When astronauts become farmers: Harvesting food on the moon and Mars

With renewed interest in sending people back to the moon and on to Mars, thanks to NASA’s Artemis missions, thoughts have naturally turned to how to feed astronauts traveling to those deep space destinations. Simply shipping food to future lunar bases and Mars colonies would be impractically expensive. 

Astronauts will, on top of everything else, have to become farmers.

Of course, since neither the moon nor Mars has a proper atmosphere, running surface water, moderate temperatures or even proper soil, farming on those two celestial bodies will be more difficult than on Earth. Fortunately, a lot of smart, imaginative people are working on the problem.

NASA has been studying how to grow plants in space on the International Space Station for years. The idea is to supplement astronauts’ diets with fresh fruits and vegetables grown in microgravity using artificial lighting. Future space stations and long-duration space missions will carry gardens with them.

Growing food on the moon and Mars is somewhat different. A gravity field and a day/night cycle (of a sort for the moon) exist on each of those worlds. NASA, in partnership with several private organizations, is studying how to set up greenhouses at future lunar and Martian settlements.

Recently, NASA awarded $2.3 million in 11 grants distributed to 10 institutions to study how food crops could be grown in lunar regolith. The grants were distributed as part of the space agency’s Thrive in DEep Space (TIDES) program. Because of Project Artemis, NASA is eager to find ways for future lunar explorers to grow their own food.

In the meantime, the China Agricultural University has already grown plants in a lunar soil simulant treated with three kinds of bacteria. Lunar soil by itself, since it lacks water and organic matter, is infertile, meaning that any attempt to grow anything in it would fail. The Chinese researchers achieved some success growing Benth plants in the lunar soil simulant treated with the bacteria, but more research is needed before lunar settlers can start farming.

Starting farms on Mars is another matter. Most people have seen the film “The Martian,” in which the main character, Mark Watney, grows potatoes in Martian soil treated with human waste. But what research is being done to grow food for future Martian settlers?

According to Arizona State University, Martian soil is contaminated with the chemical perchlorate. Food grown in such soil, left untreated, would be dangerous for humans to consume. Anca Delgado, a professor of environmental engineering at ASU, is studying adding microorganisms to Martian soil that process the perchlorate into nontoxic byproducts. As a bonus, the microbes will provide carbon to the soil that will enable seed germination.

For future explorers to plant crops in the soils of the moon and Mars, these extraterrestrial greenhouses will have to be enclosed, controlled environments. A group called GrowMars, founded by Dr. Daniel Tompkins, believes that it has come upon part of a solution using bioplastic created by algae and the byproducts of plant and other waste created by lunar or Mars settlements combined with some source of energy. The plastic would be 3D printed into building material to build the greenhouses. The more bioplastic created, the larger the greenhouses become, and the more lunar or Martian settlers can be fed. As a bonus, the plants grown in the greenhouses turn the CO2 exhaled by the settlers into oxygen.

The GrowMars concept has some earthly applications, not only as a market for carbon dioxide captured from power plants or directly from the air but as enclosed farms located in inhospitable parts of the Earth, such as deserts and tundra. Tompkins recently discussed the concept at length on an episode of The Space Show podcast, GrowMars also received funding from NASA for a project called One Giant Leap for Life: Moon Demonstration Garden, with some support from Lockheed Martin.

When human civilization expands beyond the Earth to the moon, Mars and beyond, human space settlers will have to learn to live in their new homes without a long supply chain back to the home world. Researchers are already studying ways to grow abundant food so that a mining colony on the Moon or Mars settlements like Elon Musk hopes to build will be self-sustaining and thus thrive. The technology will almost certainly have benefits on Earth, as well.

Mark Whittington, who writes frequently about space policy, has published a political study of space exploration entitled Why is It So Hard to Go Back to the Moon? as well as The Moon, Mars and Beyond, and, most recently, Why is America Going Back to the Moon? He blogs at Curmudgeons Corner.  He is published in the Wall Street Journal, Forbes, The Hill, USA Today, the LA Times, and the Washington Post, among other venues.