosphere and supplementary air supply is necessary to work here. This world displays little life, but Imperial archeologists have uncovered massive pyramid structures, partially buried beneath the bedrock and seemingly intact. Tomb raiders that have tried to penetrate the structure have been found horribly mutilated or has disappeared altogether. The ruins believed to be of Necrontyr origin. Imperial Inquisitors of the Ordo Xenos have been assigned to study the ruins with Adeptus Mechanicus help, but have so far not arrived.