Aurelia

Aurelia was the Aurelian subsector's capital until a warp storm shoved it off its orbit, froze the cities, and swallowed the planet for centuries. Epistolary Kyras bound the Great Unclean One Ulkair here just before the world vanished and later came back tainted. When Aurelia dropped back into realspace as an ice tomb, Black Legion and Eliphas used it as a Second Aurelian Crusade beachhead among the frozen dead. This is the ice world, not the hive; Meridian took the capital job while Aurelia was gone.