System reference: Principle satellite moon of Castobel (aka Halsadt),
designated ‘Tantalus’, Atlas Stellarum Jericho, M.35 reference.
Population: Approximately 79 million.
Tithe Grade: Exactus—[Crusade Specis]: (The moon is host to considerable natural resources in sub-strata promethium [grade Vulcan-989] and other geologically attendant chemicals, exploitation of which is fully established and tithed to the consumption of the Achilus Crusade via Departmento Munitorum Edict.)
Geography/Demography: Tantalus is a world approximately two thirds the mass of Holy Terra in stable orbit around a type III gas giant, whose length of day, gravity, and climatic conditions point to deliberate alteration during the High Dark Age (see extant examples throughout the Segmentum, i.e. Typha-IV, Magna Borallia, Jaegers Folly et al), and was an agri-world serving the primary Castobel hive world during the period of established Imperial rule of the Jericho Sector. Over the last millennia while out of Imperial control, Tantalus has undergone a transition towards a climatic cooling associated with the slow onset of a rotational ice age and prevalent conditions on the moon are now predominately stormy, and topography succumbing to sub-arctic/tundra with polar ice caps advancing to cover 32% of the moon’s surface. Human life had dwindled considerably during the local ‘Age of Shadow’ to fewer than ten million living as pre-industrial hunter-gatherers. However, with the coming of the Achilus crusade and the resurgence of the hive world of Castobel, extensive promethium refinery infrastructure, the starport/city of Tantalus Landing and other settlements have been constructed and the population has trebled through forced immigration of tithed workers and crusade forces.
Governmental Type: Crusade Dictatorship/Departmento Munitorum Satrapy.
Lunar Governor: Quastor-Intendant Charlotta Grimes.
Adept Presence: Extensive Departmento Munitorum officio presence, sub-directorate level, minor presence Adeptus Mechanicus/Chthonic, Adeptus Mechanicus/Biologis. Other adept presence not considered noteworthy.
Military: Crusade military forces garrison station: Tantalus used as ‘second line’ rotation post for the Orpheus Salient war zone crusade forces. Median garrison levels approximately ten to fifteen thousand troops on rotation (High/High.) Additional forces of the Adeptus Munitorum provost command overseer/disciplinary corps are charged with maintaining order and ensuring production, and comprise roughly two hundred thousand operatives (Average/Low.)
Major sites of importance: Pyroclast-Gamma-9
+++Deathwatch Addendum: Code Omega-Black+++
Tantalus overran by Tyranid xeno-forms. Imperial resistance has been crushed. The primary starports and habitation zones have been lost, mainline Imperial Guard garrison effectively destroyed, lunar governance destroyed, estimated population causalities 89% and rising. Catalytic organisms now entering environmental prevalence in the Tantalus Equatorial zone—estimate twenty to seventy hours until biospheric conversion begins. Fragmented resistance holding out in the Polar Regions for the moment. However, armament and size of remaining forces totally inadequate to prevent the Tyranid swarm systematically advancing to scour the world of all life.
+++Tantalus is lost: May the God-Emperor cherish the souls of its defenders+++