Interview Kate Greene

‘In space, you know the physics of how you’re going to die’: Kate Greene

Image credit: Nick Smith

Second-in-command on Nasa’s first simulated Mars mission, 'HI-SEAS', Kate Greene discusses what it takes to be a modern astronaut and why today’s ‘right stuff’ is different from what was required on the Apollo missions of the 20th century.

“There’s really nothing normal about six adults making believe they live on another planet,” says Kate Greene. She’s reflecting on an experience in which she lived in a geodesic dome, only ventured outside in a fake space suit, bathed with wet wipes, breathed recycled air and never felt real sunlight on her skin for four months.

Green, who is by academic training a laser physicist, is also what she calls an ‘almost-astronaut’. The term is self-effacing, used deliberately to maintain a respectful distance between her and ‘real’ space travellers who have buckled up in the command module on the launch pad. Yet Greene has played a vital role in our understanding of how human spaceflight to Mars might look one day. As an ‘analogue’ crew member, she lived and worked as a scientist under simulated Martian conditions as part of a Nasa human research programme.

The Hawaii Space Exploration Analog and Simulation (HI-SEAS) was a Nasa-funded project that ran for five years from 2013, in six missions to provide scientific insight into astronaut response and adaptation to living on Mars, should we ever get there. Greene was second-in-command of a six-member team in the project’s first instalment. “Its purpose was to collect physiological data on crews during long-duration simulated Mars missions,” with a focus on diet and nutrition, she explains, (although there were “countless” other scientific observations and experiments). Her experiences are recorded in her new book ‘Once Upon a Time I Lived on Mars’.

Greene, who as well as being a laser physicist is a published poet, became involved in HI-SEAS by answering an ‘open-call’ advertisement on a whim. Although the project required applicants to have baseline qualifications for astronaut training (which she had), she had no relevant experience, having spent most of her post-academia career as a science journalist. “But it turned out the people selecting candidates to be an ‘almost-astronaut’ found that to be an acceptable characteristic.” Looking back on the mission, Greene feels Nasa was “looking for a broader spectrum of life experiences. Possibly the reason for that,” she ventures, “is that while we were going to be under the microscope to a certain extent, we weren’t going to undergo the relentless scrutiny that most Nasa astronauts are required to go through in justifying who’s the best of the best. I think what they were looking for was a diverse crew coming from a variety of backgrounds.”

The backgrounds of Greene’s five crewmates were in space systems research, engineering, materials science, geology and education outreach. I put it to Greene that this is significantly different from the traditional hero image of space explorers of the 1960s, when astronauts on the Apollo, Gemini and Mercury programmes tended to be all-American, 30-something white men with engineering or military test pilot backgrounds. “You can see why,” says Greene. “Back then, Apollo’s mission was to get to the Moon, so astronauts were part of the process, part of the engineering. You only had to survive for a few days, so it was all about efficiency.” But going to Mars is different. With the round trips potentially taking years, simply tolerating conditions while getting the job done needs to make way for quality of life for the astronauts. “You’re going to be away from home for a long time and so you’ve got to think about things like your mental wellbeing and what you’re going to eat.”

Four months isolated in a geodesic dome high on the slopes of Hawaii’s Mauna Loa volcano in the middle of the Pacific Ocean might sound (to some at least) like a holiday in paradise. Yet for Greene, this was a far cry from “a regular vacation”. She recalls arriving a week in advance of the start of the project, following a short practice run at a desert research station in Utah, “where we got to know each other a little better as a crew and to figure out what our experiments might be”.

During that first week, the crew had team-building conversations about what psychological pressure points were on them in the simulation, or ‘analogue’ (the preferred astronaut term). They discussed under what sort of circumstances individuals might leave the simulation, clearly one of the major differences between living in the analogue and the real thing. “In space, you know the physics of how you’re going to die,” says Greene, referring to the strict protocols for throwing a fellow astronaut ‘overboard’ in mission-critical scenarios, with its inevitable fatal outcome.

At this point she reminds me of the second-ever American spacewalk that nearly ended in disaster when in 1965 on the Gemini IV mission Nasa astronaut Gene Cernan experienced difficulties returning to the craft, opening up the possibility of his crewmate Tom Stafford having to close the hatch and return to Earth without him. This episode was to lead to immediate adoption of underwater astronaut training back on Earth, with Cernan being somewhat understandably one of the first to sign up after his botched EVA (extra-vehicular activity).

These first rudimentary pre-mission simulations were to evolve into analogues that would “let engineers test equipment and play out scenarios that might arise on expeditions in deep space. But increasingly, these faux space missions are used to probe astronaut psychology and sociology – the most unpredictable element in any human expedition – to study coping strategies potentially useful on a long journey far away from Earth.”

‘I at no point embraced the fantasy fully. I embraced the restrictions’.

Kate Greene

Back on Hawaii, the pre-mission fortnight was also spent “fiddling with our space suits and getting last minute supplies”. Also, since this was the first HI-SEAS mission, there were technical teething problems to overcome, such as finalising electrical systems in the astronaut habitat dome, creating a one-day delay. But once everything was in place, “we arrived at night, just as you would on Mars, the idea being that we would go to sleep and when we woke up, we’d be on another planet. We arrived by van and entered the dome that smelled a bit like a new car, or maybe a new spaceship smell is more accurate (it’s the off-gassing of the vinyl technically).” A brief discussion with architects and the crew were left to their own devices: “We explored our own rooms that we were very excited about, and then went to bed. When we woke up, we spent the first few days organising our food supplies.”

When you look at four months’ food supplies for six people, says Greene, you are confronted with a sight “that looks like something you’ve never seen before. There was just so much of it.” After the food was organised, it was simply a question of “setting up the mission experiments and running them.

“It quickly became a very domestic experience, living communally, eating, cleaning up after yourself and doing your work. The work itself included a lot of food experiments, monitoring how your sense of smell changes with time, or your nasal patency (how much oxygen you’re taking in through your nose).” Such was the intensity and volume of scientific work during the analogue that at any given point Greene was behind in filling out survey documentation put in place to monitor anything and everything from her reaction to having foot swabs as part of a microbial sample test, to her inner thoughts on what deep space travel meant to her personally. “There were so many little tasks to do all the time to keep those science projects running. If you talk to any of the guys on the Space Station, they’ll tell you that they’re busy all the time.” Everything was about data, says Greene.

However, for all the surface resemblance to a space mission, the HI-SEAS analogue was just that, says Greene – a simulation in which she always knew there were never going to be the sort of life-or-death scenarios that could face astronauts at least 30 million miles from home (the exact distance between Earth and Mars varies wildly with time, as they are on different orbits around the Sun). She never found it particularly difficult to accept the idea that she was an ‘almost-astronaut’ on Mars, where “things got pretty normal quite fast”, while on the other hand, she admits she never completely bought into the illusion. “I always knew I was going back to Earth,” she says, a Freudian slip perhaps betraying that the illusion had become more established in her mind than she might initially admit.

When pushed on the issue of whether she actually believed she was no longer on Earth, she says: “Controversially, no. I at no point embraced the fantasy fully. I embraced the restrictions. And I felt them. I felt the frustrations of the communication delay and the inability to have a real-time conversation with anyone outside of the simulation.” Stripped of electronic devices and social media, “our sole regular contact with Earth was through email. Since Mars is extremely far away, and photons can only fly so fast, our email transmissions were delayed by 20 minutes each way to mimic the actual communication lag to be experienced by Martian explorers.”

The closest she got to an off-world experience was in the preparatory mission in Utah, “where I let myself relax. I was outside at the time looking at the rocky horizon and I tried to let myself imagine what it must be like to be an astronaut on Mars. The moment I felt most on Mars I was in Utah. But in the same moment, I was right back on Earth. It’s a common experience for astronauts to dream of home.”

Meanwhile, the repetitive nature of the Martian simulation created the effect of time becoming meaningless: “You’d ask yourself if it’s Wednesday or October. There seemed to be no difference between a day and a month, and I experienced a lot of elasticity of time.” I suggest to her that this would have been good mental preparation for the series of Covid-related lockdowns she’s experienced in her small apartment in New York. You would think so, she says, but it’s not the case. “Although it might seem oddly prescient to have written a book about the experience of living on Mars that it so outwardly similar to life during the pandemic, it is different.” Life in the dome on Hawaii was easier, she says, not least because there was always a detailed action plan. “All this,” she says waving her hand vaguely at the Big Apple, “is kind of mushy. It doesn’t make any sense.”

Although Greene was occupied in conducting reams of endless scientific data-​gathering experiments, the inescapable conclusion is that it was the crew that was the experiment. She is happy to accept that “you could see it as being” a case that she and her five crewmates were the lab rats under the microscope, with data analysts back on Earth working out what the 21st-

century version of the ‘right stuff’ would be in terms of long-duration excursions into deep space rather than flag-planting weekend trips to the Moon. “I think it’s important to state that I really did think that I was contributing something to the future of space flight, and potentially this data can be a part of human space exploration history.”

Greene says that because of analogues such as the HI-SEAS programme, the science and engineering community is able to amass “plenty of data to design a safer, better mission beyond low-Earth orbit”. While she is happy to have played her part in that process, she admits the “push to go further into space has left me wondering what assumptions get built into space systems and mission designs”, leading her to wonder further what it is that makes us “want to go in the first place. What is it exactly that propels us up and out?”

She takes a few moments to make the point that much early exploration of our home planet, though often dressed up in the guise of the pursuit of knowledge or scientific discovery, was, as we are now becoming increasingly more aware, “rooted in colonialism and subjugation. What kind of remnant legacies and unexamined assumptions thread through today’s discussions to colonise Mars? And if there ever is a human mission to Mars, who gets to go? Who decides?” Yet she also sees deep space exploration as bringing with it the opportunity to inspire new ways of sustainability for both our lives and our ecosystems back on Earth. “What kind of wisdom might launch inside those spaceships? What kind of wisdom might we grow here at home?”

‘One Upon a Time I Lived on Mars’ is published by Icon Books, £14.99

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