New Mars Forums

1. Geometry and intent
Bay span (joist direction): 5 m

Story height: 2.5 m from ground floor to underside of ceiling above

Use: People, furniture, light lab/office loads

Environment: Inside buried, pressurized dome; floor is not a pressure boundary

Support: Columns down to ground slab

Think of this as the Mars analog of your 2×10 joist bay.

2. Structural grid and columns
Grid (example):

Joist span: 5 m

Joist spacing: 0.4–0.6 m (similar to 16–24 in o.c.)

Primary beams: Running perpendicular to joists, say every 4–5 m

Columns: At beam intersections, down to ground slab

So one “module” might be:

Plan: 5 m (joist span) × 4 m (beam span)

Columns: At the four corners of that rectangle

Columns:

Material: Light steel (e.g., square hollow sections)

Depth: 100–150 mm square is plenty for these loads and heights

Base: Bolted to plates anchored into the ground slab

3. Mars “2×10 equivalent” joist
We want something that feels like a 2×10:

Span: 5 m (shorter than your 6.1 m house span → easier structurally)

Target depth: ~200–250 mm

Option A: Steel I-joist

Section depth: ~200–220 mm

Flange width: ~80–120 mm

Spacing: 0.4–0.6 m

Support:

Ends sit on primary beams or ledgers welded/bolted to columns

Option B: Cold-formed steel joist

Depth: 200–250 mm C-section

Spacing: 0.4–0.6 m

Advantage: Light, easy to ship, easy to cut and screw together

Either way, visually and functionally, this is very close to a 2×10 wood joist system.

4. Deck and floor build-up
On top of the joists:

Deck:

Option 1: Structural panels

18–25 mm structural panel (plywood, OSB, or composite sandwich panel)

Screwed to joists

Option 2: Thin metal deck + topping

0.8–1.0 mm corrugated steel deck

30–50 mm regolith-concrete or lightweight topping for stiffness and acoustic mass

Finish layers:

Underlayment: 5–10 mm (if needed)

Floor finish: 5–10 mm (vinyl, laminate, tile, etc.)

Total floor depth (joist zone):

Joist: 200–250 mm

Deck + finish: 30–60 mm

Total: ~230–310 mm

That’s right in the same ballpark as your house floor.

5. Vertical section from ground to second floor
From bottom to top:

Compacted regolith subgrade

Ground slab:

100–150 mm stabilized regolith/concrete

Column base plates:

10–20 mm steel plates anchored into slab

Columns:

100–150 mm square steel tubes, 2.5 m tall

Primary beams:

Steel I-beams or box beams at column tops, spanning 4–5 m

Joists:

200–250 mm deep steel/CF joists spanning 5 m between beams

Deck:

18–25 mm panels or thin metal deck + 30–50 mm topping

Finish floor:

5–10 mm

Story height:

Clear height below joists: ~2.2–2.3 m (if you leave joists exposed)

Or you can add a ceiling (e.g., 50–100 mm drop) for services, still staying within 2.5 m story.

6. Why this works well for Mars
Span is modest (5 m): So we can keep joists shallow, like 2×10 analogs.

Dome + regolith handle pressure: So this floor is just gravity + comfort, not a pressure plate.

Columns to ground: Give you a clear, simple load path—no heroic long-span beams.

Materials: Steel/CF joists and panels are shippable, modular, and easy to assemble in a pressurized interior.

If you want, next step we can:

Lay out a full grid for, say, a 20 m × 20 m interior using these 5 m × 4 m bays,

And show how the second floor walks around airlocks, trunks, and greenhouse interfaces.

Mars has no slab, concrete but we might use steel or other materials that act like it with heated bonding
See my thinking
You’re right to call that out—if we throw out “slab and concrete” as defaults, the logic shifts, but the bay concept still holds. Let’s rebuild it with no wet concrete, just steel and bonded/composite elements.

1. Ground interface without a concrete slab
Think of the “slab” as a steel foundation grillage sitting on compacted regolith.

Subgrade:

Compacted regolith, leveled and densified where columns and heavy items sit.

Steel bearing pads / sleepers:

Option A: Individual steel base plates (say 400–600 mm square, 20–30 mm thick) under each column.

Option B: Steel sleepers (I-beams or channels) laid on the regolith, forming a grid that spreads loads.

Anchorage:

Columns are welded/bolted to these plates/sleepers.

If you want more “bite” into the ground, you can add short ground anchors or driven posts, but you don’t need a monolithic slab.

So instead of “slab + column,” you have “compacted regolith + steel pad + column.”

2. Columns and primary frame
We keep the same geometry:

Story height: 2.5 m

Bay: 5 m span (joist direction) × ~4–5 m (beam direction)

Columns:

Steel square tubes, ~100–150 mm, 2.5 m tall.

Base welded/bolted to steel pads or sleepers on the regolith.

Primary beams:

Steel I-beams or box beams spanning 4–5 m between columns.

These carry the joists.

3. Mars “2×10 equivalent” without concrete
Now the floor itself:

Joists:

Material: Steel I-joists or cold-formed C-sections.

Depth: ~200–250 mm (your “2×10 analog”).

Span: 5 m.

Spacing: 0.4–0.6 m.

Deck (no concrete):

Option 1: Structural sandwich panels

Aluminum or steel skins with a lightweight core (foam, honeycomb, or bonded regolith–polymer mix).

Thickness: 40–80 mm.

Panels span between joists and are screwed/bolted down.

Option 2: Metal deck + bonded infill

Thin corrugated steel deck.

Cavities filled with heated-bonded regolith–polymer or other composite (no wet cement).

Top skin (sheet or panel) bonded on, forming a closed cassette.

In both cases, you’re using heated bonding (thermoplastics, resins, or sintered/bonded regolith) to create stiff, light panels that act like a slab.

Finish:

Thin underlayment + floor finish (5–10 mm).

Total floor depth:

Joist: 200–250 mm

Panel: 40–80 mm

Finish: 5–10 mm

Total: ~250–340 mm

Very similar to your house floor thickness, just with different guts.

4. Section from regolith to finished floor (no concrete)
From bottom to top:

Compacted regolith (locally densified under supports).

Steel base pads or sleepers on regolith.

Steel columns (100–150 mm square, 2.5 m tall).

Primary beams at column tops, spanning 4–5 m.

Steel joists (200–250 mm deep) spanning 5 m between beams.

Bonded composite deck:

Sandwich panels or metal deck + bonded infill.

Floor finish (thin).

No concrete, no monolithic slab—just steel + bonded composites sitting on compacted regolith.

5. Why this still works structurally
The dome + regolith handle pressure and shielding.

The steel frame handles gravity loads and stiffness.

The bonded panels give you a solid walking surface and diaphragm action without wet concrete.

The regolith is just a bearing medium, like soil under a steel-framed building with isolated footings.

If you want, next step we can define one specific panel type (dimensions, layers, and a regolith–polymer core) so this bay becomes a repeatable “kit part” for your whole habitat.

it appears that the attack angle is greater than 7' but less than 15' from the colored based line nose up from level.

Starship Belly‑Flop Nose‑Up Angle (for Drag & Heatshield Calculations)

1. Effective Angle of Attack
During the belly‑flop, Starship flies essentially broadside to the flow.
For drag‑equation and heating‑flux work, you can treat the vehicle as having:

• Angle of attack ≈ 90° (velocity vector nearly perpendicular to the vehicle’s longitudinal axis)
• Actual trim offset: ~10–15° nose‑up from perfect 90° to generate lift and control cross‑range
• For first‑order drag/heating calculations, the difference between 90° and 75–105° is small

2. Drag Equation Inputs
Use the standard form:

D = 0.5 · ρ · V² · C_D(α) · A

Recommended approximations for Starship belly‑flop:

• Projected area A: use the windward heatshield planform
• Drag coefficient C_D: 1.5–2.0 (typical for a broadside, high‑AoA blunt body)
• Angle α: 90° for projected area and Cd selection

3. Heatshield Temperature Modeling
The drag equation alone cannot give temperature.
Use a blunt‑body heating correlation such as Sutton–Graves:

q̇ ∝ ( √ρ · V³ ) / √R_n

Where:

• R_n = effective nose/leading‑edge radius
• During belly‑flop, the heatshield is effectively normal to the flow, so use α ≈ 90°
• The small trim angle mainly shifts the peak‑heating location, not the magnitude

4. Practical Summary
For engineering‑level approximations:

• Treat Starship as a flat, broadside plate to the flow
• Use α = 90°
• Use C_D ≈ 1.5–2.0
• Use Sutton–Graves (or equivalent) for heating, not the drag equation alone

If you want, give me the altitude and velocity band you’re analyzing and I’ll compute q̇ and an approximate equilibrium heatshield temperature.

How mass (dry mass + 100 t landing prop) ties into drag & heatshield heating

The drag equation itself:

D = 0.5 · ρ · V² · C_D · A

does not contain mass. Mass enters the problem through acceleration and the trajectory, via the ballistic coefficient.

1. Ballistic coefficient is the key link

Define the ballistic coefficient:

β = m / (C_D · A)

Where:
• m = vehicle mass (dry mass + landing prop + payload, etc.)
• C_D = drag coefficient
• A = reference area (for belly‑flop, the broadside heatshield/belly area)

Now write the deceleration:

a = D / m = (0.5 · ρ · V² · C_D · A) / m

Substitute β:

a = 0.5 · ρ · V² / β

So:
• Higher mass → higher β → lower deceleration for the same ρ and V
• That means the vehicle penetrates deeper into the atmosphere before slowing down.

2. What your “dry mass + 100 t fuel” does

Let’s say (example numbers):
• Dry mass ≈ 120 t
• Landing propellant ≈ 100 t
→ Total m ≈ 220 t = 220,000 kg

Assume (for order‑of‑magnitude):
• C_D ≈ 1.7 (broadside, high‑AoA blunt body)
• A ≈ 450 m² (about 9 m × 50 m side/belly area)

Then:

β ≈ 220,000 / (1.7 · 450) ≈ 220,000 / 765 ≈ 290 kg/m²

If you changed the mass (e.g., less landing propellant), β changes proportionally:
• More mass → larger β → less decel per unit dynamic pressure
• Less mass → smaller β → more decel higher up

3. How that feeds into heating and heatshield temperature

Convective heating (e.g. Sutton–Graves style) scales roughly like:

q̇ ∝ √ρ · V³ / √R_n

But ρ and V as functions of time/altitude depend on β:

• High β (heavier ship):
– Slows down later and deeper in the atmosphere
– Encounters higher densities at higher speeds
– Higher peak heating and higher peak g‑loads, but over a shorter time

• Low β (lighter ship):
– Slows down earlier, at lower densities
– Lower peak heating and lower peak g‑loads, but over a longer time

The equilibrium heatshield temperature at a given point is set by:

q̇_in (convective + radiative) ≈ q̇_out (radiation + conduction into structure)

Since q̇_in depends on ρ and V, and those depend on β, your dry mass + 100 t landing prop directly affects:
• The altitude where peak q̇ occurs
• The magnitude of peak q̇
• The time history of heating (integrated heat load)

4. Practical takeaway

• The drag equation gives you force.
• Dividing by mass gives you deceleration, which introduces the ballistic coefficient β.
• Your chosen mass (dry + 100 t prop) sets β, which sets the reentry profile, which in turn sets the heating environment and thus the required heatshield performance.

Color changes on heatshield tiles can act as a rough “temperature history” indicator, but only in a qualitative way.
The visible oxidation state of a ceramic or metallic tile surface reflects the maximum temperature it has reached, because different oxides form or change color at different thermal thresholds.

1. Why tile color correlates with temperature
The surface chemistry of a heatshield tile shifts as it is heated in an oxygen‑bearing environment.
Different temperature bands produce different oxide phases:

• Iron oxides — shift from grey → red/brown → black as FeO/Fe₂O₃/Fe₃O₄ ratios change
• Silica-based ceramics — develop white, cream, or light‑grey devitrification at high temperatures
• Boron or carbon additives — darken or lighten depending on oxidation rate
• Metallic fasteners or edges — show straw → bronze → blue → grey scaling (classic temper colors)

These color states “freeze in” once cooled, giving a record of the highest temperature the surface reached.

2. What this means for Starship-style tiles
Starship’s tiles are silica‑based with a black borosilicate coating.
The coating can show:

• Light grey patches — surface glass layer reflowed or ablated
• Brownish tint — partial oxidation of impurities or binder residues
• White speckling — micro‑cracking or devitrification from very high peak heating
• Matte vs glossy differences — indicates whether the glassy surface layer softened

These are not precise thermometers, but they do indicate whether a tile saw, for example, 800°C vs 1200°C vs 1500°C.

3. Limits of using color as a temperature gauge
Color is influenced by more than temperature:

• Local oxygen availability
• Heating duration
• Repeated cycles vs one‑time peak
• Surface contamination (dust, salts, soot)
• Micro‑abrasion from plasma flow or particulates

So color gives a qualitative “temperature band,” not a calibrated value.

4. How engineers actually determine heatshield temperature
Color is only a post‑flight clue. Real temperature data comes from:

• Embedded thermocouples
• Infrared imaging
• Ablation mass‑loss measurements
• CFD + trajectory reconstruction
• Radiative equilibrium modeling

Color is used mainly to identify “hot spots,” tile damage, or uneven heating patterns.

5. Practical interpretation
If a tile shows:

• Uniform dark black — normal heating, coating intact
• Brownish or reddish tint — moderate oxidation, mid‑range heating
• Grey/white patches — high‑temperature glass transition or devitrification
• Blue/metallic hues on metal parts — classic temper colors indicating 200–600°C ranges

This lets you map relative heating across the windward surface.

A question for you: Are you trying to estimate the peak temperature a specific tile design will see on Mars entry, Earth entry, or both?

The thought is to use starship cargo as the delivery of the mars cargo lander. That means using the payload of the the starship to build what we need. It lifts the rocket lander with no propellant to stay within cargo limits, Gets refueled at the same time as the starship cargo.

Hydro gels detract from the payload of the mars lander that we are trying to send as starship is not refueling with these.

Have put what I found here in The GW posting

Thanks to Void we have another to make use of in "Mars Direct 3 is a Mars mission architecture developed by Miguel Gurrea" topic.
https://www.marspapers.org/paper/Gurrea_2021.pdf

Plus Mars direct was a 40mT payload
https://www.marspapers.org/paper/Zubrin_1991.pdf

A reuseable craft requires the means to make the fuel of choice.

Here is the Marco polo topic first link for fuel manufacturing lander for mars.

https://kiss.caltech.edu/workshops/isru … anders.pdf

As KBD512 indicated "40t is not about colonization, it's about exploration with a crew of 4 people going on a conjunction class / "long-stay" mission."

The reason is safe landing of equipment for large rocket pad creation and preparation using tele robotic systems.

Have added GW's content to the Forty 40 Ton Mars Delivery Mechanism end of this topic.

It is the Connex box delivery system of the "Mars Expedition Number One; 17 crew members" we had proposed.

Have fed the topics conversation into copilot and here is the response

I found the original First laboratory on Mars; equipment and scientists.

Here is the

Here is the ends of the tanks which are ribbed

That explains why the 9m shell is is listed as the internal tank as 10cm smaller

Here is what it thinks is missing from the wiki but we may have discussed some of these in the conversation

You’ve built an extremely thorough first‑mission concept — but when you step back and look at it as a mission architecture, there are a few critical gaps that would prevent this plan from being executable as‑is. These aren’t criticisms; they’re the natural “missing pieces” that every early mission concept has before it becomes a full design reference architecture.

What follows is a structured breakdown of what’s missing, grouped by the categories that matter most for a real mission: mission architecture, systems engineering, crew operations, infrastructure, and risk management.

1. Mission Architecture Gaps
These are the highest‑level missing elements — the things NASA or SpaceX would require before approving a mission.

? Launch, Transit, and Staging Architecture
Your document describes the surface mission in great detail, but it does not yet specify:

How many Starships launch from Earth

How they refuel in LEO

Whether they travel as a convoy or independently

Abort modes during transit

Communications architecture during cruise

Radiation shielding strategy during transit

Crew rotation, sleep cycles, and medical monitoring during the 200‑day trip

Without this, the mission is missing the “Earth → Mars → Earth” connective tissue.

? Navigation, Entry, Descent, and Landing (EDL)
You assume Starship can land reliably, but the plan does not address:

Precision landing requirements (must land within ~100 m of pre‑landed assets)

Dust plume mitigation

Landing pad preparation for the first landing

Redundancy if one Starship crashes or tips over

How to avoid sandblasting pre‑landed equipment

This is a major missing piece because the entire mission depends on safe, repeatable EDL.

2. Systems Engineering Gaps
These are the “invisible” systems that make a base survivable.

? Life Support System (ECLSS) Architecture
You mention MOXIE, Sabatier, and electrolysis, but the plan lacks:

A complete closed‑loop ECLSS design

CO₂ scrubbing capacity and redundancy

Humidity control

Trace contaminant removal

Filter replacement schedules

Spare parts manifest

Failure modes and contingency operations

A 17‑person crew for 550 sols requires ISS‑level system detail.

? Power Budget and Distribution
You specify nuclear + solar, but the plan does not include:

Total kW required for:

Habitation

Heating

Lab equipment

Vehicle charging

ISRU

Greenhouse lighting

Power distribution layout

Cable routing

Load shedding priorities

Nighttime power strategy

Reactor shielding and maintenance plan

Without a power budget, the base cannot be sized correctly.

? Thermal Control
Mars is brutally cold. Missing elements include:

Heat rejection systems

Heat recovery from reactor and ISRU

Thermal insulation specs for pit houses

Freeze protection for pipes, tanks, and vehicles

3. Crew Operations Gaps
Your triad structure is strong, but several operational elements are missing.

? Daily Schedule and Workload Modeling
You propose a 6‑hour workday + 3–4 hours of construction, but the plan lacks:

EVA time budgeting

Airlock cycling constraints

Fatigue modeling

Psychological support

Crew rotation for night shifts

Emergency medical protocols

Crew time for maintenance of:

Suits

Vehicles

Lab equipment

Habs

Power systems

?✈️ Mission Control and Autonomy
Missing:

How much Earth‑based oversight is expected

What tasks must be autonomous due to 20‑minute delay

Onboard computing and AI support

Data storage and transmission bandwidth

4. Infrastructure and Construction Gaps
You describe pit houses and Quonset‑style structures, but several engineering details are missing.

? Structural Engineering
Missing:

Load‑bearing calculations for regolith overburden

Internal pressure vessel design

Airlock redundancy

Tunnel pressure ratings

Dust intrusion control

Fire suppression systems

Materials compatibility with Mars environment

? Heavy Equipment Logistics
You list Bobcats and rovers, but the plan lacks:

Fuel/energy requirements

Maintenance schedules

Spare parts inventory

Lubricant behavior in low pressure

Hydraulic system performance in cold temperatures

? Laboratory Safety and Contamination Control
Missing:

Biohazard containment

Cleanroom protocols

Sample sterilization

Cross‑contamination prevention between Earth life and Mars samples

NASA will not approve a life‑detection mission without this.

5. Risk Management Gaps
This is the biggest missing category.

☢ Radiation and Solar Storm Protocols
You mention regolith shielding, but not:

SPE (solar particle event) shelter design

Dosimetry monitoring

Crew exposure limits

Emergency sheltering procedures

? Emergency Response
Missing:

Fire response

Habitat depressurization response

Medical evacuation plan

Redundant comms

Redundant power

Redundant ISRU

Redundant water extraction

? “Loss of Starship” Scenarios
Your plan assumes:

All Starships land safely

All reactors work

All ISRU systems work

All vehicles work

A real mission must include:

What if the return vehicle is damaged?

What if ISRU fails to produce enough methane?

What if the reactor fails?

What if a dust storm lasts 60 days?

6. Scientific Gaps
Your science plan is strong, but missing:

Planetary protection protocols

Sample return architecture

In‑situ calibration standards

Geological mapping plan

Traverse planning for rovers

Data archiving and transmission

7. Logistics and Manifest Gaps
You mention food, water, and equipment, but the plan lacks:

Full mass budget

Volume budget

Center‑of‑gravity constraints for Starship

Stowage plan

Consumables tracking system

Spare parts manifest

Suit inventory and repair kits

8. Governance and Crew Dynamics
You describe leadership roles, but missing:

Conflict resolution protocols

Crew selection criteria

Psychological screening

Cultural/linguistic considerations

Privacy and personal space requirements

Recreation and morale systems

The Core Answer
What is missing?
A complete mission architecture: launch → transit → landing → base construction → operations → return.
A full systems engineering backbone: power, thermal, ECLSS, redundancy, risk management.
A detailed operational model: schedules, EVA planning, maintenance, autonomy.
A structural engineering package: load calculations, materials, safety systems.
A logistics and mass budget: manifests, spares, stowage, consumables.
A planetary protection and science operations plan.

Your concept is an excellent crew and task structure, but it needs the engineering, logistics, and risk framework that turns a concept into a mission.

Here is what it thinks is missing

Copilot analysis clean slate output

US military airlifts small reactor as Trump pushes to quickly deploy nuclear power