This archive tracks four layers. A record present in 2 of them (M41, IND) is silent in the rest, and says so.
The Horus HeresyM30–M31
[RECORD LOST]
No record for this location in The Horus Heresy.
Age of the ImperiumM32–M40
[RECORD LOST]
No record for this location in Age of the Imperium.
The 41st Millenniumpre-Rift
imperium
Tidally locked civilised world
One face permanently to its star and one permanently away, so it is desert on one side, ice on the other, and everyone lives in the twilight band between them. Both hemispheres were used as an argument for why it could not be invaded, shortly before it was.
Era Indomituspost-Rift
imperium
[RECORD LOST]
[RECORD LOST]
Nothing survives in the archive for Era Indomitus.
Position
Map frame: 676, 700 in the archive's 0–1000 disk space (core at 500, 500).
Distance from the core: 266 units ≈ 28.3k light years, south-east of the galactic core.
Height above the disk plane: -6.2 units — invented thin-disk jitter, deterministic per record. No published source gives any location a z coordinate.
System: Adumbria System
Books set here
1 title in the reading tracker touches this record, 1 of them as a primary location. Titles link out to the tracker.
wh40k.lexicanum.com/wiki/Planets_(List ) — Adumbria = Civilised World, with the note 'Tidally locked, one hemisphere is desert and the other ice'. Rendered desert for the lit face; the ice face is real and is described in the summary rather than being averaged away
gposlow
derived: Ultima Segmentum, no published sector. Placed trailing of Ultramar inside the Astronomican