The Digester

Mars is not a backyard frontier but an environment that kills unprotected humans quickly; surviving requires sealed, shielded habitats, vast energy, and continuous support from Earth.

Any surface settlement would need to be hermetically sealed or buried because the open Martian environment is immediately lethal.
Terraforming Mars to a breathable atmosphere would likely take centuries to millennia and may be impossible due to insufficient greenhouse gases.
Mars has about 1% of Earths atmospheric pressure and an atmosphere dominated by carbon dioxide, so a single breath on the surface is fatal without protection.
The planet lacks a global magnetic field, exposing the surface to much higher levels of cosmic and solar radiation that require heavy shielding.
Martian regolith contains perchlorates that are toxic to humans, so agriculture will need treated soil or closed hydroponic and bioregenerative systems.
Mars gravity at about 38% of Earths may cause progressive bone and muscle loss and has unknown effects for long-term residents and children.
Living on Mars is technically possible in engineered habitats but would demand huge energy, redundancy, resupply, and would remain psychologically and logistically dependent on Earth

Can humans really live on Mars? What science fiction gets wrong

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