22 people are enough to build and sustain Martian colony

A new study led by George Mason University in Fairfax, Virginia, concluded that only 22 colonists were enough to build a Martian settlement. Previous estimates claimed a Mars colony would take 110 people to create and sustain. 

Human social and psychological behavior variables 

This yet-to-be-peer-reviewed study considered a variety of criteria for establishing a Martian colony, including human social and psychological behavior and the harsh landscape of the red planet. 

The researchers created a computational model of a Mars colony using Agent-Based Modeling (ABM), which is commonly used to analyze the interactions between people, objects, locations, and time.

They also looked at previous data on high-performing teams situated in remote, high-stress environments, including submarines, Arctic expeditions, war, and the International Space Station. 

The scientists used this model to simulate the human survival conditions on Mars, taking into account elements such as the interaction between individuals of varied skill levels, resilience, and stress. They also added four basic psychological personality traits: neurotic, reactive, sociable, and agreeable. Furthermore, the simulation included the Martian environmental variables that the future settlers would face. 

The computer simulation was carried out for 28 Earth days, with different numbers in each group ranging from 10 to 170 persons. 

“We found that an initial population of 22 was the minimum required to maintain a viable colony size over the long run. We also found that the agreeable personality type was the one more likely to survive,” noted the study, which has been uploaded on a pre-print server. 

While people with a neurotic personality are likely to die at a much higher rate compared to the other traits.

The study can be found in the pre-print server arXiv.

Study abstract:

Establishing a human settlement on Mars is an incredibly complex engineering problem. The inhospitable nature of the Martian environment requires any habitat to be largely self-sustaining. Beyond mining a few basic minerals and water, the colonizers will be dependent on Earth resupply and replenishment of necessities via technological means, i.e., splitting Martian water into oxygen for breathing and hydrogen for fuel. Beyond the technical and engineering challenges, future colonists will also face psychological and human behavior challenges. Our goal is to better understand the behavioral and psychological interactions of future Martian colonists through an Agent-Based Modeling (ABM simulation) approach. We seek to identify areas of consideration for planning a colony as well as propose a minimum initial population size required to create a stable colony. Accounting for engineering and technological limitations, we draw on research regarding high performing teams in isolated and high stress environments (ex: submarines, Arctic exploration, ISS, war) to include the 4 basic personality types within the ABM. Interactions between agents with different psychological profiles are modeled at the individual level, while global events such as accidents or delays in Earth resupply affect the colony as a whole. From our multiple simulations and scenarios (up to 28 Earth years), we found that an initial population of 22 was the minimum required to maintain a viable colony size over the long run. We also found that the agreeable personality type was the one more likely to survive. We find, contrary to other literature, that the minimum number of people with all personality types that can lead to a sustainable settlement is in the tens and not hundreds.