Eating on Mars Will Be Complicated and Cold
The physics and chemistry of cooking and agriculture will be toppled on the Red Planet.
Michele Perchonok has, like nearly all of us, spent her whole life on Earth. But she constantly thinks about what it will be like to live on Mars.
“The picture I always use in my mind is that you launch from Earth, and you see the planet getting smaller and smaller, and you realize you will not see Earth at that size for another two-and-a-half to three years,” she told The Daily Beast.
Perchonok, however, doesn’t think about the journey to Mars as much as she thinks about what will happen after we finally land, and what we’ll eat.
A food scientist by trade and the current president of the Institute of Food Technologies, Perchonok previously spent 17 years at NASA’s Johnson Space Center in Houston as the Advanced Food Technology Project Manager and the Shuttle Food System Manager, overseeing the direction of the agency’s food program and the development of what it chooses to feed astronauts living and working in low Earth orbit.
The challenge isn’t just to produce a menu for space dwellers. It must account for myriad problems—which can get tricky when solutions conflict with one another. “We can’t develop a food system as a silo, for any mission for NASA,” said Perchonok. “[Food] affects everything else.”
The first major issue with food in space has to do with delivery. Human food wasn’t meant to be floating around weightlessly in a cold vacuum outside our atmosphere.
“There are challenges at NASA that you wouldn’t consider anywhere else,” Perchonok said. “One of those is mass and volume.” Every single cubic inch inside a spacecraft needs to be heated and pressurized, and doing so takes an enormous amount of energy.
Because that internal space is so valuable, it’s critical that astronaut food occupies as little of it as possible—using half a spacecraft as a giant walk-in pantry would be egregiously inefficient. Items must be compact and packaged tightly, like TV dinners.
Shelf-life is another consideration—there’s still no way to grow or make food in space. We’re forced to send packages from Earth. The rockets that carry those supplies are expensive to make and launch, so new food packages can only be sent once in a while, and must stay fresh for a minimum of several months.
The design and engineering of space food is, in fact, a multidisciplinary endeavor, integrating the biochemistry of food compounds, the chemistry and materials science of packaging and preservation, and the physics of how space environments transform and modify.
The fact that the journey to Mars will take six months complicates the already difficult juggling act of food delivery and storage in space.
For one, how do you cook in space? Voyagers will have to prepare a meal in microgravity with limited kitchen tools. In addition, there will be dietary restrictions and preferences (a good meal can go a long way to making life in a stressful environment—like hurtling through space in a gravity-free tube— a lot more bearable).
Then there’s shelf-life. “Shelf-life for food is really a combination of the environment it’s stored in, the packaging, the ingredients and how they are processed,” among other things, Perchonok said.
Then there’s the problem of refrigeration. One might think the vacuum of space or the sub-zero temperatures on Mars would naturally refrigerate food, but such low temperatures would irrevocably distort the cell structure of the food and the packaging itself. Storing food outside of a spacecraft or habitat would also create the hurdle of suiting up to reel those packages in at meal time.
This creates what Perchonok calls a “matrix” of a problem. Concocting a new type of starch that keeps foods preserved at higher temperatures is possible, but limits what kind of food we could have. Artificial refrigeration within the spacecraft might be possible, but the insulation and energy required would be impractical.
“You can’t put yourself in a bubble,” Perchonok said. “Chemistry is happening in that package, and as time passes, you’re losing nutrients and food quality. You have to make sure those things last from the beginning of the mission to the end.”
Eventually, however, we want to start farming on Mars. The first few missions will probably rely exclusively on packaged foods, resembling what astronauts already eat on the International Space Station, imbued with longer shelf-lives.
But, “as the level of missions progresses, I think you’ll see more progression into growing plants,” Perchonok said. The larger goal will be to use agriculture to creating a sustainable food system that lets future Martian colonists grow what they need on the Red Planet itself.
So what exactly will we be farming on Mars? Wheat and soy will probably still be off the table for a while (and brought over to Mars in bulk), since these foods take a lot of time to process into edible foods. But fear not, bread-lovers: NASA is already testing how viable it is to grow certain forms like dwarf wheat in space, which could lead the way to eventually growing such plants in larger agriculture habitats on Mars.
Fruits and vegetables, on the other hand, are largely ready for consumption once they grow large enough and ripen on their own time. Perchonok thinks we’ll see fresh fruits and vegetables being grown on Mars by new colonists soon after they land. A single type of agricultural habitat could be employed to grow all kinds of different plants, with modifications to temperature and moisture applied as necessary.
Scientists are already experimenting with growing vegetables like lettuce in space and microgravity environments, with a surprising amount of success (with some trial and error along the way). Future experiments will be aimed at testing the viability of growing and harvesting tomatoes on the space station as well. The 2015 movie The Martian popularized the idea of growing potatoes on the red planet, and while we’ve yet to try this, some scientists in Peru have demonstrated that potatoes could grow in Mars-like conditions, which is encouraging.
The advent of technology also means the possibility of growing cultured meat on the red planet, enjoying a bite of steak that’s been brewed in a lab.
“My understanding is right now, it is nowhere close to being resource-efficient,” Perchonok said. It would take too much time and space and energy to grow even something minimal. One company’s production costs, for example, still hover to just a little below $2,400 per pound of artificial meat. “[But] I have heard through the grapevine that the industry believes we’ll have this fixed in 10 years,” she said. “We’ll see.”
We might also develop viable aquaculture systems to grow fish on Mars. The work on this is extremely preliminary and fraught with difficulties: the ISS already operates a specialized fish tank (courtesy the Japanese Space Agency) to study how a school of medaka fish get along in space, and microgravity doesn’t seem to suit their fishy bodies.
But if those kinks can be worked out and we can create a habitat that’s easy to maintain, then fish like tilapia might prove the best candidates for life on Mars, thanks to their high nutritional value and protein content. In fact, fish might be an exceptional solution to preventing astronauts from experiencing bone loss in low-gravity environments.
Sourcing foods is one problem, but cooking is an entirely different beast. Part of the reason TV dinners have worked so well for astronauts so far is that they require extremely little preparation, apart from heating and maybe a dash of hot sauce to counteract the dulling of the taste buds in space.
On Mars, however, people are going to want to cook good meals for themselves, their colleagues, and their families. It’s human.
“Even cooking a pasta dish, you’re going to need some sort of stovetop,” said Perchonok. “You need pots and pans and big spoons and tools, and you need to boil water.” There will also be a big concern for conserving resources as effectively as possible—if you mess up a dish, there won’t necessarily be enough water or heat to make a new one.
No one has much of a clue what this is supposed to look like on Mars, where gravity is one-third what it is on Earth. How does boiled water on Mars behave? Does it splash around too much, or is it able to stay grounded enough to soften up the pasta well? Does the pasta itself maintain its structure as it warms up in the water? Will the sauce you’re using maintain the sort of consistency you’re looking for? Will any oils or spices you use mix in well enough? Will microgravity make it difficult to transfer things from one bowl to another? Will it distort how wet or how dry we keep certain things? Answering these questions will be a scientific process in its own right.
“We just don’t know how much the Martian gravity will change these things,” said Perchonok. “It’s exciting to ponder these things for the future, but they’ll also take a lot more study and testing to really understand.”