发表机构
Pioneer Labs（先锋实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出PRIM框架，通过单应激源传播测定评估火星生物ISRU微生物的前向污染风险，使活体生物在低水活度和碳饥饿条件下即使高生物负载也能通过飞行认证，支持火星持续存在。
AI 中文摘要
NASA的行星保护政策旨在避免太空探索过程中对天体的意外前向污染以及地球的后向污染。对于火星任务，该政策历来侧重于着陆器和巡视器的灭菌处理。当前政策并未为那些有意包含活体生物且不得进行灭菌的任务（如载人乘组、农业或用于制造和生命维持的生物技术）提供前向污染风险评估框架。我们提出了PRIM（传播受限，火星惰性）框架，用于评估已知生物体所构成的前向污染风险。基于生物封存文献和污染概率模型，PRIM通过独立的单应激源传播测定，将生物体在火星表面从最坏情况的非名义事件中释放后持续生长的能力限制在概率P_c ≤ 10^-4以下。我们将PRIM框架应用于两种工程化的火星生物原位资源利用（bio-ISRU）底盘生物体，利用低水活度和碳饥饿条件，使其即使在高生物负载下也能被认定为低前向污染风险，并概述了如何将测定方法扩展到光养生物和厌氧生物。PRIM提供了一条基于实验室测定而非仅凭生物负载来对火星活体生物进行飞行认证的途径。这使得在火星上持续存在所需的生物生命维持基础设施成为可能，同时将前向污染风险保持在可证明的低水平。
英文摘要
NASA planetary protection policy seeks to avoid inadvertent forward contamination of celestial bodies and backward contamination of Earth during space exploration. For Mars missions, it has historically focused on sterilization of landers and rovers. Current policy provides no framework for assessing the forward contamination risk of missions that deliberately include living organisms and must not be sterilized, such as a human crew, agriculture, or biotechnology for manufacturing and life support. We propose the PRIM (Propagation Restricted, Inert on Mars) framework to evaluate the forward-contamination risk posed by known organisms. Building on the biocontainment literature and probability-of-contamination model, PRIM bounds the ability of an organism released from a worst-case off-nominal event to sustain growth on the Martian surface at a probability under P_c <= 10^-4 using independent single-stressor propagation assays. We apply the PRIM framework to two engineered Mars biological in situ resource utilization (bio-ISRU) chassis organisms, using low water activity and carbon starvation to qualify them for low forward contamination risk even at high bioburden, and outline how to extend the assays to phototrophs and anaerobes. PRIM offers a path to flight-qualify living organisms for Mars based on laboratory assays rather than bioburden alone. This enables biological life support infrastructure for a sustained presence on Mars while keeping forward contamination risk demonstrably low.
