Trash or Treasure? Results of Integrated Waste Trade Studies for Moon-to-Mars Missions

NASA’s Logistics Reduction technology development project has been analyzing waste products from human spaceflight and innovating ways to turn the trash burden into resource treasures. Reducing, reusing, and recycling waste products can be a win-win proposition if solutions for waste disposal can also supplement the supply of materials needed in space habitats. The trade studies described here sought to match the most appropriate waste processing technologies to many of the missions envisioned in NASA’s Moon-to-Mars architecture. Waste processing technologies being developed by NASA and partner companies were evaluated against current waste disposal notions for lunar surface missions of 30 to 365 days and a Mars transit mission of 850 days round trip. The technologies assessed include trash compaction and trash-to-gas as well as other technologies that can process human metabolic waste, plant waste, and plastic waste. The integrated life support and waste disposal systems were analyzed using an equivalent system mass technique to compare mass, volume, power, and cooling of the relevant systems with and without waste processing, resulting in an estimate of launch mass savings for the different missions. Other considerations discussed include mission factors such as life support system closure, planetary protection, radiation shielding, trash storage volume, odor, and sustainability.