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
necron
Necron frontier world of exiles
Frozen, polluted and permanently raided — the posting the Ithakas Dynasty gives to the members of it that it wishes would stop existing.
Era Indomituspost-Rift
necron
Evacuated
The orks raiding it turned out to be running from something, and the something was an Imperial crusade. Its exiled lord took his dynasty off-world rather than die on it.
Position
Map frame: 66.6, 400.9 in the archive's 0–1000 disk space (core at 500, 500).
Distance from the core: 445 units ≈ 47.3k light years, west of the galactic core.
Height above the disk plane: 2.4 units — invented thin-disk jitter, deterministic per record. No published source gives any location a z coordinate.
System: Sedh System
Books set here
2 titles in the reading tracker touch this record, 1 of them as a primary location. Titles link out to the tracker.
Every fact in this record, and where it came from. Editorial derivations say so.
classhigh
wh40k.lexicanum.com/wiki/Sedh 'frozen and polluted frontier world of the Necron's Ithakas Dynasty where only the disgraced and exiled of the Necron dynasty dwell'
gposlow
inferred: no segmentum, sector, subsector or system published, and the Ithakas Dynasty article places nothing either. No segmentum is claimed; unsurveyed rim, no positional information