Experimental assessment of wood as a lightweight proton-radiation shield for spacecraft structures

• Wood specimens assessed as proton shields via 2D-IC mapping and multi-layer Faraday cup (MLFC) peak fitting. • Quercus & Betula schmidtii match 2 mm Al shielding with 5 mm wood panels. • Results support lightweight, debris-free wooden CubeSat structures for LEO missions. Wooden satellites are currently under development owing to their lighter weight, better processability, and lower manufacturing costs compared with conventional metallic constructs. Additionally, wooden satellites are inherently capable of autogenous deorbit burn-up after completing the mission. Therefore, wooden satellites are proposed to mitigate orbital waste. However, there is a general lack of research and knowledge on the space radiation shielding characteristics of wood, compared with conventional materials used in satellite structural manufacturing. Space radiation is an essential factor to consider in satellite system design, and energetic ions can markedly impair or destroy onboard electronics. To evaluate the radiation shielding properties of wood, 10 species underwent proton beam irradiation. The experimental results demonstrated that the two species effectively attenuated ionizing particles. Furthermore, the radiation energy degradation rate was quantified for wood and aluminum shielding to demonstrate suitability for space applications.