Scientists have calculated the minimum number of astronauts needed to build and maintain a Mars colony

Just about two dozen astronauts are enough to build and maintain a colony on Mars, according to a new study, suggesting that this low number — compared to a previous estimate of around 100 — could sustain a habitat on the Red Planet.

Researchers, including those from George Mason University in the US, reviewed previous studies, which calculated that between 100 and 500 astronauts might be needed to establish a self-sustaining Martian colony depending on a number of factors.

Their new analysis, which has yet to be peer-reviewed, was published in arXiv, and then also took into account human social and psychological behavior, as well as the continuity of interpersonal interactions, to make a new estimate.

The results suggest that just 22 people may be enough to build and maintain a space colony on Mars.

Decades of exploration of the Red Planet by space agencies around the world have concluded conclusively that building any human settlement on Mars would be an incredibly complex engineering problem.

Scientists say the Red Planet’s inhospitable nature also requires that any habitat built there be largely self-sustaining.

Aside from extracting some essential minerals and water, future Martian settlers will depend on resupplying the Earth as well as replenishing necessities on site using advanced technology such as splitting Martian water into breathing oxygen and hydrogen for fuel.

The researchers say that future colonists will also have to endure the challenges of psychological and human behavior.

In the new study, data scientists sought to better understand the behavioral and psychological interactions of future Martian colonists.

“We seek to identify areas that must be considered when planning a colony, as well as to suggest a minimum initial population size required to establish a stable colony,” they wrote in the study.

For the analysis, the scientists analyzed past data on high-performance teams operating in isolated, high-pressure environments such as submarines, Arctic exploration, and the International Space Station to model the types of interactions that occur between agents with four different psychological profiles.

They used a type of computer simulation called agent-based modeling (ABM) that is used to analyze complex systems and predict the emergence of larger patterns and phenomena with simple rules and behaviors.

Using the model, the researchers simulated the survival of a human habitat on Mars under various operating conditions, including when global events such as accidents or delays in Earth’s resupply affected the colony.

Scientists created models of Martian settlers with individual levels varying from factors such as metabolism, resilience, skill levels and levels, and stress, as well as taking into account one of four psychological traits – neurological, reactive, social, or agreeable.

The study indicated that the simulation also took into account environmental variables that settlers might encounter.

Since typical Martian colonists sleep, move around, interact with each other, and produce or consume resources, they may also lose health and may die and be ejected from the simulation without sufficient resources.

Five runs of the model for 28 years with initial population sizes in the simulation ranging from 10 to 170 found that “an initial population of 22 was the minimum required to maintain a viable colony size over the long term.”

The researchers also found that the “acceptable” personality type, which is associated with greater empathy in general, is the type most likely to survive while those with “neurotic” psychology die at a much higher rate.