Expanding Astrobiology: The Case for a Lunar Biorepository

INTRODUCTION

Earth’s resources—life, materials, energy, water, and food—support our expansion to work in and explore space. As we plan these new ventures, Earth’s ecosystems and natural resources are being compromised by overextraction of terrestrial and marine assets, natural disasters such as fires and extreme weather events, and socioeconomic threats, such as wars.^1,2 These events threaten Earth’s biodiversity and the integrity of essential ecosystems. ³ Innovative strategies are needed urgently to conserve Earth’s biodiversity and protect fragile ecosystems. One such strategy is the development of biorepositories in space, which could significantly expand the scope of astrobiology. Toward that end, we recently proposed a passive Lunar Biorepository ⁴ to safely hold cryopreserved samples from some of the most critical species on Earth for extremely long durations, potentially centuries or more. Our goal is to broaden NASA’s current definition of astrobiology: “NASA’s Astrobiology Program investigates life in the universe on many levels: how it began, how it evolved here on Earth, and where it might exist elsewhere.” ⁵

Briefly, our previous work ⁴ described the concept of a Lunar Biorepository based on passive cryogenic storage at the lunar south pole as a safeguard for Earth’s biodiversity. It also supported the scientific reasoning behind the idea, using cells of a fish (the starry goby) as a proof-of-concept, and identifying two initial technical challenges (radiation damage and maintaining liquid nitrogen temperatures). It concluded with an open call for collaboration. This perspective work builds on that foundation through four additional concepts: (1) the Lunar Biorepository should be encompassed within the framework of NASA Astrobiology as a cross-cutting astrobiological capability rather than solely a conservation tool; (2) it advances several details of the concept, including specific site-selection criteria for Permanently Shadowed Regions (PSRs), novel construction approaches using lunar regolith, and a multipurpose cryogenic payload system design; (3) it broadens the scientific scope to potentially support astrobiology and long-duration crewed spaceflights; and (4) it outlines a community-building and governance strategy across academic, commercial, and nonprofit sectors.

A Lunar Biorepository is a cross-cutting concept that can help redefine and expand astrobiology’s role in both space exploration and Earth conservation. This effort would parallel the Svalbard Global Seed Vault. ⁶ That passive biorepository requires little maintenance staff or energy yet holds a backup supply of Earth’s most important agricultural seeds in case of a catastrophic collapse of crops. Seeds are maintained at Svalbard at −18°C. ⁶ This is much warmer than the temperature required to cryopreserve living animal cells, −196°C, a temperature not naturally sustained on Earth. Instead, these cryopreserved species could be stored in the south pole of the Moon in areas, such as PSRs,^7,8 that remain at or below liquid nitrogen temperatures indefinitely. Moreover, on Earth, major biorepositories, even those with cryopreserved collections, are often near large coastal population centers and vulnerable to threats, such as climate change and political instability, whereas a biorepository on the Moon would be protected from climate change, but not necessarily political instability as attention to the Moon grows over time.

The Lunar Biorepository would initially store cryopreserved fibroblast cells. These powerful cells are recognized for their dynamic and multifaceted roles in various biological processes, including tissue repair, immune modulation, and even cancer progression. ⁹ Fibroblasts can potentially be transformed into induced pluripotent stem cells that can be further differentiated into spermatozoa and oocytes. ¹⁰ When thawed, these cells can be used to generate whole organisms. ¹⁰ Furthermore, the Lunar Biorepository could store biomaterials for food, filtration, microbial breakdown, and ecosystem engineering for extraterrestrial endeavors. Residing under approximately eight to ten meters of regolith to help reduce the effects of radiation, ¹¹ these cryopreserved samples could remain frozen-and-alive for centuries. They could be returned to Earth, as needed, to help bolster animal, plant, or microbial populations as well as be leveraged for environmental conditioning of the planetary environment.

A Lunar Biorepository will not only advance our understanding of life in space but also serve as a valuable and achievable driving goal that benefits life on Earth and humanity in the form of an archive of biological samples and genomes from key species. This archive can serve as a resource for biotechnology and innovation and as a hedge against ecological disaster and species diversity loss on Earth. The disciplinary backgrounds and expertise of our initial team are substantial. Yet the decades-long efforts to bring a Lunar Biorepository into full operation will require an even fuller set of collaborators from broad sectors, including academic, commercial, and nonprofit. For example, collaborative decisions about which species and their supporting web of species are selected will take time and consideration. Some of this has already been accomplished by groups such as the Earth Biogenome Project, which has a goal to collect and sequence 1.6 million species in the next 10 years. ¹² They have spent 15 years developing metrics for species selection and acquiring permits to make collections.^12,13 We plan to partner with such groups rather than reinvent processes.

Astrobiology as a scientific discipline is broadly defined as the study of the origin, evolution, distribution, and future of life in the universe. NASA’s Astrobiology Program operationalizes this definition through a specific set of funded priorities focused primarily on the detection of life and biosignatures beyond Earth and the study of life’s limits in extreme environments. While the Lunar Biorepository is consistent with the broader scientific definition of astrobiology, it does not yet fit comfortably within the current programmatic scope. We argue here that expanding that scope to encompass the preservation of Earth’s biodiversity as an astrobiological resource is both scientifically justified and necessary and that doing so strengthens rather than dilutes the intellectual coherence of the field.

As stated previously, NASA Astrobiology’s current programmatic scope centers on the origins of life, the limits of life in extreme environments, and the search for life and biosignatures elsewhere in the solar system and universe. Biodiversity preservation and the cryogenic archiving of Earth’s species have not been included within this scope, not because they are scientifically unrelated, but because they represent an application of astrobiological knowledge, namely the application of cryobiology and biosignature science to conservation, which has not yet been formally recognized by the program. We propose that this recognition is overdue. Expanding the programmatic scope of astrobiology to encompass the Lunar Biorepository concept would not redirect existing mission priorities; it would create a new category of cross-cutting astrobiological capability with direct relevance to space exploration, long-duration human spaceflight, and planetary sustainability. Achieving this programmatic recognition is one practical goal of this article, but the intellectual case for the expansion stands independently of any possible future funding outcome.

The Lunar Biorepository will help maintain Earth’s most important species while providing critical assets to explore and work in space. As we embark on long-duration space missions and begin to explore or inhabit other planets, human populations will need the capacity to feed themselves in their local environment.

GOALS AND BENEFITS OF A LUNAR BIOREPOSITORY FOR ASTROBIOLOGY

This perspective piece has three distinct scholarly aims: (1) to argue that the concept of a Lunar Biorepository legitimately and meaningfully expands the scope of astrobiology, both conceptually and practically; (2) to describe the science and engineering needed to realize this concept, identifying where foundational work has been done and where critical gaps remain; and (3) to call on the broader astrobiology and space science community to engage with this interdisciplinary challenge.

We propose that the scope of astrobiology should be expanded to encompass the following: (1) the science of long-term biological preservation in extreme space environments, including cryopreservation and the behavior of biosignatures under conditions of extreme cold, radiation, and microgravity; (2) the study of Earth’s biodiversity as an archive of evolutionary solutions to survival under diverse and extreme conditions, directly relevant to questions about the nature and resilience of life; and (3) the application of biological resources to sustain long-duration human spaceflight and support planetary habitability research. A Lunar Biorepository would serve all three of these functions simultaneously, making it a genuinely cross-cutting astrobiological capability. This expanded framing does not depart from astrobiology’s foundational commitment to understanding life in the universe; it deepens it by recognizing that preserving the life we already know is itself an astrobiological act with profound implications for science and exploration.

DISCUSSION

There are challenges in “securing Earth’s biodiversity and supporting human exploration and terraforming of other planets [through] long-term storage on the Moon. ⁴ ” Yet the benefits to astrobiology of a Lunar Biorepository are many. It will: (1) provide a testbed for cryopreserving organic and biological materials in space environments which will inform theories of material transfer between planetary bodies, their detection as biosignatures and aid in the development of technologies for long-term preservation of biological material for biosignature recovery for robotic missions and long-duration crewed spaceflight; (2) maintain cryopreserved cells to be transported to-and-from the Moon, allowing cryopreserved samples from the Moon to travel safely to Earth, for example, frozen water on the Moon may be transported to Earth for study; (3) help maintain healthy Earth Ecosystems because it is a hedge against extinctions on Earth; (4) be cost-effective, because it will preserve biodiversity and genetic diversity of thousands of species in a passive biorepository with a small footprint on the Moon; (5) advance studies comparing cellular and evolutionary processes in cryopreserved lunar cells with those processes in parallel samples on Earth to elucidate how cells respond to long-term holding in space, thus supporting biotechnology and innovation; (6) support space exploration (e.g., by providing a source for cells needed for planetary environments conditioning and food resources during extended flights and human habitation on the Moon); (7) leverage the strengths of the U.S. National Science Foundation’s NEON and the Smithsonian, among other institutions, for collecting cells, data management and acquisition, and cryo-storage; and (8) support the Earth and all humanity.

The challenges and the potential solutions for a Lunar Biorepository include: (1) radiation damage, which can be mitigated by barriers such as covering the biorepository with meters of regolith; (2) maintaining liquid nitrogen temperatures at all times for the samples, which can be offset by use of cryo-engines^24,25 during transit and centering our activities at the south pole of the Moon in or near PSRs ⁷ that have areas at liquid nitrogen temperatures year round; (3) the use of PSRs could be sensitive due to planetary protection concerns, but some areas, such as dry PSRs, that may maintain the same low temperature may be of less concern; they must be identified through international consultations; (4) microgravity may impact cells; little is known about the effect of microgravity on biological material once it is frozen; and (5) organizing, managing, and protecting a Lunar Biorepository from Earth will be an enormous challenge that will depend upon careful consideration of ownership and long-term governance issues, among many others.

We are ready to begin the next phases of discussion, planning, collection, testing, design, and importantly, collaboration across the interdisciplinary scientific community. Initially, we will use existing collection protocols to gather material for the biorepository, such as those for the NEON. ³⁰ We have identified robust space-proven packaging to hold the cryopreserved cells in stasis on the Moon ³¹ and have designed a payload with a space-proven cryo-engine^24,25 that can maintain the cells at cryopreserved temperatures from lift-off-to-landing on the Moon. We anticipate that much of the work to build and maintain the Lunar Biorepository could be accomplished through uncrewed spacecraft, assisted by rovers and robots. ³² Finally, this project is a way to evaluate preservation and retrieval mechanisms to return newly discovered life to Earth, which will have to travel great distances with minimal energy or human intervention. The passive aspects of the Lunar Biorepository could provide a testbed for future, distant retrievals.

Currently, the Lunar Biorepository concept does not fit within any existing NASA program, but this need for expansion is not unique. Several now-central areas of space science initially fell outside NASA programmatic boundaries before achieving recognition as legitimate research priorities. These include astrobiology, which was once considered too speculative for sustained investment; planetary protection was initially treated as an operational constraint rather than a scientific field; and finally, lunar resource utilization required decades of advocacy before it was formally incorporated into exploration planning. In each case, advocacy was needed to articulate the intellectual case, the building of an interdisciplinary community, and the demonstration of relevance to existing program goals. The Lunar Biorepository faces analogous challenges and opportunities.

We argue that a Lunar Biorepository represents a legitimate and important expansion of astrobiology’s disciplinary scope within the NASA community. NASA’s Astrobiology Program constitutes a community whose programmatic boundaries reflect historical decisions about which questions count as astrobiological. Those boundaries, shaped by networks of experts, have influenced how scientific priorities are created and have shifted before.^33,34 For example, the establishment of astrobiology as a recognized NASA program in the late 1990s itself required sustained boundary work: advocates had to argue that questions about the origin and distribution of life, previously scattered across geology, chemistry, and planetary science, constituted a coherent and fundable scientific field. The case for the Lunar Biorepository follows the same logic. We are not proposing to change what astrobiology studies; we are arguing that the preservation and study of Earth’s biodiversity in space environments is a natural extension of astrobiology’s existing intellectual commitments and that recognizing it as such serves both science and exploration.

As we look hundreds of years or more into the future, this biorepository can support many space missions and provide a hedge against species extinction on Earth. To support people and life beyond Earth, we must understand how life can exist in space and be transported to other regions. This biorepository is a major step toward creating the mechanism and the means to understand this process.

CONCLUSIONS

To support human life beyond Earth, we must first understand how life can exist in space and be transported to new environments. Developing a Lunar Biorepository offers valuable insights into astrobiological processes, especially in extreme environments like ocean worlds, which may be more common in the universe than are rocky planets such as Earth. Looking hundreds of years into the future, such a biorepository could support numerous space missions and may serve as an insurance policy against species extinction on Earth. For humans to undertake long-duration space travel and settle on other planets, we must be able to grow food during space travel and within the local environment. A Lunar Biorepository, housing a diverse collection of cryopreserved seeds, cells, and microorganisms, would also provide these essential resources. Ultimately, establishing a Lunar Biorepository represents a crucial step toward enabling sustainable exploration and deepening our understanding of life beyond our planet.

AUTHORS’ CONTRIBUTIONS

M.H.: Conceptualization, funding acquisition, writing—original draft, writing—review and editing. L.R.P.: Conceptualization, funding acquisition, writing—original draft, and writing—review and editing. R.C.: Conceptualization and writing—original draft. P.C.: Conceptualization and writing—original draft. P.M.: Conceptualization, writing—original draft, and writing—review and editing. B.M.: Conceptualization and writing—original draft. S.W.: Conceptualization, writing—original draft, and writing—review and editing. J.B.: Conceptualization and writing—original draft. R.S.: Writing—original draft. S.N.T.: Writing—original draft. M.T.: Conceptualization and writing—original draft. B.J.: Conceptualization, writing—original draft, and writing—review and editing. R.A.: Conceptualization and G.F.: Conceptualization, writing—original draft, and writing—review and editing.