Given a health-first ethics that currently favors large artificial-gravity orbitals over surface cities, what concrete empirical comparisons—across radiation exposure, partial-gravity countermeasures, psychosocial well-being, and long-run maintenance risk—are needed to decide when a high-closure Martian or lunar surface settlement with strong shielding and chartered non-domination safeguards is in fact ethically on par with, or superior to, an AG orbital habitat for multigenerational residence?

Answer

Needed are side‑by‑side, quantitatively comparable data on health and risk in AG orbitals vs. shielded Moon/Mars bases, focused on a few core outcome bundles.

1. Radiation exposure

• Direct compare: • Annual and lifetime effective dose for adults/children in: (a) well‑shielded AG orbital; (b) buried lunar base; (c) buried Martian base. • Organ‑specific doses (gonads, bone marrow, CNS).
• Key comparisons: • Dose vs. accepted Earth worker and public limits. • Residual excess cancer, infertility, and developmental‑defect risk.
• Threshold to treat surface as on par: • Surface designs show ≤ similar lifetime cancer and fertility risk as AG orbitals for same shielding mass and operations profile.

2. Gravity and countermeasures

• Direct compare: • Long‑run bone, muscle, cardiovascular, vestibular, pregnancy, and child‑growth outcomes in: – 1 g AG orbital. – 0.38 g Mars + countermeasures. – 0.16 g Moon + countermeasures (likely only to rule lunar cities out).
• Key comparisons: • Are deficits at 0.38 g with best feasible countermeasures small enough vs. 1 g AG to stay within accepted medical risk for children and pregnant people? • Are any impairments reversible after return to 1 g?
• Thresholds: • For Mars: no severe, irreversible harms to gestation/childhood vs. 1 g; adult morbidity within modest multiple of AG orbital. • For Moon: if harms remain large despite countermeasures, family‑scale cities stay ethically worse than AG orbitals.

3. Psychosocial well‑being

• Direct compare (matched crews/populations): • Rates of depression, anxiety, conflict, PTSD‑like symptoms. • Social cohesion, family stability, perceived autonomy. • Preference‑revealing data: retention/return rates when exit is available.
• Settings to compare: • Spacious AG orbital with simulated “neighborhoods”. • Subsurface Mars town with limited outdoor access but real gravity and landscape. • (Optionally) lunar base analog.
• Thresholds: • Surface settlements show equal or better long‑run mental health and social metrics than AG orbitals for similar density and work patterns.

4. Long‑run maintenance and failure risk

• Direct compare: • Mean time between critical failures (life support, structure, power). • Probability of unrecoverable event per decade per 10,000 residents (including evacuation feasibility). • Maintenance labor and spare‑parts burden per capita.
• Context: • Orbitals: higher debris and structural risk, easier evacuation. • Mars: less debris, harder evacuation, dust/thermal penalties.
• Thresholds: • After shielding and redundancy, Martian bases must show equal or lower per‑decade mortality risk than AG orbitals for residents, accounting for poorer evacuation options.

5. Integrated ethical comparison

• Build simple, shared metrics: • “Expected healthy life years lost per 10,000 residents per decade” from: radiation + gravity biology + accidents + psychosocial harms. • “Domination sensitivity index”: how badly outcomes worsen when charters or oversight degrade (using tools from 1a794618, 910d70d0).
• Conditions for surface parity or superiority: • Health bundle: surface ≤ AG orbital in expected life‑years lost and severe‑disability cases. • Risk bundle: no higher probability of catastrophic, unrescuable loss. • Governance: with similar non‑domination charters, surface sites are not more prone to sliding into structural dependency than orbitals, or they offer compensating goods (e.g., large psychosocial gains) that offset small health deficits.

6. Concrete empirical programs to get there

• Partial‑g biology: • Long‑term 0.38 g vs. 1 g AG experiments on mammals, then small human cohorts, including pregnancy and childhood development.
• Radiation + shielding: • In‑situ measurements in prototype buried lunar and Martian habitats vs. AG‑analog orbital modules with equivalent shielding mass.
• Psychosocial trials: • Multi‑year comparisons of groups in high‑fidelity AG‑analog vs. buried‑base analogs on/near Earth, tracking mental health, conflict, and retention under similar work and governance rules.
• Reliability modeling: • System‑level simulations and field tests of maintenance, failure modes, and evacuation options for both architectures at 10^3–10^4 population scale.

Once these comparisons show that a strongly shielded, high‑closure Martian (or lunar) settlement matches or beats AG orbitals on total health risk and doesn’t create greater structural domination or catastrophic‑failure exposure, a health‑first ethics could treat such surface settlements as ethically on par or, where psychosocial outcomes are clearly better, as superior for multigenerational residence.