Challenges and Opportunities for Construction of a Lunar Ark, a BioRepository for Earth’s Bio-Diversity

The lunar lava tubes are a network of nearly 100 subsurface tunnel-like tubes formed from ancient lava flow on the Moon’s surface. They can provide a great shelter that is impervious to cataclysmic changes that occur periodically on Earth’s surface. The lunar lava tubes are expected to be a shelter from the extreme temperature variations of the Moon’s surface, as well as solar and cosmic radiation, in addition to micro-meteorites. Earlier, our team envisioned utilizing one of the lunar lava tubes, which are nearly 80 m in cross-sectional diameter and nearly 100 m deep as Earth’s biorepository (Lunar Ark). The Ark would cryogenically store eggs, sperm, seeds, and spores from 6.7 million species of plants, animals, and fungi. In this paper, we analyze the challenges and opportunities to construct a subsurface Ark on the Moon. In developing this Lunar Ark, we envision having to build a facility that can readily expand further into the lunar lava tube as needs increase. We envision the Lunar Ark to consist of a series of cryogenically frozen cylindrical that are assembled in-situ on the bed of a lunar lava tube. The pre-fabricated cryo-compartments loaded with the bio-matter would arrive from Earth using a Starship-type lander. Once each compartment is laid end to end, they would be connected by passageways to enable robotic vehicles to seek and fetch small containers containing bio-mater from each species (in the form of standard cassettes), and they would be brought up to the surface for further examination. The main challenge is to construct most, if not all, of the facility on the surface of the Moon or elsewhere and position it into place in a lunar lava tube. Further, given that the lava tubes are 2-4 billion years old, we would need to take stringent measures to preserve and protect them by building a greenenvironmentally friendly structure that would minimize footprint and, most importantly, not damage the walls and ceilings of the ancient lunar lava tubes. This paper analyzes the system components of the Lunar Ark construction. We first envision developing an inflatable membrane that would be expanded into the lava tubes, creating a protective shell. Next, a series of three parallel raised mono-rail systems will be built to transfer in and on-out heavy goods into the lava tubes. The monorails will be anchored using a regular series of support structures mounted to the base of the lava tube. The rail system would be used to construct, expand, and perform large-scale servicing of the Lunar Ark compartments. Further, once delivered to the Moon, the compartments need to be always under cryo-conditions and switch from internal cryo-cooling to using the facilities cryo-cooling facilities. First, the support structure to permit movement of the compartments will be constructed, followed by driving in rail robots that perform hauling and moving tasks much like a gantry crane. The compartment will be moved into place from the service rail line to the construction/assembly rail line and parked in an available spot on the base structure. The compartment will switch over from using its own internal power to maintaining cryo-temperatures using the facility's power generators. Utilizing this system of construction which we have briefly presented here, will permit us to build and expand the Ark as needed while working to best preserve the lunar lava tube features. Importantly, we look to the rapid construction and setup so the Lunar Ark becomes operational in a matter of days with the delivery of the cryogenically preserved content to the surface of the Moon.