Newly outlined missions in the Vision for U.S. Space Exploration include extended human habitation on Mars. During these missions, large amounts of waste materials will be generated in solid, liquid and gaseous form. Returning these wastes to Earth will be extremely costly, and increase the opportunity for back contamination. Therefore, it is advantageous to investigate the potential for wastes to remain on Mars after mission completion. Untreated, these wastes are a reservoir of live/dead organisms and molecules considered “biomarkers” (i.e., indicators of life). If released to the planetary surface, these materials can potentially interfere with exobiology studies, disrupt any existent martian ecology and pose human safety concerns. Waste Management (WM) systems must therefore be specifically designed to control release of problematic materials both during the active phase of the mission, and for any specified post-mission duration. Likewise, WM systems must thoroughly address potential back contamination issues.
To effectively develop WM requirements and compliant technologies for Mars human missions, Planetary Protection (PP) guidelines must first be established. While previous policies for Apollo lunar missions exist, it is anticipated that the increased probability of finding evidence of life on Mars, as well as the lengthy mission durations will initially lead to more conservative PP measures. Development of these regulations requires a thorough understanding of anticipated waste streams, potential contamination pathways and mitigation operations.
This paper provides background regarding PP and WM issues, and investigates their potential interactions. Important topic areas are identified that require further research and/or development by both the PP and WM communities to ensure adequate WM system design for crew health and safety and both forward (Mars) and back (Earth) contamination control.