Forbidden Fortress: The headquarters of the Adeptus Astronomica is the Forbidden Fortress, a remote building constructed in a sheltered crag in the heights of the mountains once known as the Himalayas, in the region formerly called Nepal.
From the outside, nothing appears to have changed. Beneath the surface, the Forbidden Fortress has chambers which run from the highest peak to the roots of the mountains, tapping geothermal wells to power the Fortress.
The most important chamber is the Chamber of the Astronomican; a vast hollow sphere carved from a single mountaintop. From the outside its appears as a gargantuan dome, for the lower hemisphere rests within the mountain itself. Ten thousand seats rise in tiers over its inner surface. Each of these faces a ball of psychic energy which dances in the centre of the sphere.
The ball is the mainfestation of the psychic energies of the Chosen as they release their power and, ultimately, their very selves into the Astronomican. The energies they release are directed into the Warp by the mind of The Emperor himself.
One hundred of the seats are emptied each day, as the psykers who occupy them fade into death and are replaced by new Chosen.
Source: White Dwarf: Issue 140 by various
Submitter: Simguinus
Hive World Terra