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.
Scientists: Don’t Leave Religious Communities Out in the Cold
A star of David reflects the perspective of a Rabbi/M.D. on an important question about the future of society.
[Editor's Note: This essay is in response to our current Big Question series: "How can the religious and scientific communities work together to foster a culture that is equipped to face humanity's biggest challenges?"]
I humbly submit that the question should be rephrased: How can the religious and scientific communities NOT work together to face humanity's biggest challenges? The stakes are higher than ever before, and we simply cannot afford to go it alone.
I believe in evolution -- the evolution of the relationship of science and religion.
The future of the world depends on our collaboration. I believe in evolution -- the evolution of the relationship of science and religion. Science and religion have lived in alternately varying relationships ranging from peaceful coexistence to outright warfare. Today we have evolved and have begun to embrace the biological relationship of mutualism. This is in part due to the advances in medicine and science.
Previous scientific discoveries and paradigm shifts precipitated varying theological responses. With Copernicus, we grappled with the relationship of the earth to the universe. With Darwin, we re-evaluated the relationship of man to the other creatures on earth. However, as theologically complex as these debates were, they had no practical relevance to the common man. Indeed, it was possible for people to live their entire lives happily without pondering these issues.
In the 21st century, the microscope is honing in further, with discoveries relating to the understanding of the very nature and composition of the human being, both body and mind/soul. Thus, as opposed to the past, the implications of the latest scientific advances directly affect the common man. The religious implications are not left to the ivory tower theologians. Regular people are now confronted with practical religious questions previously unimagined.
For example, in the field of infertility, if a married woman undergoes donor insemination, is she considered an adulteress? If a woman of one faith gestates the child of another faith, to whose faith does the child belong? If your heart is failing, can you avail yourself of stem cells derived from human embryos, or would you be considered an accomplice to murder? Would it be preferable to use artificially derived stem cells if they are available?
The implications of our current debates are profound, and profoundly personal. Science is the great equalizer. Every living being can potentially benefit from medical advances. We are all consumers of the scientific advances, irrespective of race or religion. As such, we all deserve a say in their development.
If the development of the science is collaborative, surely the contemplation of its ethical/religious applications should likewise be.
With gene editing, uterus transplants, head transplants, artificial reproductive seed, and animal-human genetic combinations as daily headlines, we have myriad ethical dilemmas to ponder. What limits should we set for the uses of different technologies? How should they be financed? We must even confront the very definition of what it means to be human. A human could receive multiple artificial transplants, 3D printed organs, genetic derivatives, or organs grown in animals. When does a person become another person or lose his identity? Will a being produced entirely from synthetic DNA be human?
In the Middle Ages, it was possible for one person to master all of the known science, and even sometimes religion as well, such as the great Maimonides. In the pre-modern era, discoveries were almost always attributed to one individual: Jenner, Lister, Koch, Pasteur, and so on. Today, it is impossible for any one human being to master medicine, let alone ethics, religion, etc. Advances are made not usually by one person but by collaboration, often involving hundreds, if not thousands of people across the globe. We cite journal articles, not individuals. Furthermore, the magnitude and speed of development is staggering. Add artificial intelligence and it will continue to expand exponentially.
If the development of the science is collaborative, surely the contemplation of its ethical/religious applications should likewise be. The issues are so profound that we need all genes on deck. The religious community should have a prominent seat at the table. There is great wisdom in the religious traditions that can inform contemporary discussions. In addition, the religious communities are significant consumers of, not to mention contributors to, the medical technology.
An ongoing dialogue between the scientific and religious communities should be an institutionalized endeavor, not a sporadic event, reactive to a particular discovery. The National Institutes of Health or other national organizations could provide an online newsletter designed for the clergy with a summary of the latest developments and their potential applications. An annual meeting of scientists and religious leaders could provide a forum for the scientists to appreciate the religious ramifications of their research (which may be none as well) and for the clergy to appreciate the rapidly developing fields of science and the implications for their congregants. Theological seminaries must include basic scientific literacy as part of their curricula.
We need the proper medium of mutual respect and admiration, despite healthy disagreement.
How do we create a "culture"? Microbiological cultures take time and require the proper medium for maximal growth. If one of the variables is altered, the culture can be affected. To foster a culture of continued successful collaboration between scientists and religious communities, we likewise need the proper medium of mutual respect and admiration, despite healthy disagreement.
The only way we can navigate these unchartered waters is through constant, deep and meaningful collaboration every single step of the way. By cultivating a mutualistic relationship we can inform, caution and safeguard each other to maximize the benefits of emerging technologies.
[Ed. Note: Don't miss the other perspectives in this Big Question series, from a science scholar and a Reverend/molecular geneticist.]
Why the Pope Should Officially Embrace Biotechnology
Pope Francis processing into Mass at St. Peter's Square.
[Editor's Note: This essay is in response to our current Big Question series: "How can the religious and scientific communities work together to foster a culture that is equipped to face humanity's biggest challenges?"]
In May 2015, Pope Francis issued an encyclical with the subtitle "On Care for Our Common Home." The letter addressed various environmental issues, such as pollution and climate change, and it reminded all of us that we are to steward the Earth, not plunder it.
Without question, biotechnology has saved the lives of millions – perhaps billions – of people.
The Pope's missive demonstrates that he is both theologically sound and scientifically literate, a very rare combination. That is why he should now author an encyclical urging the world to embrace the life-giving promise of biotechnology.
Without question, biotechnology has saved the lives of millions – perhaps billions – of people. Arguably, vaccines were the most important invention in the history of mankind. It is thought that, in the 20th century alone, at least 300 million people were killed by smallpox. Today, the number is zero, thanks to vaccination. Other killers, such as measles, diphtheria, meningitis, and diarrhea, are kept at bay because of vaccines.
Biotechnology has also saved the lives of diabetics. At one time, insulin was extracted from pig pancreases, and there were fears that we would run out of it. Then, in the 1970s, crucial advances in biotechnology allowed for the gene that encodes human insulin to be expressed in bacteria. Today, diabetics can get extremely pure insulin thanks to this feat of genetic modification.
Likewise, genetic modification has improved the environment and the lives of farmers all over the world, none more so than those living in developing countries. According to a meta-analysis published in PLoS ONE, GMOs have "reduced chemical pesticide use by 37%, increased crop yields by 22%, and increased farmer profits by 68%."
Even better, GMOs also could help improve the lives of non-farmers. In poor parts of the world, malnutrition is still extremely common. People whose diets consist mostly of rice, for example, often suffer from vitamin A deficiency, which can lead to blindness. Golden Rice, which was genetically modified to contain a vitamin A precursor, was created and given away for free in an act of humanitarianism. Other researchers have created a genetically modified cassava to help combat iron and zinc deficiencies among children in Africa.
Despite these groundbreaking advances, the public is turning against biotechnology.
Biotechnology has also helped women with mitochondrial disease bear healthy children. Children inherit their mitochondria, the powerhouses of our cells, solely from their mothers. Mitochondrial defects can have devastating health consequences. Using what is colloquially called the "three-parent embryo technique," a healthy woman donates an egg. The nucleus of that egg is removed, and that of the mother-to-be is put in its place. Then, the egg is fertilized using conventional in vitro fertilization. In April 2016, the world's first baby was born using this technique.
Yet, despite these groundbreaking advances, the public is turning against biotechnology. Across America and Europe, anti-vaccine activists have helped usher in a resurgence of entirely preventable diseases, such as measles. Anti-GMO activists have blocked the implementation of Golden Rice. And other activists decry reproductive technology as "playing God."
Nonsense. These technologies improve overall welfare and save lives. Those laudable goals are shared by all the world's major religions as part of their efforts to improve the human condition. That is why it is vitally important, if science is to succeed in eradicating illness, that it gets a full-throated endorsement from powerful religious leaders.
In his 2015 encyclical, Pope Francis wrote:
Any technical solution which science claims to offer will be powerless to solve the serious problems of our world if humanity loses its compass, if we lose sight of the great motivations which make it possible for us to live in harmony, to make sacrifices and to treat others well.
He is correct. Indeed, when people are protesting life-saving vaccines, we have lost not only our moral compass but our intellect, too.
Imagine the impact he could have if Pope Francis issued an encyclical titled "On Protecting Our Most Vulnerable." He could explain that some children, stricken with cancer or suffering from an immunological disease, are unable to receive vaccines. Therefore, we all have a moral duty to be vaccinated in order to protect them through herd immunity.
Or imagine the potential impact of an encyclical titled "On Feeding the World," in which the Pope explained that rich countries have an obligation to poorer ones to feed them by all means necessary, including the use of biotechnology. If Muslim, Buddhist, and Hindu scholars throughout Asia and Africa also embraced the message, its impact could be multiplied.
In order to be successful, science needs religion; in order to be practical, religion needs science.
In order to be successful, science needs religion; in order to be practical, religion needs science.
Unfortunately, in discussions of the relationship between science and religion, we too often focus on the few areas in which they conflict. But this misses a great opportunity. By combining technological advances with moral authority, science and religion can work together to save the world.
[Ed. Note: Don't miss the other perspectives in this Big Question series, from a Rabbi/M.D. and a Reverend/molecular geneticist.]