Increased interest and investment in space exploration are driving efforts to develop the technologies needed to make the moon a viable home for humans. Developing lunar infrastructure requires building materials which would be costly and inefficient to launch from Earth. This has led to research into the in-situ processing and use of raw materials naturally found on the Moon's surface. One major challenge with this approach will be the huge amount of power that lunar resource processing will need.
Lunar regolith is the moon's top layer of soil and dust. A research team from the University of Waterloo's Laboratory for Emerging Energy Research (LEER) is looking into processing regolith into usable materials for life support, energy generation and construction. This research includes investigating the use of defunct satellite material as a fuel source when mixed with lunar regolith. The International Astronautical Federation has published two papers on the regolith research.
Connor MacRobbie is a Ph.D. candidate who is supervised by professors Dr. John Wen and Dr. Jean-Pierre Hickey in Waterloo's Department of Mechanical and Mechatronics Engineering. He said, “Lunar regolith contains lots of metallic dust embedded with oxygen. Because it already contains oxygen, we can utilize it, without the need for atmospheric oxygen, to produce thermal energy. This is called a thermite reaction, which is useful in space because there is no readily available oxygen.”
The LEER team carried out experiments using simulated “lunar” regolith synthesized and supplied by the National Aeronautics and Space Administration agency (NASA). Tests were performed on different fuel and oxidizer compositions and with varying particle sizes to regulate the energy release rate of a space-based thermite for either heating or manufacturing.
Wen, who is the director of LEER, said, “The results demonstrate the viability of the moon's topsoil to power lunar development, enabling humans to explore and inhabit the moon's surface. We're now continuously working at better extraction of metal and other useful material from the regolith as well as designing automated processes, in collaborations with Canadian and international researchers, to facilitate in-situ resource utilization and support the circular space economy.”
A potential threat to humanity's future travels in space is the millions of bits of fast-moving debris that exist between Earth and the Moon's orbits. The European Space Agency (ESA) compares a collision with a one-centimeter particle of space debris traveling at 10km/s to that of a small car crashing at 40 km/h. The LEER research team is working to deal with this problem by recycling defunct satellite material into a fuel source for space development.
MacRobbie said, “Defunct satellites have enormous potential value. They're made up of many useful materials, including aluminum, which, when added to lunar regolith, can produce a thermite reaction and generate heat.”
Using the thermite reaction to repurpose salvaged space debris can also provide materials for developing and maintaining solar satellite systems in space, ensuring power for further space exploration.
MacRobbie added that “Our research is turning science fiction into reality. Our goal is to help build the infrastructure and technology that will allow sustainable human settlement on the moon—and beyond.”