Technical blueprint · Blueprint
Blueprint·Concept definition, revision A

Technical blueprint

Plan, section and elevation, dimensioned. Every module drawn to scale, with the volume, mass and power budgets the rest of the concept has to live inside.

372 m³pressurised
48.3 tlanded
88 kWinstalled
Section 01

Plan view

Hub and spoke, with four modules on 15 metre centres around an eight metre core. The spacing is not arbitrary: it is the shortest run that keeps a breach in one spoke from propagating, while staying inside the 2.2 metre connector length that can be pressurised without intermediate structure.

Habitation core⌀ 8.0 mEVA airlock⌀ 4.0 mLaboratory⌀ 5.0 mGreenhouse bay⌀ 5.0 mObservation cupola⌀ 4.5 m15.0 m15.0 m35.0 m overall15.0 m15.0 mAAPlan viewScale 1:130 · dimensions in metres · long section marked010 m
Overall footprint is 35 metres across the east west axis and the same north south. Every module can be isolated at its connector. The long section, marked in orange, cuts through the laboratory, the core and the greenhouse bay.
Section 02

Long section

The section is where the shielding decision becomes visible. In the built increment there is no cover over the vessels. Each hull stands on a compacted regolith skirt that rises to a fifth of its height, with a flat band half a metre wide against the hull and an outer slope of about 30 degrees, so the skirt anchors the vessel and protects its foot without loading it. The two metres of regolith the radiation document calls for goes over the vessels in a later increment. The storm shelter under the core deck is the radiation protection that is built.

Habitation core148 m³Laboratory54 m³Greenhouse bay54 m³Storm shelter12 g/cm²1.0 m5.5 m35.0 mSection AALooking north · skirt hatched, one fifth of hull height · scale 1:90
The storm shelter sits below the core deck, surrounded by the water and waste tanks the base carries anyway. Water is an excellent proton shield per unit mass, so putting the tanks around the shelter costs nothing that was not already in the budget. The skirts are cut on the section line, so they show in full only outboard of the laboratory and the greenhouse bay; between the modules the connectors pass through them.
Why the vessels stand clear

A pressure vessel is designed to be pushed outward by its own atmosphere, not crushed inward by soil, so nothing is heaped on the hulls. The skirt stops at a fifth of the hull height: enough compacted regolith to anchor the foot of each vessel and protect it, and low enough that its load goes into the ground rather than into the structure. When bulk shielding is placed in a later increment it will have to be carried the same way, on the ground around and over a self supporting form rather than on the hull. That is the increment two job in the construction document, and until it is done the storm shelter is the crew's radiation protection.

Section 03

Elevation

Everything on a common ground line, with a person for scale, because no drawing means much without one.

Habitation coreLaboratoryEVA airlock, in frontGreenhouse bayComms towerSolar fieldISRU plant1.8 m9.5 mSouth elevationCommon ground line · scale 1:110
The comms mast is the tallest thing on the site, and it is tall for a reason: on a smooth sphere the horizon is about 1.86 km times the square root of the antenna height in metres, so height buys coverage more cheaply than any other component. The communications document and the tour carry the mast at 8.5 metres. Every module stands clear above its skirt; the bulk shielding is not drawn because it is not yet built.
Section 04

Module elevations

All five pressure vessels and the connector, drawn to a common scale so the proportions can be compared directly.

Habitation core⌀ 8.0 × 5.5 m148 m³ · 9.4 t5.5EVA airlock⌀ 4.0 × 4.5 m42 m³ · 3.1 t4.5Laboratory⌀ 5.0 × 5.0 m54 m³ · 4.6 t5.0Greenhouse bay⌀ 5.0 × 5.0 m54 m³ · 5.2 t5.0Observation cupola⌀ 4.5 × 4.5 m36 m³ · 3.8 t4.5Connector⌀ 2.2 mModule elevationsCommon scale 1:70 · heights to the dome crown
The core is twice the diameter of the airlock and holds three and a half times the volume, which is the square law doing the work. This is the argument for one large module rather than several small ones, and the compartment argument in the other direction is what settles on five.
Section 05

Volume budget

Pressurised volume is the currency of a surface habitat. Every cubic metre has to be launched, landed, and then shielded, so the sizing follows what analog crews have actually tolerated rather than what would be comfortable.

Diameter and height are outer hull dimensions. The volume column is the pressurised budget carried across the site, and it is smaller than the outer geometry implies: an 8.0 by 5.5 m cylinder encloses about 276 m³, not 148. Treat the volumes as budget figures until the structural definition closes that gap; the modules page carries it as an open item.

ModuleDiameterHeightGross volumeNet habitablePer crew
Habitation corequarters, galley, medical8.0 m5.5 m148 m³112 m³28.0 m³
Laboratorycuration and bioscience5.0 m5.0 m54 m³38 m³9.5 m³
Greenhouse bayhydroponic, six tiers5.0 m5.0 m54 m³22 m³5.5 m³
EVA airlockextravehicular activity, suit ports and dust lock4.0 m4.5 m42 m³31 m³7.8 m³
Observation cupolaand comms4.5 m4.5 m36 m³26 m³6.5 m³
Connectorsfour spokes2.2 mhorizontal38 m³34 m³8.5 m³
Totalvariesvaries372 m³263 m³65.8 m³

Net habitable is what is left after racks, stowage and equipment. Sixty six cubic metres per person compares with the 25 m³ net habitable per person that NASA's human research programme sets as the minimum for long exploration missions, and with about 64 per person in NASA's two crew reference surface habitat, so this is generous by spaceflight standards and modest by any terrestrial one.

Section 06

Mass budget

Landed mass by subsystem Power, including the reactor 8894 kg two thirds is the fission unit Pressure vessels, dry 28700 kg the five modules and connectors Life support 2014 kg Thermal control 1620 kg radiators dominate ISRU plant 1000 kg pays for itself in 18 months Construction equipment 3400 kg gantry, excavator, hauler Communications 340 kg Crew systems and medical 428 kg three quarters is exercise hardware Consumables, first rotation 1890 kg before the loops close 48,286 kg landed across four increments. At roughly a million dollars a kilogram, this is the number every other decision on the site is arguing with.
The pressure vessels are 59 percent of the landed mass and cannot be reduced without reducing volume. Everything else on the site exists to make that mass survivable, and the in situ resource utilisation (ISRU) plant exists to stop the number growing every year.
48.3 ttotal landed
28.7 tpressure vessels
8.9 tpower system
2.6 kg/dayresidual resupply
Section 07

Power budget

LoadContinuousPeakSheddableNote
Habitation corecrew systems6.8 kW9.2 kWNoLife support, galley, lighting, avionics
Greenhouse lighting18 h photoperiod14.0 kW14.0 kWPartlyPhotoperiod can shift, not stop
ISRU plantelectrolysis14.0 kW16.0 kWYesThe only large flexible load
Laboratoryinstruments and freezer3.9 kW5.1 kWPartlyThe freezer is not sheddable
Thermal controlpumps and heaters3.4 kW6.2 kWNoRises to 6.2 kW at night
Airlock and suit servicingduty cycled1.4 kW4.8 kWYesPeaks during EVA prep
Cupola and communications1.5 kW1.9 kWNo
Construction equipmentgantry and excavator9.0 kW16.0 kWYesDaylight preferred, not required
Total54.0 kW73.2 kW39 kW sheddableAgainst 88 kW installed
The number that sizes the reactor

With the ISRU plant and the construction equipment shut down, the habitat modules still draw 27.6 kW, and with thermal control's pumps and heaters on top the night load runs to about 31 kW, 34 kW at the night peak. There is no fourteen day night at this site: the best Shackleton rim locations see dark spells of a day and a half to about three days by model, and the 40 kWe fission unit is sized to carry that load through any of them, with margin for the terminator crossings and for the reactor to load follow rather than run flat out.

Section 08

Site plan

The four work areas and the graded routes between them, drawn to scale from the same metre coordinates the virtual tour walks through.

Habitation core 8.0 m dia / 148 m³ Observation cupola 4.5 m / the one window Laboratory 5.0 m / curation Greenhouse bay 5.0 m / 22 m² grow EVA airlock 4.0 m / suit ports Landing and launch pad 22 m apron / 29 m blast berm Solar array 48 kW peak / vertical ISRU plant 1.8 kg O₂ per day Excavation face 14 kg/hr regolith 65 m N 0 50 m Regolith skirt and blast berm Graded and sintered route ISRU and excavation Power generation
The pad sits 65 metres out on a north east bearing because ejecta leaving a landing site in vacuum travels ballistically, and the berm has to stand between that and the hull. The excavation face is kept on the far side of the plant from the habitat, so haulage never crosses the living area.
References

Sources

Every figure in this document traces to one of these. Agency documents and peer reviewed work first, reporting only where it is the primary record.

[1]Burke et al., Internal layout of a lunar surface habitat, ASCEND 2022, NASA NTRS 20220013669 https://ntrs.nasa.gov/citations/20220013669Zoning and the net habitable volume method; the two crew, 127 m³ reference habitat with a 4.4 m metallic deck under a 6.5 m inflatable
[2]Mars Desert Research Station, The Mars Society https://en.wikipedia.org/wiki/Mars_Desert_Research_StationThe eight metre cylinder crews have lived in since 2001
[3]The Mars Society, India's first crewed Mars analog launches with Protoplanet, ISRO and The Mars Society, September 2025 marssociety.orgHOPE: the two module pattern, an eight metre crew module with a five metre utility module
[4]Whitmire et al., Minimum acceptable net habitable volume for long duration exploration missions, NASA Human Research Program, 2014 https://ntrs.nasa.gov/citations/2014001695125 m³ net habitable per person as the minimum
[5]NASA, Lunar living: NASA's Artemis Base Camp concept, October 2020 nasa.govThe surface habitat's place in the camp, and the rigid plus inflatable pattern
[6]Destiny laboratory module, Wikipedia https://en.wikipedia.org/wiki/Destiny_(ISS_module)106 m³ pressurised in a 4.3 m by 8.5 m cylinder at 14.5 t, the flown benchmark for mass per cubic metre