Space Colonization and Terraforming Mars

Radiation Protection

Solar flares and cosmic rays create a deadly environment in space. The Van Allen belts in Earth orbit make living above the Earth’s atmosphere challenging. Life must be protected by enough mass to absorb most incoming radiation. Magnetic or plasma radiation shields may be developed to address this challenge.

Passive mass shielding using slag from the processing of asteroids and lunar soil into oxygen, metals, and other materials can reduce radiation dosage. Massive bulk vessels like mobile spacecrafts are hard to maneuver and use less massive active shields. To overcome inertia, powerful thrusters could start or stop rotation or electric motors could spin two massive vessel sections in opposite directions and material for shields can remain stationary around a rotating interior.

Self-Replication

Space colonies could replicate exponentially thru space manufacturing while slashing costs and dependence on Earth. Medium range goals include acquiring science, engineering, entertainment information from Earth and periodic supply of light weight objects including genetic material, integrated circuits, and tools. Space colonies would be Earth’s first act of self-replication.

Psychology

Prolonged, lonely, and monotonous space journeys can cause cabin fever or psychotic breaks in astronauts. In a space environment, nearly every action is critical. Fatigue, lack of sleep, and work overload may impact an astronaut’s ability to perform.

Population Size

Anthropologist John H. Moore (2002) calculated a population of 150–180 could create a stable society in space for 2000 years or 60–80 generations. Just two women could use human embryos from Earth. An Earth-based sperm bank could start with a small base with negligible inbreeding. Franklin and Soule (1980) found a short-term population size of 50 could prevent troublesome inbreeding and a population of 500 would maintain genetic variability and prevent genetic drift. A 1% inbreeding rate in space is half that used by domestic breeders on Earth. A generation starship starting with 98 settlers could ultimately reach Proxima Centauri according to astrophysicists Frederic Marin and Camille Beluffi in the August 2017 edition of the Journal of the British Interplanetary Society.

Location

Advocates of space colonization disagree on location. Space colonies can be located on a planet, dwarf planet, natural satellite, or asteroid, or the orbit of any of these bodies. Space habitats can be created off these bodies in space. Most important for the biochemistry of life as we know it is liquid water because it powers our search for extraterrestrial life.