'Project Hail Mary' Sparks Questions About Surviving Interstellar Space Travel

United States - Ekhbary News Agency

'Project Hail Mary': How Can Humanity Survive Interstellar Space Travel?

Andy Weir's captivating science fiction novel, 'Project Hail Mary,' recently adapted into a blockbuster film, has ignited public imagination and scientific curiosity about the feasibility of long-duration interstellar journeys. Central to the narrative's intrigue is the fate of its fictional crew, specifically the question of why two of the three astronauts perished during their voyage across the vastness of space. This fictional dilemma serves as a compelling springboard for examining the real-world biological and technological challenges inherent in venturing beyond our solar system.

Dr. Haig Aintablian, an emergency physician and flight surgeon who leads UCLA's space medicine program, suggests that the method Weir employed to keep his crew alive—a four-year medically induced coma—might be precisely where the peril lies. While the concept of entering a state of suspended animation, sleeping shortly after launch and awakening upon arrival, sounds appealing, Aintablian cautions, "I don't think keeping the human alive and in a comatose state is necessarily the best option." The human body, he explains, is not designed for prolonged stasis. Astronauts in induced comas face significant health risks, including potentially fatal blood clots and severe muscle atrophy due to inactivity. Furthermore, the medical equipment and tubes required to sustain a comatose individual introduce additional risks of infection, complicating the already perilous nature of deep space travel.

These inherent dangers in prolonged medical stasis naturally lead to exploring alternative methods for crew survival on missions spanning years or even decades. Aintablian proposes cryopreservation as a potential solution: "When the day comes where you could freeze someone and just thaw them, you would have solved the issue." However, the widespread application of human cryopreservation for space travel faces substantial scientific and technological hurdles. The physiological resilience of the human body to the stresses of freezing and thawing, akin to how certain animals like wood frogs survive extreme conditions, remains largely unknown. Integrative biologist Matthew Regan from the University of Montreal points out that human hearts struggle to function below approximately 28 degrees Celsius. While some individuals have survived temporary, deeper drops in body temperature, these instances are far from the years required for interstellar transit, making complete cryopreservation a distant prospect.

Another avenue explored is the concept of hibernation. Regan draws parallels with small hibernating mammals, such as arctic ground squirrels, which can lower their body temperature below freezing during torpor, reducing their metabolic rate to a mere 2% of normal levels. Even hibernating bears significantly reduce their metabolic activity, lowering their body temperature by only a few degrees. Crucially, torpid animals do not suffer from blood clots or muscle atrophy, unlike humans confined to bed rest. If humans could achieve even a slight reduction in metabolic rate, similar to bears, space voyages could become more resource-efficient, requiring less sustenance and life support for the crew. Furthermore, torpor might offer a degree of protection against ionizing radiation, a major concern for spacefarers.

However, complete hibernation for the entire journey might not be feasible. Ground squirrels and other hibernators periodically rouse themselves, rewarming their bodies and moving around. Neurochemist Kelly Drew of the University of Alaska Fairbanks suggests this cyclical awakening may be vital for muscle regeneration and maintaining brain health. Similarly, humans might need periodic awakenings to keep their cognitive functions sharp, muscles strong, and possibly to consume nutrition. Hibernation biologist Hannah Carey of the University of Wisconsin-Madison highlights another consideration: the potential health risks of pre-mission weight gain. Bears that accumulate significant body fat before hibernation experience high cholesterol levels, which normalize as they lose weight. For humans, however, this side effect could elevate the risk of heart disease. Carey also notes that some captive ground squirrels in her lab experienced unexplained deaths during hibernation, suggesting their hearts might have been unable to cope with the strain, even with ample body fat.

Ultimately, the question of why the astronauts in 'Project Hail Mary' died returns to the author's intent. Weir himself clarified to Science News that their demise was not a biological failure but a "tech failure." He explained, "Being in a coma for four years is a dangerous proposition in the best of times. So a small tech failure can lead to catastrophic results. Which it did in this case." This distinction underscores that while biological limitations are significant, the reliability of technology is paramount for the success of ambitious space missions.

As interstellar travel remains a distant aspiration, fictional narratives like 'Project Hail Mary' serve a vital purpose. They not only entertain but also illuminate the profound scientific and engineering challenges that humanity must overcome. By examining the fictional scenarios and consulting with real-world experts, we gain a clearer understanding of the biological and technological frontiers that need to be conquered to make journeys to distant stars a reality.

Ekhbary News Agency