They ran the model five times for 28 Earth years, and increased the population by 10 people each time - from 10 to 170 individuals.
“Given that there are four critical tasks that are needed continuously (air, water, food production and waste removal) in addition to handling disasters, and two skills needed for each task, we chose a population size of 10 as the minimum needed for a ‘stable’ colony size.
“The population is allowed to dip below 10 as long as it bounces back within 1.5 years, or the amount of time between Earth resupply shuttles.”
The test found all initial population sizes over 50 were able to sustain a population of at least 10 people across the time period, and that the bare minimum number to meet that criteria is at least 22 people.
And the Virginia researchers didn’t stop there, either, as they also took a look at the personality types best placed to handle the highly stressful environment that is living on a completely different planet.
“agreeables”: low competitiveness and aggressiveness, and not fixated on “stringent routine
“socials”: medium competitiveness, extroverted, require social interaction but not fixated on stringent routines
“reactives”: medium competitiveness and fixed on stringent routines
“neurotics”: high competitiveness, highly aggressive and a “challenged ability to adapt to boredom or a change in routine”
Perhaps unsurprisingly, the “agreeables” came out on top.
The researchers added: “In all runs, the Agreeable personality type was the only one to survive the full duration of model runs. This is likely because it has the highest coping capability.”
Their results found that while the “neurotic” was “most likely to fail”, and both “reactives” and “socials” fluctuated, the “agreeables” was the “most resilient”.
“While this model assigns equal numbers of each personality type, future work could try adjusting the proportion of each to possibly lead to a lower required minimum initial population. For example, a crew of all Agreeable personalities may be more successful,” they suggest.
Musk, meanwhile, said earlier this year that he was optimistic humans landing on Mars was "possible" in the next five years, and "highly likely" in a decade.