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.
Dana Lewis, pictured in Mount Vernon in 2017, worked with her engineer husband to design an artificial pancreas system to manage her type 1 diabetes.
For years, a continuous glucose monitor would beep at night if Dana Lewis' blood sugar measured too high or too low. At age 14, she was diagnosed with type 1 diabetes, an autoimmune disease that destroys insulin-producing cells in the pancreas.
The FDA just issued its first warning to the DIY diabetic community, after one patient suffered an accidental insulin overdose.
But being a sound sleeper, the Seattle-based independent researcher, now 30, feared not waking up. That concerned her most when she would run, after which her glucose dropped overnight. Now, she rarely needs a rousing reminder to alert her to out-of-range blood glucose levels.
That's because Lewis and her husband, Scott Leibrand, a network engineer, developed an artificial pancreas system—an algorithm that calculates adjustments to insulin delivery based on data from the continuous glucose monitor and her insulin pump. When the monitor gives a reading, she no longer needs to press a button. The algorithm tells the pump how much insulin to release while she's sleeping.
"Most of the time, it's preventing the frequent occurrences of high or low blood sugars automatically," Lewis explains.
Like other do-it-yourself device innovations, home-designed artificial pancreas systems are not approved by the Food and Drug Administration, so individual users assume any associated risks. Experts recommend that patients consult their doctor before adopting a new self-monitoring approach and to keep the clinician apprised of their progress.
DIY closed-loop systems can be uniquely challenging, according to the FDA. Patients may not fully comprehend how the devices are intended to work or they may fail to recognize the limitations. The systems have not been evaluated under quality control measures and pose risks of inappropriate dosing from the automated algorithm or potential incompatibility with a patient's other medications, says Stephanie Caccomo, an FDA spokeswoman.
Earlier this month, in fact, the FDA issued its first warning to the DIY diabetic community, which includes thousands of users, after one patient suffered an accidental insulin overdose.
Patients who built their own systems from scratch may be more well-versed in the operations, while those who are implementing unapproved designs created by others are less likely to be familiar with their intricacies, she says.
"Malfunctions or misuse of automated-insulin delivery systems can lead to acute complications of hypo- and hyperglycemia that may result in serious injury or death," Caccomo cautions. "FDA provides independent review of complex systems to assess the safety of these nontransparent devices, so that users do not have to be software/hardware designers to get the medical devices they need."
Only one hybrid closed-loop technology—the MiniMed 670G System from Minneapolis-based Medtronic—has been FDA-approved for type 1 use since September 2016. The term "hybrid" indicates that the system is not a fully automatic closed loop; it still requires minimal input from patients, including the need to enter mealtime carbohydrates, manage insulin dosage recommendations, and periodically calibrate the sensor.
Meanwhile, some tech-savvy people with type 1 diabetes have opted to design their own systems. About one-third of the DIY diabetes loopers are children whose parents have built them a closed system, according to Lewis' website.
Lewis began developing her system in 2014, well before Medtronic's device hit the market. "The choice to wait is not a luxury," she says, noting that "diabetes is inherently dangerous," whether an individual relies on a device to inject insulin or administers it with a syringe.
Hybrid closed-loop insulin delivery improves glucose control while decreasing the risk of low blood sugar in patients of various ages with less than optimally controlled type 1 diabetes, according to a study published in The Lancet last October. The multi-center randomized trial, conducted in the United Kingdom and the United States, spanned 12 weeks and included adults, adolescents, and children aged 6 years and older.
"We have compelling data attesting to the benefits of closed-loop systems," says Daniel Finan, research director at JDRF (formerly the Juvenile Diabetes Research Foundation) in New York, a global organization funding the study.
Medtronic's system costs between $6,000 and $9,000. However, end-user pricing varies based on an individual's health plan. It is covered by most insurers, according to the device manufacturer.
To give users more choice, in 2017 JDRF launched the Open Protocol Automated Insulin Delivery Systems initiative to collaborate with the FDA and experts in the do-it-yourself arena. The organization hopes to "forge a new regulatory paradigm," Finan says.
As diabetes management becomes more user-controlled, there is a need for better coordination. "We've had insulin pumps for a very long time, but having sensors that can detect blood sugars in real time is still a very new phenomenon," says Leslie Lam, interim chief in the division of pediatric endocrinology and diabetes at The Children's Hospital at Montefiore in the Bronx, N.Y.
"There's a lag in the integration of this technology," he adds. Innovators are indeed working to bring new products to market, "but on the consumer side, people want that to be here now instead of a year or two later."
The devices aren't foolproof, and mishaps can occur even with very accurate systems. For this reason, there is some reluctance to advocate for universal use in children with type 1 diabetes. Supervision by a parent, school nurse, and sometimes a coach would be a prudent precaution, Lam says.
People engage in "this work because they are either curious about it themselves or not getting the care they need from the health care system, or both."
Remaining aware of blood sugar levels and having a backup plan are essential. "People still need to know how to give injections the old-school way," he says.
To ensure readings are correct on Medtronic's device, users should check their blood sugar with traditional finger pricking at least five or six times per day—before every meal and whenever directed by the system, notes Elena Toschi, an endocrinologist and director of the Young Adult Clinic at Joslin Diabetes Center, an affiliate of Harvard Medical School.
"There can be pump failure and cross-talking failure," she cautions, urging patients not to stop being vigilant because they are using an automated device. "This is still something that can happen; it doesn't eliminate that."
While do-it-yourself devices help promote autonomy and offer convenience, the lack of clinical trial data makes it difficult for clinicians and patients to assess risks versus benefits, says Lisa Eckenwiler, an associate professor in the departments of philosophy and health administration and policy at George Mason University in Fairfax, Va.
"What are the responsibilities of physicians in that context to advise patients?" she questions. Some clinicians foresee the possibility that "down the road, if things go awry" with disease management, that could place them "in a moral quandary."
Whether it's controlling diabetes, obesity, heart disease or asthma, emerging technologies are having a major influence on individuals' abilities to stay on top of their health, says Camille Nebeker, an assistant professor in the School of Medicine at the University of California, San Diego, and founder and director of its Research Center for Optimal Data Ethics.
People engage in "this work because they are either curious about it themselves or not getting the care they need from the health care system, or both," she says. In "citizen science communities," they may partner in participant-led research while gaining access to scientific and technical expertise. Others "may go it alone in solo self-tracking studies or developing do-it-yourself technologies," which raises concerns about whether they are carefully considering potential risks and weighing them against possible benefits.
Dana Lewis admits that "using do-it-yourself systems might not be for everyone. But the advances made in the do-it-yourself community show what's possible for future commercial developments, and give a lot of hope for improved quality of life for those of us living with type 1 diabetes."
The Grim Reaper Can Now Compost Your Body
An artist's rendering of a future Recompose facility in Washington state, with reusable modular vessels that convert human remains to soil.
Ultra-green Seattle isn't just getting serious about living eco-friendly, but dying that way, too. As of this week, Washington is officially the first state to allow citizens to compost their own dead bodies.
Their bodies, including bones, were converted into clean, odorless soil free of harmful pathogens.
The Lowdown
Keep in mind this doesn't mean dumping your relative in a nearby river. Scientists and organizations have ways to help Mother Nature process the remains. For instance, the late actor Luke Perry reportedly was buried in a mushroom suit. Perry's garment is completely biodegradable and the attached microorganisms help the decomposition process cleanly and efficiently.
A biodegradable burial requires only a fraction of the energy used for cremation and can save a metric ton of CO2. The body decomposes in about a month. Besides a mushroom suit, another option coming down the pike in Washington state is to have your body converted directly into soil in a special facility.
A pilot study last summer by a public benefit corporation called Recompose signed up six terminally ill people who donated their remains for such research. Their bodies, including bones, were converted into clean, odorless soil free of harmful pathogens. That soil—about a cubic yard per person--could then be returned after 30 days to the subjects' families.
Green burials open the door to creative memorials. A tree or garden could be planted with your soil. This method provides a climate-friendly alternative to traditional funerals, circumventing toxic embalming fluid, expensive casket materials and other ecological overhead. The fertile soil could also be given to conservationist organizations.
Next Up
The new legislation in Washington will take effect May 1, 2020. The Pacific Northwest state has one of the highest cremation rates in the nation at 78 percent, only second to Nevada. Rising climate change and increased interest in death management will only speed this discussion to the forefront in other states.
A biodegradable burial requires only a fraction of the energy used for cremation and can save a metric ton of CO2.
It's also worth noting Perry wasn't buried in Washington State, but in Tennessee. It is unknown where exactly he was laid to rest, nor if it was done under a legal precedent or special exception.
According to the Green Burial Council, each state varies on how and where you can bury someone. Home burials are usually legal, but to do so requires establishing an official cemetery area on the property. How someone is buried has even more dynamic legislation. There will be new discussions about how neighbors contend with nearby decomposing bodies, legal limitations to private burial techniques, and other issues never addressed before in modern mainstream America.
Open Questions
It's unclear if green burials will be commonplace for those with less financial means or access. Mushroom suits average a couple thousand dollars, making them more expensive than a low-end casket. There are also the less obvious expenses, including designating the place of burial, and getting proper burial support and guidance. In short, you likely won't go to the local funeral home and be taken care of properly. It is still experimental.
As for "natural organic reduction" (converting human remains to soil in reusable modular vessels), Recompose is still figuring out its pricing for Washington residents, but expects the service to cost more than cremation and less than a conventional burial.
For now, environmentally sustainable death care may be comparable to vegetarianism in the 1970s or solar paneling in the 1980s: A discussion among urbanites and upwardly-mobile financial classes, but not yet an accessible option for the average American. It's not a coincidence that the new Washington law received support in Seattle, one of the top 10 wealthiest cities in America. A similar push may take off in less affluent areas if ecological concerns drive a demand for affordable green burial options.
Until then, your neighborhood mortician still has the death business on lock.