Simulations, extreme environments test people's mental fortitude for voyage to Red Planet
Tang Yau Hoong
No one has come closer to experiencing the enduring solitude and high-risk travel that would accompany a mission to Mars than the three astronauts who flew to the International Space Station on November 23, 2002.
Just nine weeks later, the space shuttle Columbia exploded. That led controllers to extend the Expedition 6 mission, as the trio’s endeavor was known, from four to five and a half months — about the time needed for a trip to Mars. On the journey back from the space station, a spacecraft malfunction caused a high-speed reentry to Earth’s atmosphere, approaching speeds that would be reached when nearing Mars. The Expedition 6 capsule bumped and rolled to a stop about 475 kilometers off course, in a remote part of West Asia. The crew was rescued five hours later.
As they waited, the astronauts pulled themselves out of their battered craft, set up two radio systems and performed other survival procedures — all with great difficulty. The men’s bodies had become accustomed to the lack of gravity in space, so their limbs felt like dead weights. Each head movement caused a wave of dizziness. Two crew members with experience readjusting to Earth conditions during previous missions to the space station staggered about slowly. Rookie space traveler Don Pettit crawled back and forth between the capsule and the crew’s new base camp.
It wasn’t easy, but Expedition 6 demonstrated that a space station crew could perform critical procedures in a situation similar to a Mars trip and landing, Pettit wrote in 2010 in the Journal of Cosmology.
He acknowledged, however, that a longer Mars voyage would bring novel emotional and social challenges.
Much is known about the psychology of participating in space missions that circle Earth at relatively close range or venture to the moon. Scientists are in the early stages, however, of understanding what it takes to hurtle through space for half a year and spend 18 months exploring the Red Planet before facing another five to six months getting home.
Although no date has been set for a Mars expedition, researchers who study humans in space are planning for an interplanetary voyage by 2050. If and when it happens, Mars astronauts will live in an artificial environment devoid of natural light, where sleep can easily be disrupted. Sending a message to Earth and receiving a reply will take close to 45 minutes. About a half dozen crew members will have only themselves for company. A couple hundred million miles out in space, they’ll be the first humans to see their home planet as nothing more than a speck of light in the heavens.
Studies of people working for weeks in a desolate Utah desert, for months in the darkness of Antarctic winters and for more than a year on a simulated space expedition in Russia provide some guidance for selecting and training individuals and crews capable of dealing with the unpredictable challenges of a Mars mission. Studies of space shuttle and International Space Station crews offer insights as well.
The heady days of the 1960s space program, when courageous, quick-thinking and fiercely independent test pilots displayed “the right stuff” to become astronauts, are long gone.
“Researchers don’t talk about astronauts having ‘the right stuff’ for long-term space missions,” says psychologist David Dinges of the University of Pennsylvania School of Medicine. An interplanetary journey calls for a different kind of right stuff — characteristics that make for strong teams, not individuals, he says. The goal for future missions is to develop crews that work well enough in unison to compensate for any difficulties that individuals might encounter in space.
Consider the biological shock of leaving Earth to live in an orbiting facility where a suited-up astronaut floats in the air. “Going into outer space is the most dramatic thing that can happen to your body other than being born,” says astronaut Thomas Marshburn, who completed a five-month stay on the International Space Station in May 2013.
He eventually adjusted to the microgravity caused by the space station’s free fall around Earth and slept well. When a hectic work schedule cut into his sleep time, he took five-minute naps while floating in his room.
Marshburn was lucky. Some astronauts just can’t get enough shut-eye during missions. “The space environment is user-unfriendly for sleep,” says flight surgeon Smith Johnston of NASA’s Johnson Space Center in Houston. On the space station, slumber can be disrupted by constant noise and activity, temperature fluctuations and an artificial atmosphere in which elevated carbon dioxide levels may cause dizziness and other symptoms. Add to that changes in the timing of work shifts when supply craft and new crews arrive. Microgravity can trigger back pain and fluid shifts that lead to pressure inside the skull and vision problems. No one knows why.
Physiologist Laura Barger of Harvard Medical School and her colleagues tracked 4,311 days of sleep among 85 astronauts during space shuttle or International Space Station missions. Flights occurred between July 2001 and July 2011. Participants wore devices on their wrists that measured movement and provided relatively accurate estimates of time spent asleep.
Crew members headed into space sleep-deprived and stayed that way until returning, the researchers reported in the September Lancet Neurology. Nightly sleep averaged 5.96 hours during roughly weeklong shuttle missions and 6.09 hours during space station stays that ran as long as six months. Shuttle and space station astronauts slept for comparably short amounts of time beginning about three months before spaceflight, at the start of preflight training.
On Earth, chronic sleep restriction of that magnitude causes attention and memory problems, Dinges says.
About three-quarters of shuttle and space station crew members in the study took sleep medications at some point during their missions. But the meds helped only a little: Astronauts gained an average of about 10 minutes of sleep per day on the shuttle and 35 minutes on the space station, no more than would be expected by chance, Barger says. These minor improvements are similar to experiences of people who take the same meds for insomnia on Earth.
Because sleeping pills work for some insomniacs, Johnston hopes to find out which astronauts might be biologically receptive to sleeping pills and choose the most effective drugs and doses for those individuals. Other NASA strategies to promote nighttime sleep include equipping workstations with blue lights, which suppress levels of the sleep hormone melatonin and raise alertness so that astronauts can work a full shift before retiring, and designing computer-delivered instruction in relaxation exercises and sleep-promoting routines.
Even with normal gravity, serious sleep problems were the norm for four out of six participants on a one-of-a-kind simulated Mars trip. Dubbed the Mars 500, the simulation was conducted in Moscow from June 2010 to November 2011.
Participants conducted scientific experiments and other projects for 520 days, under the direction of mission controllers. That’s enough time for an actual round-trip to Mars, with time for about five months of research on the Red Planet.
The crew wore movement-tracking devices, which indicated that four men developed sleep problems during the faux flight, even though it was quieter than an actual space trip and they didn’t have to deal with microgravity. One participant slept an average of only 6.54 hours nightly. Another shifted from a regular 24-hour pattern of sleeping and waking to a 25-hour cycle, which can disrupt slumber, memory and decision making (SN: 2/9/13, p. 8).
Although they were carefully screened before the study, men who became troubled sleepers during the mission developed a range of psychological and behavioral problems, a team led by Dinges’ Pennsylvania colleague Mathias Basner reported March 27 in PLOS ONE. One man became increasingly depressed, physically exhausted and mentally fatigued. He and another slumber-deprived crew member had the bulk of arguments and conflicts with mission control and onboard comrades.
Another man took frequent naps during the day that lengthened as the study wound down. Rather than arguing or fighting with others, he increasingly withdrew from the group and spoke only occasionally with just two of his colleagues.
Although Bishop did not participate in Mars 500, she has led studies of teams on two-week simulated Red Planet expeditions that take place at an isolated outpost in Utah known as the Mars Desert Research Station.
On this forbidding, Mars-like landscape, teams of about six researchers conduct a variety of experiments relevant to a stay on the Red Planet, such as how best to grow food inside a structure that recycles wastewater. Since 2002, teams have performed best when members identified closely with the whole group, talked frequently with each other and focused on completing tasks, Bishop says.
These crucial elements of effective teams appear to have gone missing during the Mars 500 simulation.
Intriguingly, two crew members on the 17-month Mars 500 mission slept fine the whole time and adjusted well to their confined environment. These men interacted frequently with their colleagues, except for the withdrawn individual.
The researchers have yet to look for psychological or biological factors that distinguished happy, well-rested participants from those who struggled mightily and slept little during Mars 500. “This is a serious scientific mystery,” Dinges says.
NASA psychologist Albert Holland knows it will be tough to assemble a team capable of carrying out a Mars mission without major hitches.
Holland has coordinated psychological services at the space agency for 27 years. His duties include developing personality tests for astronaut candidates and conducting psychological training of astronauts for extended spaceflights.
A year on the space station might be followed by a year conducting experiments in Antarctica, where winter consists of months of darkness. Crews might then have to survive for several months in a desolate region with only caves for cover.
In a lead-up to such ventures, a six-member team is conducting a simulation of life on a Mars space station in a large dome built on the side of Hawaii’s Mauna Loa volcano. The NASA-sponsored project began in October and will last at least eight months.
Unlike a reality TV show such as Survivor, where each participant vies to win a contest in an exotic locale by whatever means necessary, Mars mission candidates sent to harsh environments need to work selflessly for the good of their crews.
All astronauts must be able to make decisions quickly in life-or-death situations, but long spaceflights such as a Mars expedition or year-long stint on the International Space Station demand a level of teamwork and group morale not needed on trips of a week or two. Some issues are difficult to predict in advance, even after observing teams in action on Earth. On a Mars trip, where men and women will probably work together, according to Holland, sexual tensions could split a team apart.
Some evidence suggests that the presence of women makes various kinds of teams more effective, at least in the short run, Bishop says. But long-term studies of men and women crew members are lacking.
“The key is to find and develop people who can manage their relationships with team members, look beyond their own needs and work toward a higher goal,” Holland says.
One crucial characteristic of a good team member is adaptability, at least according to 26 veterans of six-month space station missions recently interviewed by Holland. Crew members will need to deal well with stressful situations, stay on an emotionally even keel when things go wrong and maintain work quality in the face of sleep loss.
Astronauts in Holland’s study also emphasized social and teamwork skills, divvying up responsibilities and taking charge when needed during onboard emergencies.
Team building can be further complicated in space missions that include astronauts from different nations, which will certainly be the case with a mission to Mars. Crew members from various parts of the world will need to overcome cultural differences quickly when placed in extreme Earth environments, says psychiatrist Nick Kanas of the University of California, San Francisco. Previous research on Russia’s Mir space station and on the International Space Station suggests, for instance, that stressed-out Russians experience a blend of fatigue and depression. When U.S. astronauts get upset, they are more likely to report a mix of anxiety and depression, Kanas reports in the October-November Acta Astronautica.
Some emotional troubles transcend culture, Bishop says. Anger, depression and confusion spread rapidly when team members form cliques, regardless of where they come from, according to studies of U.S. and European scientists working at isolated Antarctic research stations.
Confronted with the pressure of surviving with others for a long time in confined spaces in a dark landscape, individuals often keep their worries and insecurities to themselves, Bishop adds. Members of polar expeditions studied by medical anthropologist Lawrence Palinkas of the University of Southern California in Los Angeles often expressed concern about not burdening others, even after being injured. There’s good reason for such concern: Leaders of polar treks and months-long submarine missions have reported feeling overwhelmed and frustrated when asked for emotional support by teammates.
Aspiring Mars astronauts, as well as mission controllers for a Mars expedition, must be able to rely on each other. Space travelers and ground officials won’t be able to communicate instantly, as they do during International Space Station missions. It will take about 22 minutes for messages from a craft on or near Mars to reach Earth, and the same amount of time for a response to reach space travelers. Regular conversations with ground officials, a fixture for astronauts on the International Space Station, will be impossible. Mars astronauts will have unprecedented independence to deal with onboard problems and urgent decisions.
To ease feelings of isolation among even the best-adjusted deep-space astronauts — who will not be able to use computers to chat with family members, as is common on the International Space Station — NASA may turn to virtual families, Holland says. Researchers are in the early stages of developing headgear that will place crew members in virtual, 3-D re-creations of their family homes, where they will visit simulated versions of their spouses, children and other loved ones.
For all its psychological and social challenges, space travel has a transcendent upside. From the beginnings of national space programs more than 50 years ago, astronauts have described how their lives have changed for the better as a result of their otherworldly journeys.
So it went for U.S. astronaut Jerry Linenger, even after enduring an onboard fire, a near-collision with a resupply rocket and several system failures during four months on Mir in 1997. In his 2000 book Off the Planet, Linenger described returning home with increased self-confidence, greater appreciation of life’s pleasures and a newfound sense of Earth and its human inhabitants as a unified entity.
In a 2006 survey of 39 U.S. and Russian astronauts, Kanas and his colleagues found that all of them reported personal growth as a result of flying in space. In particular, participants said they better grasped Earth’s beauty.
Returned astronauts often report a heightened concern for the collective interests of people around the world, world peace and a God that exists beyond specific religions, says psychologist Peter Suedfeld of the University of British Columbia in Vancouver.
Suedfeld and his colleagues reported in 2012 in Acta Astronautica that 20 retired Russian astronauts described positive changes such as finding more direction in their lives following their spaceflights. So did 125 U.S. astronauts, whose memoirs were analyzed by Suedfeld’s team in 2010 in the Journal of Personality.
Not everyone comes back inspired. Edwin “Buzz” Aldrin, who in 1969 became the second person to walk on the moon, sank into depression, developed alcoholism and got divorced after that mission. Following a 2006 mission on the International Space Station, Lisa Nowak was arrested for attempting to kidnap a rival girlfriend of a fellow space station astronaut with whom she had been having an affair.
Astronauts can only guess at how a Mars trip would affect them. Thomas Marshburn recalls that he and his crew mates on the International Space Station felt comforted and inspired by the sight of Earth outside the craft’s windows. When Marshburn floated to the other side of his space home and peered out at the twinkling universe, a sense of insignificance and aloneness took over. As much as he wants to participate in an eventual Mars mission, Marshburn knows it would be tough to watch Earth shrink into one of many distant stars during an interplanetary journey.
That humbling experience might lead to spiritual growth in some space travelers and emotional turmoil in others.
“There will always be an element of the unknown and the unexpected on long spaceflights,” Holland says.
If there is such a thing as “the right stuff” for teams of astronauts journeying more than 200 million miles to the Red Planet, they’ll need a whole lot of it to get there and back again.
This article appears in the November 29, 2014 issue with the headline, "Extreme teams: Who has the right mental stuff for a years’ long mission to Mars?"
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