There are no supermarkets on Mars and deliveries from Earth will take several months. No matter how much food future astronauts bring with them on their journey to the Red Planet, they will inevitably have to buy it themselves in an inhospitable environment. It remains to be seen if they will take the imaginative path of farm-to-table with locally grown potatoes, as Matt Damon’s character did in 2015’s The Martian. But they may have an even more scientifically advanced alternative.
Making proteins out of air.
That’s the goal of a partnership between the European Space Agency and a company called Solar Foods, which emerged from a scientific research program less than a decade ago and opened its first large-scale production facility in 2024.
The project, called HOBI-WAN (for “bacteria that oxidize hydrogen in weightlessness as a food source”) in reference to the Star Wars movies, is a space version of a process that Solar Foods has already been working on here on Earth. In this experiment, bacteria are grown in a tank with water, air and nutrients, after which the bacteria are dried and turned into a protein powder. soleina for human consumption.
An important next step will be testing solar power generation on the International Space Station.
“Providing a nutritious and sustainable food supply that meets the crew’s energy needs is one of the most important challenges in human spaceflight exploration beyond low Earth orbit,” ESA said in a report. blog article. “In cases where pre-established food depots or continuous resupply missions from Earth are impractical, resource-intensive or technically impossible, cost-effective alternatives are needed.”
Produce protein powder from air
The central goal of the HOBI-WAN project is to discover whether the production of protein-rich powder can be carried out under microgravity conditions.
The process is complex, but it essentially lets nature take its course.
“Solar Foods produces solein through a process called gas fermentation,” said Arttu Luukanen, the company’s senior vice president for aerospace and defense. The gas fermentation process, he claims, creates single-celled organisms that feed on hydrogen and use it to “fix” carbon. From there, the bacteria receive “vital minerals”, such as ammonia, as a source of nitrogen and hydrogen.
All the ingredients, along with water and gases, are sent to a bioreactor with a pump, “a kind of big SodaStream,” says Luukanen. This gives bacteria an environment that promotes multiplication, which they can do very quickly. When the bacteria have multiplied enough, they are collected. A part is reserved for the next cycle in the bioreactor, while the rest is carefully dried and pasteurized.
These dried and pasteurized bacteria form the product Solein, which consists of 78% protein, 6% fat (largely unsaturated), 10% fiber, 2% carbohydrates and 4% minerals. Luukanen says that the powder can be flavored in many different ways and that it itself gives “a very mild umami taste.”
But can it also work in space?
Making electromagnets will be more difficult to accomplish in space. The weightless environment, limited payload and limited space for the bioreactor create additional challenges that ESA and Solar Foods believe they can solve.
“(The) main difference with the experiment on board the ISS is the absence of gravity, which means there is no buoyancy, which significantly changes the behavior of liquids and gases,” Luukanen explains. The second challenge is limited physical space. Solar Foods uses bioreactors that can hold 20,000 liters or more, while the bioreactor intended for the ISS will be significantly smaller: “several tens of liters.”
Additional steps are required in gas safety, process monitoring, quality assurance and maintainability, as there is no bioprocess engineer on board to monitor the process. Even products made in space are not reduced to dust, at least not on the ISS. In the event of a leak, it would not be ideal to have a cloud of dust floating in a weightless environment.
So solein is probably served in pasta form in space.
Reduce, reuse, recycle
The last important factor is the ingredients. They must be adapted to take into account the lack of resources available for long-duration space travel. Recycling has long played an important role in space life, and so has brine production.
This means using the CO2 breathed by the crew and reusing the hydrogen produced during electrolysis on the ISS. Converts water to oxygen. for the crew. On Earth, it takes a lot of water to produce brine.
Substitutions will also be made, for example by using urea instead of ammonia, as ammonia would be dangerous in an accident. But that doesn’t mean astronauts will use urine the way they do for “recycled coffee“.
“On Earth we use ammonia, but for the ESA project we decided to use synthetic urea, mainly because it is not as potentially dangerous as ammonia in the event of a leak,” explains Luukanen. “Recovering urea from urine is in principle possible, but given the small amount required, it may not be practical, especially if recovering urea from urine requires complex and heavy equipment.”
How long can this process last for astronauts?
A trip to Mars takes much longer than a trip to the Moon. NASA is coming our way Mission Artemis II Astronauts will orbit the moon for the first time in nearly half a century, but the journey will take just ten days. As for the food, it’s not that big of a deal. For missions like Escapade, true Two satellites will fly to MarsThe journey will take two years. On the way to the Red Planet, astronauts need to pack more than just a picnic.
If Project Solein was successful, the amount of food it produces could theoretically feed a team of astronauts for hundreds of days with far less cargo space than current space meals. Luukanen says that when the project was conceived, the astronauts only needed to carry mineral salts and didn’t need much of it.
“Even with a crew of five and a 900-day mission to Mars, we’re talking about (less than) 100 kilograms of mineral salts,” he says.
Other techniques can also help recycle nitrogen and minerals, allowing astronauts to reuse these materials in the field, further improving the food supply.
Protein powder made it possible for astronauts to cook all kinds of food with the right additional ingredients. Luukanen said Solar Foods has developed recipes ranging from ice cream to cream cheese ravioli. A number of these were presented below NASA’s Deep Space Food Challengewhich highlighted methods for long-term food solutions, including a light-free food growing method called Nolux and a closed ecosystem that can autonomously grow food and feed insects for an astronaut’s diet.
It might not be what you’d expect from a Michelin-starred restaurant or even a neighborhood shop, but it’s probably better than a steady diet of fried potatoes grown on Mars.