We don’t know exactly when, and we are not even sure how, but one day humans will travel to the Red Planet. The journey will not be easy. First, there is the incredible distance between the two planets. When Neil Armstrong, Buzz Aldrin, and Michael Collins flew to the moon in 1969, the odometer read approximately 500,000 miles for the round trip—a distance they covered in just eight days. For Mars, the distance will range anywhere from 70 to more than 100 million miles. Just flying there and back, with no landing on the surface, will take more than 500 days!
The sheer magnitude of the flight raises a number of issues. For example, how do you bring along enough water, oxygen, and food for the crew to survive? How do you protect the crew from the large amount of radiation in space or the debilitating effects of prolonged exposure to microgravity? Perhaps the most important question is: Who should be selected to make this incredible journey?
I have long been interested in how small teams of people work together in unique and challenging settings. With my background in human factors psychology, a scientific discipline focused on understanding interactions between humans and other elements of a system, I have studied teams in a number of contexts, such as military operations and sports. However my true passion is space, specifically long-duration space missions like those to the International Space Station (ISS) and Mars. One of the difficulties of research in this area is it’s hard to get access to the relatively small number of men and women who actually go into space each year. However, much can be learned about life in space through simulations here on Earth. For example, a group of my students from Embry-Riddle Aeronautical University recently spent two weeks at the Mars Desert Research Station. From a remote location in the Utah desert, this simulated Mars habitat offered an ideal setting in which to study how prolonged isolation and confinement affects behavioral factors such as crew cohesion—the degree to which members of a team are committed to each other and their shared tasks—and coping with the stress of living and working in close quarters.
It is from studies like this, and many others conducted in settings analogous to spaceflight, like Antarctic research bases, submarines, and underwater habitats, that scientists have begun to understand the qualities that would make up the ideal Mars-bound crew. Starting with the basics, we know that larger crews tend to function better than smaller ones. A crew of six or eight individuals provides more overlap in skill sets and can better share the workload of operating a complex space vehicle and conducting research than, say, a crew of two. In terms of the composition of the crew, evidence suggests a mixture of men and women offers many advantages for performance and interpersonal interactions over an all-male or all-female crew. Cultural diversity also has benefits to performance, although there have been some issues in previous space missions related to misunderstandings attributed to language differences and cultural norms.
Once we have established the size and mixture of the crew, the next question is: What traits should each woman or man possess? Generally speaking, you want someone who is a team player and works well with others, including the mission support personnel back on Earth. You also want people who know how to deal with disagreement and conflict in productive ways. As we have learned from other missions in space, and analogs on the ground, life in isolation and confinement disrupts sleep and can produce periods of high stress. These conditions, combined with the fact that there is no way to “leave” if someone gets on your nerves, means there will likely be moments when two or more people don’t get along. Working through these disagreements will be crucial to the overall success of the mission. Furthermore, you want people who can handle long periods away from family and friends on Earth and tolerate boredom. Yes, even though phases of the mission will be extremely busy and exciting, for many months, the crew will experience the same conditions, day after day, with very little to do but wait. Therefore, we need to find people who are content with very few changes in their surroundings and activities. Finally, I strongly believe that a sense of humor will go a long way in helping the crew maintain their psychological health. In my experience, laughter is one of the easiest, and best, ways to cope with stress.
When humans do make that first journey to the Red Planet, I am confident we will send the very best crew possible. They will know each other’s quirks and learn how to work around differences of opinion. They will support each other and have a shared vision, and shared commitment, to the goals of the mission. Most of all, they will work together as one.
Jason Kring is a professor of human factors & systems at Embry-Riddle Aeronautical University.