A groundbreaking international initiative, spearheaded by Kyoto University, has successfully conducted a pioneering experiment to assess the durability of wood in space at the renowned International Space Station (ISS). The findings from this project have not only confirmed the exceptional resilience of wood in the extreme conditions of space but have also highlighted its suitability for the construction of the innovative wooden satellite, LignoSat.
In order to comprehensively evaluate the performance of wood in space, the research team embarked on a meticulous series of examinations. These included rigorous tests to assess strength, as well as detailed analyses of elemental composition and crystal structure. Astronaut Koichi Wakata played a crucial role in collecting the wood samples during the SpaceX CRS-26 mission, which facilitated their safe return to Earth from the ISS.
The remarkable results obtained from the experiment unequivocally demonstrated the robustness and stability of the wood specimens. Despite enduring drastic temperature fluctuations, exposure to intense cosmic rays, and hazardous solar particles over a ten-month period, the wood exhibited no signs of decomposition, deformation (such as cracking, warping, peeling, or surface damage), or mass alteration.
To determine the most suitable wood for the forthcoming LignoSat mission, the research group carefully considered a range of factors. Ultimately, they identified Magnolia wood, commonly referred to as “Hoonoki” in Japanese, as the optimal choice. Magnolia possessed favorable attributes such as exceptional workability, dimensional stability, and overall strength.
The LignoStella Space Wood Project, a collaborative endeavor between Kyoto University and Sumitomo Forestry, commenced in April 2020. In 2022, the project achieved a significant milestone by subjecting wood samples to an extensive 290-day space exposure test within the Japanese Experiment Module Kibo of the ISS.
With preparations underway for the launch of the wooden artificial satellite in 2024, the research group is actively investigating the fundamental mechanisms underlying the degradation of materials at the nanoscale level. By gaining a deeper understanding of this phenomenon, they aim to develop robust wood materials that exhibit exceptional performance and can be utilized in a wide range of innovative applications.
Source: Kyoto University