Since the Space Race, there has been a culture-wide obsession with expanding our reach in the cosmos, and NASA is still on board: They are now thinking about getting mankind to Mars. It’s not a simple process, as scientists don’t just have to look at the technology behind space flight, but also the psychology and physiology involved in such a mission must be considered. Can the astronauts handle it?

On Wednesday, Mark J. Shelhamer of the Johns Hopkins University School of Medicine spoke about on how NASA hopes to protect “human health and performance on a mission to Mars,” as well as his own approach to the issue.

Shelhamer spent 2013 to 2016 as the chief scientist for human research at NASA, making him uniquely familiar with both the problems astronauts face and the work NASA is doing to solve them. NASA wants to send people to Mars in around 20 years, he said, and so in about 10 years, the Human Research Program will have to decide if they’ll be ready by then. 

At any given time, there are usually six astronauts at the International Space Station, each of whom fulfills a six-month shift. Currently, they’re still in “Earth Reliant Mode,” said Shelhamer, explaining that if there’s a problem, they can talk to mission control instantly or return to Earth in a matter of hours. 

Meanwhile, Mars is 30 million miles away, and there will be a communication lag of at least 20 minutes with Earth. The HRP’s aim right now, according to Shelhamer, is to give the crew the tools to operate in “Earth Autonomous Mode.” To do this, NASA is looking into the problems that astronauts may face in space and how they can handle each of them.

Shelhamer explained that some obstacles, such as bone and muscle problems, due to altered gravity, are predictable. However, NASA doesn’t yet know every problem the astronauts will face. 

Most studies have been short-term, and it will take three years to get to Mars and back. Short-term studies can’t predict long-term effects, Shelhamer said, sharing an example of astronauts developing visual impairment after six months on the International Space Station. Two-week tests didn’t indicate that that might happen, he said. 

Just as concerning are the psychological effects of a long-term mission, which haven’t been tested. The crew will spend three years working, interacting and living with a very small group of people. They’ll be dealing with a hostile environment and experiencing isolation from their homes. In studies of astronauts on the ISS, their stress levels have continually gone up throughout their stay. Shelhamer said algorithms indicate that these levels would keep rising. 

To handle these problems, NASA uses a chart called the “Integrated Path to Risk Reduction.” The chart lists the problems astronauts may face and their risk factors by how likely each problem is to occur and how bad its effect will be.

 Shelhamer pointed to unpredictable effects, like radiation, highlighted in gray, while high-risk effects like “Inadequate Nutrition” and “Cognitive or Behavioral Conditions” are in red. Solved ones, such as “Reduced Aerobic Capacity,” are in blue.

However, the chart is “kind of crap,” Shelhamer admitted, because it works as though every problem is completely independent from every other. Shelhamer would rather NASA implement an integrated approach which captures the interactions between one problem and another: for example, how high carbon dioxide levels will lead to decreased bone density in the head, how fluid shifts headward will lead to increased pressure on the brain and how these combined effects will have a negative impact on vision and cognitive functioning. 

NASA is trapped by their focus on the IPRR when they should be looking beyond it, Shelhamer said. “Body parts will not travel on exploration missions,” he asserted, “whole humans will.” 

Shelhamer’s preferred approach applies the concept of a “Small World Network” to systems interactions. He explained that a SWN is a mathematical chart in which small clusters of nodes, or points, are connected by a few larger nodes to other small clusters. Any node can reach any other node through a series of small hops. 

Similarly, scientists at the University of Colorado-Boulder mapped space risk factors into a “Contributing Factor Map.” The CFM integrates psychological, technological and physiological problems into one chart. The chart demonstrates their impact on each other and the snowball effect failures can provide. Shelhamer sees it as “a system of systems.” 

Shelhamer thinks that the CFM should be mapped as a Small World Network. If formulated properly, one could use the SWN to display the dynamics of the group and define its resilience function or how stable the system is. The topology of the SWN shows where potential problems are, and the resilience function shows how close to catastrophe it is. 

If scientists can monitor where a group is on the resilience function, they can prevent problems from snowballing. 

Ideally, Shelhamer would have the system of each flight mission mapped as a SWN and have the commander use the map to detect warning signs. 

Shelhamer acknowledged that his approach isn’t perfect; crewmembers might not want their dynamic to be observed at this level, as it would feel invasive. 

However, he’s confident that NASA’s approach isn’t ideal either.