The image of humans living on Mars has never been closest to becoming a reality.
The discovery that the red planet has liquid water and lakes – along with the rise of companies looking to explore it (such as Elon Musk’s SpaceX) – has lead to increasing discussion about colonizing Mars.
Although Elon Musk wants to get humans on Mars before 2030, NASA has a more conservative perspective. A colony is “a long way down the road,” according to Ben Bussey, a chief exploration scientist at the space agency.
Until then, scientists are already exploring answers to the question: how could we feed a human colony on Mars? In a recent study, researchers from the University of Central Florida analyze the resources and strategies needed to feed a Martian colony that increases to 1 million people within 100 years.
As you’d expect, the challenges are enormous – but technology may help overcome them.
Growing food on Mars – an astronomical challenge
Mars has no native flora or fauna, little solar radiation, an average temperature of -64º Celsius, and an atmosphere with around 95% CO2 and almost no oxygen.
How do you grow food in such an inhospitable environment? First, Mars settlers will have to let go of the idea of a conventional diet. They should focus on growing high-yield crops and gene-edited crops that can adapt to the higher CO2, according to the researchers.
Although recent movies about humans on Mars show greenhouses on the planet’s surface, the truth is, that method may not be the most efficient. That’s because greenhouses would take up a lot of space and need a lot of artificial light, at a high energy cost.
“An attractive alternative is to grow plants in tunnels with high-strength LED lighting, supplemented with sunlight collected and piped down through fiber optic cables,” the authors suggest.
Soil or no soil, that is the question
Martian soil poses another obstacle since it has no organic matter. This means inhabitants will have to compare the benefits of growing plants in soil-less systems (such as hydroponics) versus transforming martian soil into fertile soil. How? By fertilizing it with a nutrient solution, removing toxic perchlorates, and adjusting its physical texture.
“This effort could be started immediately by the first people on the surface, then scaled to produce large amounts of living soil needed for crop growth,” the study authors claim.
But which crops should people grow on Mars to ensure both food self-sufficiency and a healthy diet?
The Martian diet: insets and lab-grown meat
High-calorie, high-yield per area unit, and macronutrient rich: these are the characteristics of the best crops to grow on the red planet.
Certain specific crops stand out for the authors – corn, wheat, and sweet potatoes for carbohydrates, soybeans for protein, and peanuts for fats.
Of course, these foods aren’t enough to feed a human population. Animal protein, for instance, is a type of food most people can’t forego. Given the difficult logistics of animal farming in Mars, insects and lab-grown meat will have to fulfill the need for animal protein.
Insects will be especially important. They require little space, water, feed, and maintenance, but produce high yields and have good caloric and nutritional content. On Earth, insects are mostly niche, but “in a martian economy [they] may become a much more important industry.”
For the insect-averse, cellular agriculture – A.K.A. lab-grown meat – will be a more appealing alternative. This consists of harvesting cells from an animal and then multiplying them in a laboratory.
Cellular agriculture makes it possible to create burgers, fish or even eggs and milk from just a few animal cells. (Lab-grown meat isn’t available on Earth yet, but the first commercial launch should happen before early 2020).
The advantages of cellular agriculture for a Mars colony are obvious: in comparison to conventional methods, it offers “significantly more calories produced per units of water and land.”
At the end of the day, growing and selling food products on Mars will account for 5 to 10% of Martian GDP. Clients would not only be permanent immigrants, but also tourists and astronauts on exploration missions.
For many, these projections may look like a science fiction movie. But, as they say, truth is stranger than fiction.