Scientists Are Devising Clever Solutions to Feed Astronauts on Mars Space Flights
Astronaut and Expedition 64 Flight Engineer Soichi Noguchi of the Japan Aerospace Exploration Agency displays Extra Dwarf Pak Choi plants growing aboard the International Space Station. The plants were grown for the Veggie study which is exploring space agriculture as a way to sustain astronauts on future missions to the Moon or Mars.
Astronauts at the International Space Station today depend on pre-packaged, freeze-dried food, plus some fresh produce thanks to regular resupply missions. This supply chain, however, will not be available on trips further out, such as the moon or Mars. So what are astronauts on long missions going to eat?
Going by the options available now, says Christel Paille, an engineer at the European Space Agency, a lunar expedition is likely to have only dehydrated foods. “So no more fresh product, and a limited amount of already hydrated product in cans.”
For the Mars mission, the situation is a bit more complex, she says. Prepackaged food could still constitute most of their food, “but combined with [on site] production of certain food products…to get them fresh.” A Mars mission isn’t right around the corner, but scientists are currently working on solutions for how to feed those astronauts. A number of boundary-pushing efforts are now underway.
The logistics of growing plants in space, of course, are very different from Earth. There is no gravity, sunlight, or atmosphere. High levels of ionizing radiation stunt plant growth. Plus, plants take up a lot of space, something that is, ironically, at a premium up there. These and special nutritional requirements of spacefarers have given scientists some specific and challenging problems.
To study fresh food production systems, NASA runs the Vegetable Production System (Veggie) on the ISS. Deployed in 2014, Veggie has been growing salad-type plants on “plant pillows” filled with growth media, including a special clay and controlled-release fertilizer, and a passive wicking watering system. They have had some success growing leafy greens and even flowers.
"Ideally, we would like a system which has zero waste and, therefore, needs zero input, zero additional resources."
A larger farming facility run by NASA on the ISS is the Advanced Plant Habitat to study how plants grow in space. This fully-automated, closed-loop system has an environmentally controlled growth chamber and is equipped with sensors that relay real-time information about temperature, oxygen content, and moisture levels back to the ground team at Kennedy Space Center in Florida. In December 2020, the ISS crew feasted on radishes grown in the APH.
“But salad doesn’t give you any calories,” says Erik Seedhouse, a researcher at the Applied Aviation Sciences Department at Embry-Riddle Aeronautical University in Florida. “It gives you some minerals, but it doesn’t give you a lot of carbohydrates.” Seedhouse also noted in his 2020 book Life Support Systems for Humans in Space: “Integrating the growing of plants into a life support system is a fiendishly difficult enterprise.” As a case point, he referred to the ESA’s Micro-Ecological Life Support System Alternative (MELiSSA) program that has been running since 1989 to integrate growing of plants in a closed life support system such as a spacecraft.
Paille, one of the scientists running MELiSSA, says that the system aims to recycle the metabolic waste produced by crew members back into the metabolic resources required by them: “The aim is…to come [up with] a closed, sustainable system which does not [need] any logistics resupply.” MELiSSA uses microorganisms to process human excretions in order to harvest carbon dioxide and nitrate to grow plants. “Ideally, we would like a system which has zero waste and, therefore, needs zero input, zero additional resources,” Paille adds.
Microorganisms play a big role as “fuel” in food production in extreme places, including in space. Last year, researchers discovered Methylobacterium strains on the ISS, including some never-seen-before species. Kasthuri Venkateswaran of NASA’s Jet Propulsion Laboratory, one of the researchers involved in the study, says, “[The] isolation of novel microbes that help to promote the plant growth under stressful conditions is very essential… Certain bacteria can decompose complex matter into a simple nutrient [that] the plants can absorb.” These microbes, which have already adapted to space conditions—such as the absence of gravity and increased radiation—boost various plant growth processes and help withstand the harsh physical environment.
MELiSSA, says Paille, has demonstrated that it is possible to grow plants in space. “This is important information because…we didn’t know whether the space environment was affecting the biological cycle of the plant…[and of] cyanobacteria.” With the scientific and engineering aspects of a closed, self-sustaining life support system becoming clearer, she says, the next stage is to find out if it works in space. They plan to run tests recycling human urine into useful components, including those that promote plant growth.
The MELiSSA pilot plant uses rats currently, and needs to be translated for human subjects for further studies. “Demonstrating the process and well-being of a rat in terms of providing water, sufficient oxygen, and recycling sufficient carbon dioxide, in a non-stressful manner, is one thing,” Paille says, “but then, having a human in the loop [means] you also need to integrate user interfaces from the operational point of view.”
Growing food in space comes with an additional caveat that underscores its high stakes. Barbara Demmig-Adams from the Department of Ecology and Evolutionary Biology at the University of Colorado Boulder explains, “There are conditions that actually will hurt your health more than just living here on earth. And so the need for nutritious food and micronutrients is even greater for an astronaut than for [you and] me.”
Demmig-Adams, who has worked on increasing the nutritional quality of plants for long-duration spaceflight missions, also adds that there is no need to reinvent the wheel. Her work has focused on duckweed, a rather unappealingly named aquatic plant. “It is 100 percent edible, grows very fast, it’s very small, and like some other floating aquatic plants, also produces a lot of protein,” she says. “And here on Earth, studies have shown that the amount of protein you get from the same area of these floating aquatic plants is 20 times higher compared to soybeans.”
Aquatic plants also tend to grow well in microgravity: “Plants that float on water, they don’t respond to gravity, they just hug the water film… They don’t need to know what’s up and what’s down.” On top of that, she adds, “They also produce higher concentrations of really important micronutrients, antioxidants that humans need, especially under space radiation.” In fact, duckweed, when subjected to high amounts of radiation, makes nutrients called carotenoids that are crucial for fighting radiation damage. “We’ve looked at dozens and dozens of plants, and the duckweed makes more of this radiation fighter…than anything I’ve seen before.”
Despite all the scientific advances and promising leads, no one really knows what the conditions so far out in space will be and what new challenges they will bring. As Paille says, “There are known unknowns and unknown unknowns.”
One definite “known” for astronauts is that growing their food is the ideal scenario for space travel in the long term since “[taking] all your food along with you, for best part of two years, that’s a lot of space and a lot of weight,” as Seedhouse says. That said, once they land on Mars, they’d have to think about what to eat all over again. “Then you probably want to start building a greenhouse and growing food there [as well],” he adds.
And that is a whole different challenge altogether.
Real-Time Monitoring of Your Health Is the Future of Medicine
Implantable sensors and other surveillance technologies offer tremendous health benefits -- and ethical challenges.
The same way that it's harder to lose 100 pounds than it is to not gain 100 pounds, it's easier to stop a disease before it happens than to treat an illness once it's developed.
In Morris' dream scenario "everyone will be implanted with a sensor" ("…the same way most people are vaccinated") and the sensor will alert people to go to the doctor if something is awry.
Bio-engineers working on the next generation of diagnostic tools say today's technology, such as colonoscopies or mammograms, are reactionary; that is, they tell a person they are sick often when it's too late to reverse course. Surveillance medicine — such as implanted sensors — will detect disease at its onset, in real time.
What Is Possible?
Ever since the Human Genome Project — which concluded in 2003 after mapping the DNA sequence of all 30,000 human genes — modern medicine has shifted to "personalized medicine." Also called, "precision health," 21st-century doctors can in some cases assess a person's risk for specific diseases from his or her DNA. The information enables women with a BRCA gene mutation, for example, to undergo more frequent screenings for breast cancer or to pro-actively choose to remove their breasts, as a "just in case" measure.
But your DNA is not always enough to determine your risk of illness. Not all genetic mutations are harmful, for example, and people can get sick without a genetic cause, such as with an infection. Hence the need for a more "real-time" way to monitor health.
Aaron Morris, a postdoctoral researcher in the Department of Biomedical Engineering at the University of Michigan, wants doctors to be able to predict illness with pinpoint accuracy well before symptoms show up. Working in the lab of Dr. Lonnie Shea, the team is building "a tiny diagnostic lab" that can live under a person's skin and monitor for illness, 24/7. Currently being tested in mice, the Michigan team's porous biodegradable implant becomes part of the body as "cells move right in," says Morris, allowing engineered tissue to be biopsied and analyzed for diseases. The information collected by the sensors will enable doctors to predict disease flareups, such as for cancer relapses, so that therapies can begin well before a person comes out of remission. The technology will also measure the effectiveness of those therapies in real time.
In Morris' dream scenario "everyone will be implanted with a sensor" ("…the same way most people are vaccinated") and the sensor will alert people to go to the doctor if something is awry.
While it may be four or five decades before Morris' sensor becomes mainstream, "the age of surveillance medicine is here," says Jamie Metzl, a technology and healthcare futurist who penned Hacking Darwin: Genetic Engineering and the Future of Humanity. "It will get more effective and sophisticated and less obtrusive over time," says Metzl.
Already, Google compiles public health data about disease hotspots by amalgamating individual searches for medical symptoms; pill technology can digitally track when and how much medication a patient takes; and, the Apple watch heart app can predict with 85-percent accuracy if an individual using the wrist device has Atrial Fibrulation (AFib) — a condition that causes stroke, blood clots and heart failure, and goes undiagnosed in 700,000 people each year in the U.S.
"We'll never be able to predict everything," says Metzl. "But we will always be able to predict and prevent more and more; that is the future of healthcare and medicine."
Morris believes that within ten years there will be surveillance tools that can predict if an individual has contracted the flu well before symptoms develop.
At City College of New York, Ryan Williams, assistant professor of biomedical engineering, has built an implantable nano-sensor that works with a florescent wand to scope out if cancer cells are growing at the implant site. "Instead of having the ovary or breast removed, the patient could just have this [surveillance] device that can say 'hey we're monitoring for this' in real-time… [to] measure whether the cancer is maybe coming back,' as opposed to having biopsy tests or undergoing treatments or invasive procedures."
Not all surveillance technologies that are being developed need to be implanted. At Case Western, Colin Drummond, PhD, MBA, a data scientist and assistant department chair of the Department of Biomedical Engineering, is building a "surroundable." He describes it as an Alexa-style surveillance system (he's named her Regina) that will "tell" the user, if a need arises for medication, how much to take and when.
Bioethical Red Flags
"Everyone should be extremely excited about our move toward what I call predictive and preventive health care and health," says Metzl. "We should also be worried about it. Because all of these technologies can be used well and they can [also] be abused." The concerns are many layered:
Discriminatory practices
For years now, bioethicists have expressed concerns about employee-sponsored wellness programs that encourage fitness while also tracking employee health data."Getting access to your health data can change the way your employer thinks about your employability," says Keisha Ray, assistant professor at the University of Texas Health Science Center at Houston (UTHealth). Such access can lead to discriminatory practices against employees that are less fit. "Surveillance medicine only heightens those risks," says Ray.
Who owns the data?
Surveillance medicine may help "democratize healthcare" which could be a good thing, says Anita Ho, an associate professor in bioethics at both the University of California, San Francisco and at the University of British Columbia. It would enable easier access by patients to their health data, delivered to smart phones, for example, rather than waiting for a call from the doctor. But, she also wonders who will own the data collected and if that owner has the right to share it or sell it. "A direct-to-consumer device is where the lines get a little blurry," says Ho. Currently, health data collected by Apple Watch is owned by Apple. "So we have to ask bigger ethical questions in terms of what consent should be required" by users.
Insurance coverage
"Consumers of these products deserve some sort of assurance that using a product that will predict future needs won't in any way jeopardize their ability to access care for those needs," says Hastings Center bioethicist Carolyn Neuhaus. She is urging lawmakers to begin tackling policy issues created by surveillance medicine, now, well ahead of the technology becoming mainstream, not unlike GINA, the Genetic Information Nondiscrimination Act of 2008 -- a federal law designed to prevent discrimination in health insurance on the basis of genetic information.
And, because not all Americans have insurance, Ho wants to know, who's going to pay for this technology and how much will it cost?
Trusting our guts
Some bioethicists are concerned that surveillance technology will reduce individuals to their "risk profiles," leaving health care systems to perceive them as nothing more than a "bundle of health and security risks." And further, in our quest to predict and prevent ailments, Neuhaus wonders if an over-reliance on data could damage the ability of future generations to trust their gut and tune into their own bodies?
It "sounds kind of hippy-dippy and feel-goodie," she admits. But in our culture of medicine where efficiency is highly valued, there's "a tendency to not value and appreciate what one feels inside of their own body … [because] it's easier to look at data than to listen to people's really messy stories of how they 'felt weird' the other day. It takes a lot less time to look at a sheet, to read out what the sensor implanted inside your body or planted around your house says."
Ho, too, worries about lost narratives. "For surveillance medicine to actually work we have to think about how we educate clinicians about the utility of these devices and how to how to interpret the data in the broader context of patients' lives."
Over-diagnosing
While one of the goals of surveillance medicine is to cut down on doctor visits, Ho wonders if the technology will have the opposite effect. "People may be going to the doctor more for things that actually are benign and are really not of concern yet," says Ho. She is also concerned that surveillance tools could make healthcare almost "recreational" and underscores the importance of making sure that the goals of surveillance medicine are met before the technology is unleashed.
"We can't just assume that any of these technologies are inherently technologies of liberation."
AI doesn't fix existing healthcare problems
"Knowing that you're going to have a fall or going to relapse or have a disease isn't all that helpful if you have no access to the follow-up care and you can't afford it and you can't afford the prescription medication that's going to ward off the onset," says Neuhaus. "It may still be worth knowing … but we can't fool ourselves into thinking that this technology is going to reshape medicine in America if we don't pay attention to … the infrastructure that we don't currently have."
Race-based medicine
How surveillances devices are tested before being approved for human use is a major concern for Ho. In recent years, alerts have been raised about the homogeneity of study group participants — too white and too male. Ho wonders if the devices will be able to "accurately predict the disease progression for people whose data has not been used in developing the technology?" COVID-19 has killed Black people at a rate 2.5 time greater than white people, for example, and new, virtual clinical research is focused on recruiting more people of color.
The Biggest Question
"We can't just assume that any of these technologies are inherently technologies of liberation," says Metzl.
Especially because we haven't yet asked the 64-thousand dollar question: Would patients even want to know?
Jenny Ahlstrom is an IT professional who was diagnosed at 43 with multiple myeloma, a blood cancer that typically attacks people in their late 60s and 70s and for which there is no cure. She believes that most people won't want to know about their declining health in real time. People like to live "optimistically in denial most of the time. If they don't have a problem, they don't want to really think they have a problem until they have [it]," especially when there is no cure. "Psychologically? That would be hard to know."
Ahlstrom says there's also the issue of trust, something she experienced first-hand when she launched her non-profit, HealthTree, a crowdsourcing tool to help myeloma patients "find their genetic twin" and learn what therapies may or may not work. "People want to share their story, not their data," says Ahlstrom. "We have been so conditioned as a nation to believe that our medical data is so valuable."
Metzl acknowledges that adoption of new technologies will be uneven. But he also believes that "over time, it will be abundantly clear that it's much, much cheaper to predict and prevent disease than it is to treat disease once it's already emerged."
Beyond cost, the tremendous potential of these technologies to help us live healthier and longer lives is a game-changer, he says, as long as we find ways "to ultimately navigate this terrain and put systems in place ... to minimize any potential harms."
How Smallpox Was Wiped Off the Planet By a Vaccine and Global Cooperation
The world's last recorded case of endemic smallpox was in Ali Maow Maalin, of Merka, Somalia, in October 1977. He made a full recovery.
For 3000 years, civilizations all over the world were brutalized by smallpox, an infectious and deadly virus characterized by fever and a rash of painful, oozing sores.
Doctors had to contend with wars, floods, and language barriers to make their campaign a success.
Smallpox was merciless, killing one third of people it infected and leaving many survivors permanently pockmarked and blind. Although smallpox was more common during the 18th and 19th centuries, it was still a leading cause of death even up until the early 1950s, killing an estimated 50 million people annually.
A Primitive Cure
Sometime during the 10th century, Chinese physicians figured out that exposing people to a tiny bit of smallpox would sometimes result in a milder infection and immunity to the disease afterward (if the person survived). Desperate for a cure, people would huff powders made of smallpox scabs or insert smallpox pus into their skin, all in the hopes of getting immunity without having to get too sick. However, this method – called inoculation – didn't always work. People could still catch the full-blown disease, spread it to others, or even catch another infectious disease like syphilis in the process.
A Breakthrough Treatment
For centuries, inoculation – however imperfect – was the only protection the world had against smallpox. But in the late 18th century, an English physician named Edward Jenner created a more effective method. Jenner discovered that inoculating a person with cowpox – a much milder relative of the smallpox virus – would make that person immune to smallpox as well, but this time without the possibility of actually catching or transmitting smallpox. His breakthrough became the world's first vaccine against a contagious disease. Other researchers, like Louis Pasteur, would use these same principles to make vaccines for global killers like anthrax and rabies. Vaccination was considered a miracle, conferring all of the rewards of having gotten sick (immunity) without the risk of death or blindness.
Scaling the Cure
As vaccination became more widespread, the number of global smallpox deaths began to drop, particularly in Europe and the United States. But even as late as 1967, smallpox was still killing anywhere from 10 to 15 million people in poorer parts of the globe. The World Health Assembly (a decision-making body of the World Health Organization) decided that year to launch the first coordinated effort to eradicate smallpox from the planet completely, aiming for 80 percent vaccine coverage in every country in which the disease was endemic – a total of 33 countries.
But officials knew that eradicating smallpox would be easier said than done. Doctors had to contend with wars, floods, and language barriers to make their campaign a success. The vaccination initiative in Bangladesh proved the most challenging, due to its population density and the prevalence of the disease, writes journalist Laurie Garrett in her book, The Coming Plague.
In one instance, French physician Daniel Tarantola on assignment in Bangladesh confronted a murderous gang that was thought to be spreading smallpox throughout the countryside during their crime sprees. Without police protection, Tarantola confronted the gang and "faced down guns" in order to immunize them, protecting the villagers from repeated outbreaks.
Because not enough vaccines existed to vaccinate everyone in a given country, doctors utilized a strategy called "ring vaccination," which meant locating individual outbreaks and vaccinating all known and possible contacts to stop an outbreak at its source. Fewer than 50 percent of the population in Nigeria received a vaccine, for example, but thanks to ring vaccination, it was eradicated in that country nonetheless. Doctors worked tirelessly for the next eleven years to immunize as many people as possible.
The World Health Organization declared smallpox officially eradicated on May 8, 1980.
A Resounding Success
In November 1975, officials discovered a case of variola major — the more virulent strain of the smallpox virus — in a three-year-old Bangladeshi girl named Rahima Banu. Banu was forcibly quarantined in her family's home with armed guards until the risk of transmission had passed, while officials went door-to-door vaccinating everyone within a five-mile radius. Two years later, the last case of variola major in human history was reported in Somalia. When no new community-acquired cases appeared after that, the World Health Organization declared smallpox officially eradicated on May 8, 1980.
Because of smallpox, we now know it's possible to completely eliminate a disease. But is it likely to happen again with other diseases, like COVID-19? Some scientists aren't so sure. As dangerous as smallpox was, it had a few characteristics that made eradication possibly easier than for other diseases. Smallpox, for instance, has no animal reservoir, meaning that it could not circulate in animals and resurge in a human population at a later date. Additionally, a person who had smallpox once was guaranteed immunity from the disease thereafter — which is not the case for COVID-19.
In The Coming Plague, Japanese physician Isao Arita, who led the WHO's Smallpox Eradication Unit, admitted to routinely defying orders from the WHO, mobilizing to parts of the world without official approval and sometimes even vaccinating people against their will. "If we hadn't broken every single WHO rule many times over, we would have never defeated smallpox," Arita said. "Never."
Still, thanks to the life-saving technology of vaccines – and the tireless efforts of doctors and scientists across the globe – a once-lethal disease is now a thing of the past.