This archive tracks four layers. A record present in 3 of them (AoI, 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.
Position in this era: [RECORD LOST].
Age of the ImperiumM32–M40
imperium
Mobile fortress-monastery
[RECORD LOST]
This is the era in which the Rock begins. Caliban came apart at the close of the Heresy and one fragment came through it with Aldurukh's fortress-monastery still standing; the Chapter put drives and a warp engine into the underside of that fragment and left. Where it went after that is [RECORD LOST] — published sources record where the Rock has been, never where it is.
Position in this era: [RECORD LOST].
The 41st Millenniumpre-Rift
imperium
Mobile fortress-monastery
It travels between the Chapter's recruiting worlds, carrying the Fallen in its cells and, unknown to almost everyone aboard, the Lion.
Position in this era: [RECORD LOST].
Era Indomituspost-Rift
imperium
Mobile fortress-monastery
Besieged twice since the Rift opened — by daemons who freed Luther, and by Vashtorr, who was after something sealed in its deepest vault.
Position: 352, 452 map units No system: the Rock never has one. GW's official Era Indomitus galaxy map marks it loose in the Segmentum Solar, out toward the Armageddon end of it — this is a relational reading of that marking, not a transcribed coordinate
Position
A mobile record: it carries a position timeline rather than a fixed point. The archive places it in 1 of the four eras (IND); each era section above carries that era's entry.
Books set here
4 titles in the reading tracker touch this record, 3 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/The_Rock 'a remnant of Caliban itself that survived the destruction of the world at the end of the Horus Heresy', built around the mountain Aldurukh
era-hhhigh
the Rock has NO Heresy-era record, and that is the correction rather than an omission. In hh there is no such object: Aldurukh is a mountain on Caliban with the Order's fortress-monastery on top of it, and it does not become a vessel until the world breaks under it at the Scouring. This record previously carried an hh entry docked at the Caliban system, which the renderer can only draw one way — a ship. app/src/data/space.js dockGpos() gives a docked mobile record its own galaxy marker offset from its host, and app/src/stages/system.js presentInEra() puts a hull in the Caliban orrery for any era its positions[] names — so the fortress-monastery ON Caliban rendered as a separate starship parked NEXT TO Caliban, in the one era both were the same object. A note on the position could not fix that; only absence could. The Heresy-era Aldurukh is therefore told where it actually is, in Caliban's own hh dossier
positionshigh
wh40k.lexicanum.com/wiki/The_Rock derived from — the Rock 'travels around the galaxy and visits most of the Dark Angels' recruiting worlds'; no TEXT source states a station for any era, so aoi and m41 carry no position by design
position-indomitusmedium
the Rock is marked on GW's official Era Indomitus galaxy map, in the Segmentum Solar vicinity toward Armageddon. Read relationally (which segmentum, which neighbours) and re-derived into this frame's own coordinates; nothing was traced. This is the only era for which the Rock has any published station at all, and it is a map marking rather than a text statement, hence medium
era-aoihigh
wh40k.lexicanum.com/wiki/The_Rock the aoi status was raised from [RECORD LOST] to 'Mobile fortress-monastery'. The old value confused two different unknowns: WHERE the Rock is in this era is genuinely unpublished, but WHAT it is is not — dates the vessel to the destruction of Caliban at the end of the Heresy, which is the boundary this era opens on. The position stays unstated; the object no longer does
archetypehigh
catalogue entry 2, engine-driven asteroid fortress — the reference tag is this object by name