In-Situ Radioisotope Sterilization for Backward and Forward Contamination - Enabling low-mass, Low-Complexity Solutions for Planetary Protection

The quest to protect planetary bodies from contamination by Earth life and to shield Earth from potential extraterrestrial life forms is a critical concern for NASA's planetary science missions. The Mars Sample Return and other decadal missions targeting the icy moons of the outer solar system are flagship missions prioritized by NASA. However, they face significant cost and complexity issues from stringent planetary protection needs. Current planetary protection measures involve complex sterilization processes, redundant seal containments, lengthy quarantines, power, and special handling procedures, all adding significant mass and cost to the missions. Our proposal introduces a paradigm-shifting radioisotope-based sterilization system. Unlike traditional methods that use heat or chemicals, which can damage samples and leave residues, this innovative technology utilizes primary ionizing radiation to sterilize nucleic acids (DNA and RNA) and prions without affecting the bulk material. This method is particularly advantageous for long-duration missions, as it allows for sterilization over the extended return trip from Earth (forward contamination) and returning from Earth (backward contamination). The long duration allows for a low-activity, low hazard radiation source. This approach provides a low-mass, low-complexity, low-cost solution for robust planetary protection. In addition, our sterilization techniques can target multiple types of radioisotopes, which can be used either to sterilize a surface or a volume based on the type and energy of radiation. This technology would add a new tool to the planetary protection toolbox and help NASA and emerging commercial companies comply with planetary protection rules at a low cost and minimal impact on conops.

This technology has direct applicability as NASA is actively considering many sample return missions (Mars) and missions in general to locations where life may exist (Mars, Icy Moons, etc.). In many cases, NASA incurs significant costs to prevent forward or backward contamination. Scientists are excited for sample return missions throughout the solar system. Locations such as Mars and the icy moons of the outer planets are prime candidates in the search for life. However, care must be taken to protect Earth’s environment from the potential risk of bringing that life back to Earth (backward contamination) and ensure that Earth life is sterilized and cannot affect potential ecosystems on other planets. Forward and backward contamination between planetary bodies is a paramount challenge for sample return missions. To prevent the biological transfer of possible extraterrestrial microbes, strict rules for planetary protection exist (see NASA’s NPR 8715.24). Complex sterilization, redundant seal containments, lengthy quarantines, special handling, and mission ConOps are the current state of the art for planetary protection. Mars Sample Return results in additional mass for the sample return containers, chemical- and heat-based sterilization systems, and ground facilities. Each link in the chain of sample return is consequently heavier and more expensive. This technology offers NASA an additional tool for achieving planetary protection and can significantly simplify a mission architecture, saving cost and providing assurance of meeting planetary protection requirements. Beyond NASA, many other space agencies, such as ESA, JAXA, ISRO, and even non-state groups such as the Planetary Society, are interested in searching for life in the Solar System. This technology would apply to any mission planned to locations that could bear life and would be especially applicable for sample return missions, regardless of whether the intent was scientific or commercial in nature. The Outer Space Treaty requires space exploration to "avoid harmful contamination" of celestial bodies and adverse changes to Earth’s environment from extraterrestrial matter. The COSPAR Planetary Protection Policy, recently restructured in March 2024, is the primary international framework for preventing biological contamination during space exploration. While COSPAR is not technically legally binding, it clarifies the binding Outer Space Treaty’s Article IX (preventing harmful contamination) and Article VI (state responsibility for compliance) ensuring missions do not compromise the search for extraterrestrial life (forward) and prevent Earth contamination from returned samples (backward) An effective and cheap method of providing planetary protection would enable all civil, space, and commercial actors to comply with the rules clearly. We believe there is significant commercial potential here. If life were to be found in the solar system, this technology's commercial and scientific value would be compounded.

This is a mature technology (TRL 7+) — the realistic path in is usually NASA's Technology Transfer Program: licensing an existing NASA patent, or a Space Act Agreement to use NASA facilities/expertise directly. NASA also runs a startup licensing program with no upfront fee for companies formed to commercialize a specific NASA technology.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.