Lunar Resources, Inc., a Houston-based company focused on large-scale industrialization of space, is teaming up with Wood, a consulting and engineering in Aberdeen, Scotland to study the Lunar South Pole Oxygen Pipeline (LSPoP), a pipeline at the south pole of the Moon.
"It is imperative for America to develop industrial infrastructure on the Moon to enable a permanent lunar presence. We are thrilled to team with Wood on the development of the LSPoP, [which] brings a premiere team to design revolutionary lunar infrastructure", said Elliot Carol, CEO of Lunar Resources.
Phase 1 Funding
The research is part of the NAIC phase one funding selection and is aimed at furthering the Artemis program and its goal of developing a permanent human presence on the Moon. A permanent presence is dependent on the ability to use in-situ resources because ferrying these resources from Earth would be far too expensive and dangerous. The extraction of oxygen on the Moon is essential for lunar operations. However, the transportation of oxygen is a major challenge.
Nasa’s current research efforts for in-situ oxygen extraction is focused on “bottling” the oxygen in compressed gas tanks or to liquefy and store it in dewars, which are insulated containers used for storing cryogens. Either approach requires moving tanks or dewars to various facilities for use. The process of moving this oxygen on rovers could be more energy intensive than the extraction process itself and could be the most expensive aspect of obtaining in-situ oxygen for use on the Moon.
"We estimate that the use of robotic rovers to transport gaseous oxygen in gas tanks would use more energy to transport the oxygen than extracting it," said Dr. Peter Curreri, Lunar Resources Chief Scientist.
The oxygen will be essential to supply human habitats, rovers and other life support systems with a constant supply of high purity oxygen. It will also be used as an oxidizer for launch vehicles departing the Moon. Oxygen extraction technologies are planned to be demonstrated at large scale on the Moon as early as 2024 and could provide direct support to Artemis astronauts as early as 2026.
Extracting oxygen ice and other lunar materials is one thing. Transporting it around a rock floating in space with no gravity or atmosphere is a much more complicated task.
For this design study, Lunar Resources and Wood will do a system-level design study of LSPoP. They will explore the feasibility of building pipeline elements on the Moon with the metals found there, which will be extracted using a process called molten regolith electrolysis (MRE). Lunar regolith is the unconsolidated sand-like debris on the surface of the Moon. Full scale test systems of this process on Earth have successfully extracted high-purity iron, aluminum and silicon.
The pipeline will be built using regolith additive manufacturing, which leverages Lunar Resources PE3D additive manufacturing technology to fabricate vertical and horizontal structures from lunar regolith without binding material. The program uses the PE3D low-average source power capabilities to efficiency additively manufacture regolith into complex structures with high density, low power and no consumables.
South Side of the Moon
In the submission for funding, which was posted on Nasa’s website, Curreri says the two companies will look at multiple system architectures for a lunar pipeline, identify enhancing and enabling technologies, and produce a comprehensive roadmap to develop the infrastructure.
The starting concept is for a 3.1-mile (five kilometer) pipeline to transport oxygen gas from an oxygen production source to an oxygen storage/liquification plant near a lunar base. L-SPoP will be composed of pipe segments that that will be manufactured, passivated and welded or fitted together onsite.
Based on preliminary analysis, Curreri says the in-situ pipe will be built in modular segments from in-situ aluminum, which is prevalent at the South Pole, is extractable in high purity with the proposed MRE process, can be directly extruded into pipe shape, and can be oxidized to passivate. Other in-situ metals which will also be analyzed for consideration include iron and magnesium, with a lunar glass passivation coating applied through vacuum deposition onto the internal diameter of the pipe.
He says this proposed modular design is adaptable, repairable, and evolvable because of the in-situ resource extraction and manufacturing techniques (with occasional system upgrades from Earth), resulting in a long life for the pipeline and lower cost and risk than other approaches.
The pipeline will be constructed robotically from regolith-derived metals with minimal material transferred from Earth. It will be repairable robotically and have an oxygen flow rate of ~2 kg/hour, which is commensurate with the NASA initial projected need of 10,000 kg/year. It’s expected to be able to operate with minimal power over the lifetime of the pipeline and have a high operational reliability with survivability in the lunar environment expected to be more than 10 years.
"To bring our pipeline expertise to the lunar surface is incredibly exciting for us, from both the potential impact this pipeline could have on lunar development and the technical challenges we must solve to implement a project this advanced," said Mark Netzel, Vice President, Onshore for Wood's Projects Business.