In 2026, NASA’s Artemis program will send astronauts to the moon after five decades. Plans for later phases include setting up a space station orbiting the moon and a permanent base on the lunar south pole. Producing food on-site will be essential for long-term space travel. It would allow space missions to take off with far less weight, which lowers fuel usage and eliminates the need for resupply missions. 

However, producing food in space is incredibly difficult. There is very limited space aboard spacecraft, and microgravity impacts the growth of plants and cells in space. Previous attempts at growing food in space have been proofs of concept. Astronauts at the International Space Station (ISS) still largely rely on food deliveries from Earth. Now, advances in synthetic biology are improving the feasibility of growing food in space.

Growing Food in Space

Astronauts have grown lettuce, mustard, and bok choi, although in small quantities, on Veggie, a vegetable garden on the ISS. A significant challenge with growing crops for regular consumption in space is that they take up a lot of room. Gene editing plants to optimize their architecture could deal with this limitation.

For example, “researchers can build different form factors, making plants smaller and dwarf-like so they could grow in more confined spaces,” said Adam Arkin, professor of bioengineering at UC Berkeley. Changing the chlorophyll composition of leaves reduces shading and allows for denser growth. Moreover, engineering plants for photosynthetic efficiency increases their biomass yield. 

Researchers are engineering plants to make them more resilient to the stresses of space. How ?? Plants have benefits beyond nutrition. They are versatile and can be engineered to produce medicines, transform carbon dioxide into oxygen, and help recreate the biospheric condition. Additionally, like people living in apartments, astronauts find having plants around mentally stimulating. 

As compared to plants, microbes are relatively easier to grow and more amenable to bioengineering. This makes them a more adaptable approach to producing food in space. “Imagine being on a flight, needing to change something about your food, you could change them more quickly,” said Arkin.

Yeast has been engineered to produce a wide variety of food ingredients and pharmaceuticals and is viable in space. “The bonus is yeast is inherently very nutritious. It meets a lot of the nutritional requirements specified by NASA on its own,” said Lancia Lefebvre, founder of AstroYeast, a student-led initiative to engineer controlled production of nutrients in yeast.

Typically, nudging yeast to express a gene and produce an ingredient requires chemical inducers. “But in space, we don't want to send more chemicals,” said Lefebvre. Instead, AstroYeast uses light-induced gene expression, which could toggle between producing different nutrients. A satellite carrying AstroYeast’s engineered yeast will be launched into space in 2025 or 2026 under the CUBICS Initiative of the Canadian Space Agency.

A shortcoming of yeast, however, is that it is heterotrophic. It needs feedstock that must be carried to space. “While the autotrophic microbes we use require less feedstocks since they can generally use atmospheric carbon dioxide and light to grow, the microbes we use, like spirulina, taste like armpits and are hard to engineer,” said Arkin. His research group is trying to make spirulina, an algae popular as a dietary supplement, more palatable and more engineerable for nutrient, pharmaceutical, food, and advanced bioplastic production applications.

More recently, synthetic biology companies are exploring cellular agriculture to produce space food. The technology makes alternatives for dairy, meat, leather, and other animal products by culturing cells in controlled environments. “Cultivators maintain a controlled, sterile environment where cells thrive, nourished by a carefully formulated cell feed containing water, oxygen, nutrients, and growth factors,” said Yoav Reisler, marketing communications director at Israeli biotech Aleph Farms.

Under optimal conditions, cells multiply rapidly. Aleph Farms uses a plant protein matrix made of soy and wheat to coax these cells into a three-dimensional structure that replicates real meat.

Other researchers are experimenting with mushrooms and insects, among other systems, to produce food for space more efficiently. The different approaches to producing space food are not competing but complementary. 

Resource-Efficient Food Production

When astronauts set up camp on the lunar or Martian surface, synthetic biology will be a key enabler. In addition to food, they would need to fabricate drugs, building materials, and fuel. Engineered microbes and plants can extract vital elements required to make these materials from alien surfaces and atmospheres. Over longer timescales, engineered microbes could terraform their surfaces to make them similar to Earth. 

Meanwhile, biological manufacturing for space needs to be self-sustaining and flexible. The same apparatus should be deployable to produce diverse foods and other essentials. This flexibility, Arkin said, would allow dealing with the unknown unknowns in space travel.

Companies are developing food production platforms that support resource-efficient food production and waste management. “We are recreating controlled environment systems, closed loop structures where an AI autonomously recreates any type of conditions,” said Barbara Belvisi, CEO of French-American biotech Interstellar Lab. The company’s platform supports the growth of any plant species—including gene-edited ones—and insects for food.

“It can adapt to the nutritional food gaps you want to cover,” added Belvisi. Whether there is a more pertinent need for protein, vitamin C, or potassium, the system can pivot to produce it. Belvisi added that gene-edited plants could make it easier to produce specific nutrients.

Plants in space have to deal with microgravity. It disrupts plant growth and development, and can both increase or decrease yields under different conditions. Growing plants in controlled environments mitigates these effects, but research is still underway to underpin its mechanisms. Optimized lighting systems could also improve yields. “We are exploring the possibility of having lights all around so plants will spread, and instead of growing tall, they will grow wider,” said Belvisi.

Under microgravity, yeast cells in suspension culture are evenly suspended, which improves their yields. On the contrary, microgravity is a challenge to culturing animal cells for cellular agriculture. “Changes occur in cell size, shape, adhesion properties, and key processes such as differentiation and programmed cell death,” said Reisler. Aleph Farms’ technology overcomes it with closed-loop, resource-efficient production methods.

Even on Earth, cellular agriculture is hard to scale up. Aleph Farms is tackling this hurdle from two sides. “The first focuses on optimizing cell production through AI algorithms. The second application involves identifying cost-effective alternatives to expensive cell culture ingredients,” said Reisler. Scaling up might not be a barrier for early long-term space missions, however, because feeding few astronauts requires modest amounts of cell culture.

When astronauts spend extended periods in space, efficiency is only one of the considerations in food production. The food should meet different nutritional requirements and, if produced in yeast or via cellular agriculture, have a familiar taste and texture. Further advances in gene editing and bioprocessing technologies could meet these requirements. 

Insights for Food Production on Earth 

All technologies to produce food in space are vital if humans are to become a multi-planetary species. Firstly, it is to meet the different nutritional needs over a lengthy space mission. Secondly, a diverse set of food-producing organisms would be crucial to recreating a self-sufficient ecosystem, particularly for terraforming.

Lessons from trying to grow food in space could apply to agriculture in resource-constrained or climate-impacted areas on Earth. Innovations in growing space food with gene-edited plants and closed-loop production, for instance, yield insights that could apply to sustainable food production on Earth. 

Presently, the biggest constraint to advancing technologies to produce space food is the absence of a well-defined market. Space food is something that companies and space agencies will need in the future, but it is not something in demand now. Although the absence of an immediate market driver means everything is a bit theoretical, it has a benefit, too.

“It allows us to explore things that would be economically impossible to do industrially on Earth but have high value to our aspirations in space,” said Arkin. “And once we learn them, they're almost always translatable back to Earth application.”