Martian Soil Simulant Background

• Tom Carol from Aspect Science conducting experiment with 12 kilos of Martian soil simulant
• Previous research showed growing crops in Martian soil is "probably possible" with soil tweaking
• Martian soil contains all nutrients needed for plant growth but requires controlled indoor environment and liquid water supply
• No actual Martian soil samples returned to Earth yet (unlike moon samples)

Development of Martian Soil Simulants

• Early understanding from Viking and Pathfinder missions' orbiters, landers, and rovers
• NASA JPL developed JSC Mars-1 Martian soil simulant in 1998
• Original simulant used weathered volcanic ash from Mount Aquella, Hawaii
• Newer simulants developed when experiments showed original lacked certain Martian soil properties

Mojave Martian Simulant (MMS) Creation Process

• Provided by Martian Garden in Texas
• Uses basalt rock from ancient volcano in Western Mojave Desert
• Basalt is dark iron-rich volcanic rock - key ingredient of Martian surface
• Process: crush boulders → smaller particles → range from fine powder to gravel
• Sifted multiple times into coarse, fine, and superfine grades
• Missing toxic chlorates found in real Martian soil (lethal to crops and humans)

Experimental Setup

• Two germination pod trays, four columns:
  • Column 1: MMS with fertilizer
  • Column 2: MMS with nothing added
  • Column 3: Earth soil (comparison)
  • Column 4: Water retaining sheet only
• Four microgreen varieties: pea plants, sunflowers, cress, radish
• Microgreens chosen for quick/easy growth and early harvest capability

Germination Process Science

• Seeds initially dormant with stopped growth and metabolism
• Environmental cues trigger germination (heat, smoke for fire-prone areas)
• Imbibition: seeds absorb large amounts of water, expand, rupture outer coats
• Metabolic changes trigger enzymes to digest food stores
• Embryonic root emerges first for water access
• Shoot tip breaks through soil surface
• First true leaves develop for photosynthesis

Experimental Results

• Day 1-3: All seeds began germinating
• Mid-experiment observations:
  • Fertilized simulant plants performing poorly (likely over-fertilization)
  • MMS plants growing slower than Earth soil plants (expected result)
  • Clear differences visible between growing conditions
• Day 14: Harvest of microgreens completed

Agricultural Implications

• Real Martian soil nutrients may not be abundant or in accessible forms
• Requires tweaking with micro/macroscopic organisms and fertilizers
• Need to ensure proper nutrient availability and cycles for sustainable use
• Research by Dr. V Guevara at Wageningen University successfully grew tomatoes, carrots, green beans, and potatoes in Martian soil simulant

Future Applications

• Current research prepares for eventual Mars settlement (decades away)
• Could improve agricultural practices on Earth
• Focus on determining starting point and necessary modifications rather than simple seed-to-plant growth