From underworlds to outerworlds

Nathan Smith gets to the bottom of how we might reach what’s way above…

02 September 2019

The term ‘underworld’ usually subsumes a negative meaning. Various definitions point towards the morbid and illicit nature of these lower regions. In ancient mythology, Hades was the god of the underworld, whose name eventually came to describe the home of the dead. Fast-forward several millennia and underworlds are now most commonly attributed to the social spheres in which criminal organisations go about their daily business. However, beyond these culturally and socially-defined hierarchies, there are many people actually living and working in literal and geographical underworlds. The study of these people will pave the way for humankind’s most daring voyage yet: an expedition into the ‘outerworld’. The goal? To stand on the surface of Mars and accelerate our transition to becoming a truly spacefaring interplanetary species.

Long duration space travel
Long duration interplanetary space exploration poses a number of risks to human physical and psychological health. It’s an inherently dangerous endeavour. But alongside that, issues related to prolonged confinement, lack of personal space and privacy, delayed communication, separation from friends and family, and monotonous work and living conditions can all contribute to impaired performance and experiences of ill health.

In the depths of space, long away from the safety and relative tranquillity of planet Earth, this breakdown in function can have severe and potentially deadly consequences. Thankfully, safety, performance and health risks may be mitigated via a number of processes. These range from selection and training to sympathetic human-centred design and the development and application of effective stress countermeasures (Sgobba et al., 2018). When implemented successfully, such processes should enable crew members not only to withstand the demands of a long duration space mission, but actually thrive and experience the journey as the life-changing and affirming experience it should be.

To better understand the risks to crew members and how to support their wellbeing and optimal function during a long interplanetary voyage, requires the study of people in comparable conditions. These comparators are often referred to as analogues. Although not directly replicating the demands of an interplanetary expedition (it is very hard to simulate microgravity), analogue settings do provide an ecologically valid context for collecting physiological and psychological data on topics ranging from sleep and immune function to teamworking and conflict resolution (Sandal et al., 2018; Suedfeld, 2018). Analogues also offer a platform for testing and developing skills. A range of underworld analogues have been identified and used for these purposes. Literal underworlds include those found beneath the Earth’s surface. This includes subterranean caves, deep-sea saturation chambers and submarines. Geographical underworlds are found at the bottom of the world in Antarctica, where fieldworkers spend long durations living and working in isolated micro-societies, sometimes under conditions of extended confinement.

Subterranean caves are one of the most interesting underworld analogue settings. Unlike the growing number of highly controlled space simulation experiments, these hinterlands offer a very real, physically demanding and potentially dangerous context for studying human behaviour: and compared to simulations, an experience that more closely resembles what it might be like to voyage into the cosmos. A 2018 article by Nicolette Mogilever and colleagues makes a compelling case for using caves to advance psychological and neuroscientific spaceflight research. The authors highlight many overlaps between the challenges faced in caves and those encountered in space: including isolation and confinement, high levels of risk, reliance on protective equipment for safety, information uncertainty, unusual lighting and sensory conditions, limited communications, and supply and escape difficulties.

By the early 1960s, scientists had already recognised the value of conducting research in caves. Most notably, between 1962 and 1972 the French geologist Michel Siffre conducted numerous cave experiments – in the process isolating himself and others in darkness for periods of up to six months. Siffre identified that living in these dark underworlds resulted in significant perturbations to a person’s sense of time and, at that point, provided ground-breaking new insights into human sleep/wake cycles. Interestingly, this work captured the attention of the newly established National Aeronautics and Space Administration (NASA), who contributed analytical expertise and funding to Siffre’s endeavours.

Despite offering a unique natural laboratory for spaceflight research, and being of keen interest to space agencies, psychologists have rarely used caves as a context for study. An exception is the recently published work by MacNeil and Brcic (2017), who systematically analysed the diaries of cave explorers to understand the coping strategies used to counteract stress in these trying and toilsome settings. Consistent with many other extreme populations, MacNeil and Brcic noted that cavers tended to rely on problem-focused coping approaches, such as planful problem-solving, putting in more effort and seeking support. Emotion-focused strategies, such as positive reappraisal, were suggested as a method for securing salutogenic stress reactions; used by cavers to identify the enjoyable and rewarding aspects of what is, from an objective point of view, a fairly torrid experience.  

Despite receiving relatively limited academic interest, caves are currently used for practical purposes and as a context for astronaut training. Since 2008, the European Space Agency (ESA) has used a cave system in Sardinia for their Cooperative Adventure for Valuing and Exercising human behavior and performance Skills (CAVES) programme. During a 6-day expedition, astronauts-in-training, or ‘cavenauts’ as they are sometimes known, live and work in a deep cave system to learn and practice a range of skills that map on to the International Space Station Human Behaviour and Performance Competency Model (Bessone et al., 2008). This includes skills related to teamworking, group living, cross-cultural awareness and decision-making. Ultimately, the purpose of this training is to equip astronauts with the competencies to live and work effectively in a small interdependent team in the restricted confines of space.

There is an underworld that has benefited from sustained research interest, and regularly been used as a spaceflight analogue. Antarctica is the coldest, windiest, driest and highest continent on Earth. It has regularly been suggested that living in Antarctica is as close to inhabiting another planet as you can get without actually leaving Earth. A collection of early findings and observations on the psychology of living and working in Antarctica are presented in the seminal textbook, ‘From Antarctica to Outer Space: Life in Isolation and Confinement’ (Harrison et al., 1991), and psychologist Ron Roberts reviewed ‘Psychology at the end of the world’ in The Psychologist in January 2011.

Today, probably the most well-known space analogue in the Antarctic underworld is the French-Italian research station Concordia. Concordia is extreme. It is approximately 1100 miles from the coastline, sits on Dome C above 3000m of altitude, and has an average external air temperature of around -50 degrees Celsius. During the dark winter period, station personnel are truly cut off and, for several months, evacuation is almost impossible in the event of an emergency. Crewmembers stationed at Concordia have aptly named it ‘White Mars’. Each year, ESA support research activities at Concordia and station personnel contribute to projects across a whole range of human science disciplines.

There are many studies on the psychological and social dynamics that take place in Antarctica (Palinkas, 2003; Palinkas & Suedfeld, 2008). We will explore two recent examples of research conducted at Concordia. In 2015, Michel Nicolas and colleagues examined the affective, social and cognitive outcomes of a winterover season. Their findings suggest that over the course of 12 months crew members perceived the confinement to be gradually more stressful, and in particular found the social dimensions to be increasingly difficult. In their study, perceived control was positively related to mature defence mechanisms, stress-recovery, and feelings of success and wellbeing. Such factors are highly relevant to long duration space missions.

Acknowledging that Antarctic confinement can be stressful – particularly during the mid-winter period – Sandal and colleagues (2018) examined the changes in coping strategy use, sleep and affect during an Antarctic winter season. Conducting monthly assessment on two separate Concordia crews, the researchers observed only slight decreases in sleep quality and positive affect, but no changes in negative affect towards the dark Antarctic midwinter. However, the changes in coping strategy use were striking. On average, all coping strategies – including both problem-focused and emotion-focused techniques – decreased towards the middle of winter and then rebounded as the light returned. This reduced effort to cope was interpreted as a psychological hibernation response, which served to protect resources during conditions of uncontrollable chronic demand. Prior studies in Antarctica (Barbarito et al., 2001) and anecdotes from Concordia crewmembers (such as the European Space Agency’s Research Doctor Beth Healey: see support this interpretation. The extent to which this hibernating response might be facilitative remains to be tested. Being able to actively induce a state that helps people maintain their resources, pass the time and withstand chronic stress would almost certainly be beneficial for an interplanetary voyage and the long trip to Mars.    

From underworlds to outerworlds
Planning for a return to the Moon, and beyond, ESA, NASA and other international space agencies have developed research roadmaps to de-risk the human side of future long missions. Recent evidence from confinement studies, and serious dysfunctional behaviour observed after a long deployment in Antarctica, suggest that we still have a lot to learn before we can safely send people off on long duration space exploration missions. Nevertheless, knowledge gained from our current efforts in the underworld will help us make progress, tackle these risks, and, one day, enable our species on its next great adventure, into the outerworlds and further into the unknown.

Dr Nathan Smith is a Research Associate at the University of Manchester
[email protected]

This article is part of the 'Under…' special.


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