A team of researchers from the Japanese space agency, JAXA, wants to send a wooden satellite into Earth’s orbit. The idea is not as crazy as one might think. Visionary researchers behind the project, at Kyoto University, started from the conclusions of a recent test aboard the International Space Station (ISS), which exposed different types of wood to the vacuum of space. The result is surprising. Wood is remarkably resistant even in the complex space environment.
LignoSat Space Wood Project
“The space environment is extreme. Materials are subjected to temperature fluctuations, exposure to intense cosmic rays, and dangerous solar particles. Despite these adversities, the tests have confirmed the absence of decomposition or deformations, cracks, flaking, or damage to the surface after 10 months of exposure” Kyoto University recently stated.
Preliminary experiment is part of the LignoSat Space Wood Project, an international partnership led by Kyoto University. The university has already designed a wooden satellite, scheduled for joint launch by JAXA and NASA next year.
Project started in April 2020 as a collaboration between Kyoto University and Sumitomo Forestry. “The wood’s ability to withstand the conditions of low Earth orbit (LEO) has astonished us” said Koji Murata, head of space wood research, in a 2021 press release (ref.). “We want to see if we can accurately estimate the effects of the harsh LEO environment on organic materials”.
Test and Environmental Benefits
To test these effects, a small panel containing three different wood samples was brought to the ISS for storage in the Japanese experimental module Kibo. The samples were exposed to space for ten months in 2022. The wooden panel was retrieved by JAXA astronaut Koichi Wakata and returned to Earth aboard SpaceX‘s Dragon CRS-26 cargo spacecraft in January 2023.
Among the three tested woods, the LignoSat team chose to proceed using magnolia tree wood. The reasons lie in its “relatively high workability, dimensional stability, and overall strength” according to the statement.
If wood were to become a viable alternative for satellite production, it would offer several potential advantages over metal alloys used. Firstly, it is a more environmentally friendly material. It is easier to obtain, cheaper, and cleaner to produce. Furthermore, it is completely biodegradable, a fundamental aspect when considering the life cycle of a satellite.
When satellites are deorbited, the components usually burn up in the Earth’s atmosphere. The parts that do not burn are strategically deorbited to crash into remote parts of the ocean. In contrast, wooden satellites would burn up completely during atmospheric reentry.