MARS HABITAT – SURFACE MATERIALS ISRU Jean Bigoney Mars Sustainability Workshop - Buzz Aldrin Space Institute Feb 8-9 / 2018

The Essentials, Part 1 Materials seek a state of minimum energy Natural state of materials usually as oxides Some oxides are “easier” to extract the oxygen from than others This is going to steer us in the direction of using native oxides or being very selective about refining

Ellingham Diagram ∆G – Gibbs Free Energy of oxide formation describes stability of oxide. The lower the value of ∆G, the more stable the oxide, and the more energy required to separate metal from oxygen atoms.

Timeline of Metal Usage

Use of Materials in Habitats on Earth Classification Animal Skins - Vegetable Wood, Straw Wood Mineral Stone, Mud, Brick, Cement Stone, Mud, Brick, Cement, Glass, Lead Stone, Brick, Cement, Glass, Lead. Steel, Brass Stone, Brick, Cement, Glass, Lead. Steel, Brass, Aluminum, Gypsum, Plastic, Fiberglass, Silicon Oxide

Oxide Abundance on Mars vs Earth Brick: SiO2, Al2O3, FeO / Fe2O3 / Fe3O4, MgO, CaO Cement: SiO2, Al2O3, FeO / Fe2O3 / Fe3O4, MgO, CaO Glass: SiO2, Al2O3, FeO / Fe2O3 / Fe3O4, MgO, Na2O

The Essentials, Part 2 Despite 10,000 years of materials progress, we still use primarily oxide-based materials for habitats on earth Similar raw materials exist on Mars as on Earth which can be used to process into construction materials for habitats The most promising materials for construction on Mars will be brick, cement, mortar and glass.

The Challenge, Part 1 Do bricks, mortar, cement and glass fit in with the most promising concept for the structural design for habitat / regenerative life support systems? (need input from Habitat Design)

The Challenge, Part 2 Can indigenous materials be reliably identified, collected, and processed under conditions on Mars? (need input from Surface Materials, Manufacturing, Power Supply)

Summary Humans on Mars will not have it was easy as our ancestors on Earth. Indigenous materials are available on Mars which can be processed into familiar habitat construction materials. What and how we process will depend on what is needed and what is feasible. We need a method of identifying materials that will work reliably on Mars. We need a method of sorting and grinding that will work reliably on Mars.. We need a source of energy that will heat the raw materials to the desired process temperature.