The glass fibers in lunar regolith could help build structures on the Moon

With the Artemis program, NASA has been planning to send astronauts to the moon for more than 50 years. Before the decade expires, this program aims to create the infrastructure that will allow “a sustainable program of lunar exploration and development.” The European Space Agency (ESA) also has big plans, which include the creation of a lunar village that will serve as the spiritual successor to the International Space Station (ISS). China and Roscosmos also met in June 2021 to announce that they will build the International Lunar Research Station (ILRS) around the lunar south pole.

In all cases, space agencies plan to harvest local resources for construction needs and long-term needs—a process known as in situ resource utilization (ISRU). Based on samples brought back by the fifth mission of the Chinese Lunar Exploration Program (Chang’e-5), a team of researchers from the Chinese Academy of Sciences (CAS) has identified authentic fiberglass for the first time. According to the paper they authored, these fibers formed from past impacts in the region and could be an ideal building material for future moon bases.

The work was led by Rui Gao, Liquan Chen, Dongdong Xiao, and Zhao Zhang from the CAS Institute of Physics (IOP) in Beijing. They are joined by researchers from the University of the Chinese Academy of Sciences (UCAS) Center for Materials Science and Optoelectronics Engineering, Songshan Lake Materials Laboratory, Qian Xuesen Laboratory of Aerospace Technology, Chinese Academy of Aerospace Technology (CAST), and Nanjing University’s School of Engineering and Applied Sciences. team paper,” Varied glasses of Chang’E-5 have been revealed Lunar regolithRecently appeared in National Science Review.

As the IOP team points out in their paper, lunar glasses are an important component of lunar soil and are produced by various processes. In all, they identified five types based on the formation process involved: volcanism, impact, adhesion, deposition, and radiative. These glasses can remain stable for billions of years, providing a geological record of the Moon and leading to a better understanding of its formation and evolution. This includes questions regarding the duration of volcanic activity, late heavy bombardment, the origins of lunar water, and the presence of a lunar magnetic field.

The team determined that impacts are the most active processes on the Moon, because they are “highly heterogeneous on both a temporal and spatial scale” — that is, impacts are an ongoing phenomenon, unlike volcanism and other geological activity that ended billions of years ago. By studying the various glasses in 1.73 kg (3.8 lb) of lunar regolith that Chang’E-5 (CE-5) brought back from the northern mare Oceanus Procellarum, they were able to elucidate their origins and attribute them to three main mechanisms: impact, deposition, and radiation.

As they explain, the samples were very different from those brought back by the Apollo astronauts and the Soviet Luna program, suggesting different mechanisms are at work in Oceanus Procellarum: “Compared to earlier samples from Apollo and Luna which were limited to narrow volcanic ages of 3.9-3.0 Ga and covered Only about 4.4% of the lunar near surface, CE-5 samples are collected from the smallest dated lunar region at 2.0 Ga and the highest mean latitude, allowing the moon to be studied in an extended spatiotemporal scale.Preliminary characterizations show that CE-5 samples are Mature samples, but have a much lower glass content than the 8.3%-20.0% of the Apollo samples (25.4%-72.3%), implying a very different space environment than the Apollo sites.”

When characterizing the morphological, microstructure, and geochemical characteristics of the samples, the team found that the CE-5 samples contained different glassy textures. As shown in the image above, this included glass particles of various shapes, such as globules, ellipsoids, obliques, and tears (from A to I). They also noted the presence of elongated glass fibers (based on their elongations) that ranged in shape from tadpoles (n), mace (o), and whiskers (p). They also concluded that these fibers were formed from molten material from impacts that cooled in contact with the lunar environment.

These fibers would make a highly effective building material, consistent with proposals to build lunar bases through the ISRU. The IOP team indicated this by tackling previous attempts to make synthetic glass fibers from lunar regolith mimics in the lab.

In short, their analysis showed that these fibers could be harvested on the moon and used to manufacture the necessary materials: “[Attempts were made using] Lunar simulation materials for the manufacture of synthetic fiberglass in laboratories for the construction of a future lunar base. Our findings demonstrate directly that fiberglass can be produced on site on the Moon, which may inspire space industrialization glass Fibers such as monolithic optical fibers and structural fiber reinforcement required by future lunar bases. ”

Before space agencies can build long-term habitats on the Moon, research characterizing the Moon’s environment and resources is absolutely necessary. In addition to providing new insight into the many processes that formed The surface of the moon Over time, studying IOP could provide a path toward establishing permanent bases on the moon. This research can also inform future missions to Mars, which NASA and China plan to begin by 2033. These missions include the creation of surface habitats, and further characterization of the Martian environment could lead to specialized construction methods.