JOURNEY TO THE RED PLANET
Finding Ways to Feed the Future
By Jade L. Sherwood
As life continues here on Earth, the National Aeronautics and Space Administration (NASA) and SpaceX have announced their plans to further explorations deeper into space than we have ever been before.
NASA is planning its first manned trip to the Red Planet (Mars) to take flight somewhere in the 2030s. A round trip has been estimated to take roughly four and a half years allowing for six months of exploration on its surface prior to returning home.
To sustain proper nutrition and health to those aboard these long-term missions, and perhaps to those wishing to inhabit the planet in the near future, it is essential that cultivation techniques specialized for space travel be practiced to provide temporary residents with a proactive solution for consumption needs.
For decades, orbiters, landers and rovers have been preparing us for further exploration by collecting samples from the Red Planet itself, as well as atmospheric and radiation data to further our knowledge for potential population expansion. The data collected has presented us with the knowledge that Mars’ surface structure appears to be covered in crushed volcanic rock, with carbon dioxide, a semi-nitrogen atmosphere, and some presence of frozen water. While the ability to grow plants on Mars’ surface would be ideal to provide food for potential inhabitants, the Red Planet possesses many obstacles limiting plant production including soil conditions, atmospheric conditions and the ability to recycle wastes.
Here on Earth we are blessed with abundant soil containing a mixture of minerals, organic matter, gases, liquids and countless organisms; whereas, Mars’ decrepit soil, regolith, lacks organic matter and any known lifeforms to optimize soil performance. Chemicals called perchlorates have been identified in Mars’ soil—chemicals known to be toxic to humans. A concern for researchers is whether these chemicals present in the soil will be systemically absorbed by the plants.
“Martian soil simulant” taken from Pu’u Nene, Hawaii, closely resembles spectral soil from light regions on Mars, making it a perfect replicate to be used here on Earth. Currently, combined efforts between NASA and Florida Tech Space Aldrin Institute are conducting ongoing plant heath research with this simulant. Tests completed growing lettuce in soil simulant alone found that vegetation grew, but with a fail germination rate of ½ of seeds planted, slower germination period of an extended 3 days and weaker roots compared to potted soil samples.
Manure, fertilizer and worms were added to similar studies growing arugula in simulant soil. Researchers observed, “The positive effect of adding manure was not unexpected, but we were surprised that it makes Mars’ simulant soil outperform Earth’s silver sand.” Worms were found to thrive and produce additional offspring in Martian simulant soil providing hope for those wishing to add biological aid to Mars’ soil in the near future.
NASA’s organic waste recycling concepts, the Bio-regenerative Life Support System (BLSS) and the Closed/Controlled Ecological Life Support System (CLSS), have been developed to replicate Earth’s vast biological systems in space. Currently assisting those aboard the International Space Station (ISS) NASA’s plant growth unit, Veggie, is conducting ongoing space gardening and space plant biology research in orbit.
Along with vegetable production to sustain proper nutrition, the Mars’ mission will consist of vitamins, dried food, water, and equipment for plant growth systems. The successful growing of 10 crops in simulated Mars environments (tomato, rye, radish, peas, leek, spinach, garden rocket, cress, quinoa and chives) provides many options as NASA only wants to grow about 5 crops, making long-term nutritional complications a concern.
For crops to withstand Mars’ atmospheric conditions underground locations have been suggested. Mars only receives 60% of light compared to Earth therefore LED lights will be used regardless of orientation. Low-gravity environments also induce higher root zone processing in plants which requires a higher quantity of water and nutrients. To extract nitrogen from Mars’ atmosphere to increase vegetative growth, Bugbee explains, “We will look into inoculating plants with rhizobia like legumes to help them fix nitrogen.” Additionally Mars’ limited weathering means soil grains may not be broken down as much compared to earth. Soil grains may have sharper edges which could harm earth worms’ digestive tracts.
Closed material systems, BLSS, will be used alongside hydroponic units to implement biological and physicochemical technologies for the breakdown and conversion of waste products into useful additives for plants. The recycling of organic wastes, crop residues, skin cells, etc. through biological or physicochemical ammonification and nitrification are all solutions to make nitrogen re-available for food production. The use of worms (mealworms, silkworms and earthworms) to break down organic inedible wastes and for the consumption of additional protein has also been proposed. Single-cell proteins including microalgae, bacteria, and unicellular fungi are a high resource for ingestible proteins—microbial biomass being the highest at 50-70% protein combined with vitamins, pigments and prebiotic potential compounds. High-quality proteins also suggested include worms, fish, fungi and microbial materials.
The current BLSS concept being used at the European Space Agency (ASA), Micro-Ecological Life Support System Alternative, takes processed organic wastes to ferment, inhibit and maximize the formation of volatile fatty acids aiding in the further breakdown of carbohydrates. Low salt diets have also been proposed to dilute high salt concentrations in urine for the ease of processing for the use of irrigation water for plant systems.
Research developed to sustain basic human consumption needs in space could benefit our own planet, expand our current knowledge of agriculture and be of great value to the cultivation of crops here on earth. In the words of Bruce Bugbee, “When conducting research, you discover many things you weren’t intentionally looking for.”
Bedord, L. (2017). Farming in Space. Successful Farming. Agriculture.com. Retrieved January 8, 2018 from https://www.agriculture.com/technology/crop-management/farming-in-space
Dunbar, B. (2017). National Aeronautics and Space Administration; Journey to Mars Overview. https://www.nasa.gov/content/journey-to-mars-overview
Gruyter, D. (2017). How Plants are grown beyond Earth. Phys.org. https://phys.org/news/2017-03-grown-earth.html
Heiney, A. (2016). Farming in ‘Martian Gardens’. Journey to Mars; NASA’s Kennedy Space Center. https://www.nasa.gov/feature/farming-in-martian-gardens
Macdonald, F. (2016). Tomatoes, Peas and Eight other Crops have been grown in Mars Equivalent Soil. Science Alert. https://www.sciencealert.com/tomatoes-peas-and-8-other-crops-have-been-grown-in-mars-equivalent-soil
Science Direct. (2017). Nitrogen cycling in Bio regenerative Life Support Systems: Challenges for Waste Refinery and Food Production Processes. Progress in Aerospace Sciences, 7, 87-98. https://doi.org/10.1016/j.paerosci.2017.04.002
Starr, M. (2017). Research Shows that Earthworms can Thrive even in Mars Soil: Space woms FTW. Science Alert. https://www.sciencealert.com/earthworms-can-reproduce-in-fertilised-mars-soil-simulant
Tabor, A. (2017). Designing Future Human Space Exploration on Hawaii’s Lava Field. Journey to Mars; NASA’s Ames Research Center. https://www.nasa.gov/feature/ames/designing-future-human-space-exploration-on-hawaii-s-lava-fields