Farming on the Final Frontier: Space Farming with Martian Soil Simulants

Abstract

Because temperature and light intensity on Mars are significantly lower than that of Earth, the use of controlled environment agriculture production to grow crops can be an option. The objective of this study was to compare simulated Martian soils Mojave Mars Simulant (MMS-1) and Enhanced Mojave Mars Simulant (MMS-2) to a commercial growing medium, Pro-Mix BX Mycorrhizae (Pro-Mix), based on overall plant growth, health, and edible end products. The Martian soil simulants, MMS-1 and MMS-2, are composed of crushed Saddleback Basalt rock. MMS-2 differs due to the addition of nutrients and oxides. In this study, we looked at a variety of crops chosen for their nutritional value, cold and shade tolerance, and size. Crops were dwarf curled kale, ‘Red Robin’ tomato, and ‘Cherry Belle’ radish. Mars is further from the Sun than Earth resulting in lower light intensity and colder climate. To simulate this, a shadehouse and fans were used to diffuse sunlight and regulate temperature. To explore this idea further the crops in the soils were examined under full-spectrum light-emitting diode (LED) grow lights indoors on a 16-hour day length timer. Plant height and stem diameter taken on a weekly basis showed delayed rates of growth in all crops with both MMS-1 and MMS-2 compared to Pro-Mix. Edible end products were not significantly different in the compared soils. From these experiments, it was found that additional nutrients provided through a pellet fertilizer or nutrient solution are necessary for proper plant development when using the Martian soil simulants.