Established working geometry; several derived parameters remain approximate.
| Classification | 600.20:10:01 |
|---|---|
| Model state | Working / established scale model |
| Recovered | 22 September 2026 |
| Parent | 600.20:10 — general arrangement, scale and global geometry |
| Open parameters | Exact stellar mass/radius, final ring cross-section, local topographic envelope, and detailed latitude-dependent geometry. |
The inhabited surface lies roughly 1.5 million kilometres from a very small star.
The current working model places the inner inhabited radius at approximately 1.5 million km. The central object is a red/brown-dwarf-cusp star treated provisionally as roughly seven per cent of solar scale in the design discussions. A scale-study convention used a 6 m model stellar radius representing about 60,000 km real radius and a 150 m inner radius representing about 1.5 million km.
The scale-study numbers are design constraints, not an independent astrophysical solution. The stellar model remains subject to factual-reference testing.
The star is small in physical radius but large in the sky.
At the adopted separation the star presents an apparent disc of roughly nine degrees in the working visual model. Its effective temperature has been treated at about 2,075 K, producing copper-red illumination with much of the output shifted into infrared. A provisional visible-light target around 15 klux was adopted for rendering and environmental reasoning.
The large apparent disc softens shadows. This is an important environmental cue: the inner surface should not read as ordinary terrestrial sunlight merely recoloured orange.
The landscape is open to a retained atmosphere rather than enclosed beneath a roof.
The working scale studies use an atmospheric vertical extent of approximately 60 km above the inhabited surface. This is not a hard pressure boundary: atmosphere pools toward the rotating surface under artificial gravity and thins with altitude. Consequently tall terrain and polarward structures encounter progressively lower pressure and stronger environmental exposure rather than a literal ceiling.
Geometry couples almost every other Station system.
The radius and rotation rate determine artificial gravity (600.20:20); stellar distance and spectrum constrain illumination, heating and energy collection (600.20:50, 600.20:60); atmospheric depth constrains mountain height and high-altitude habitation; and the immense circumference drives the need for layered long-distance transport (600.20:70).
Recovered values are not all equally settled.
The 1.5 million km inner radius, Mars-like surface gravity target, approximately 24-hour rotational day, open atmospheric model and copper-red stellar illumination have become recurring working constraints. The exact stellar parameters and photometric values remain approximate and should not be promoted to immutable canon without further modelling. Likewise, the 60 km atmospheric figure is a useful engineering envelope rather than a sharp atmospheric edge.
This record preserves the current model, not its whole development history.
The geometry emerged through repeated scale, lighting, atmosphere and rotation discussions. Those intermediate calculations, abandoned alternatives and revisions belong in 400 Development Records. Astrophysical and atmospheric sources used to test these values belong in 700 Factual References. Fictional megastructure comparisons belong in 750, and any Tribunal-era specification asserting these dimensions in-universe belongs in 100 Universe Records.