The world’s first wooden satellite was launched into space today, an early test of the use of timber in lunar and Mars exploration. This move paves the way for future SpaceX satellites to be made from wood rather than aluminium.
Known as the LignoSat probe, the world’s first biodegradable satellite was invented by Japanese scientists, who, combined with Japanese forest giant PEFC-certified Sumitomo Forestry, discovered that magnolia wood is the ideal alternative to earth-polluting metals used in satellites.
Named after the Latin word for “wood,” the palm-sized LignoSat is tasked with demonstrating the cosmic potential of renewable material as humans explore living in space.
“With timber, a material we can produce by ourselves, we will be able to build houses, live and work in space forever,” said Takao Doi, an astronaut who has flown on the Space Shuttle and studies human space activities at Kyoto University.
And with a 50-year plan to plant trees and build timber houses on the moon and Mars, Doi’s team decided to develop a NASA-certified wooden satellite to prove wood is a space-grade material.
“Early 1900s aeroplanes were made of wood,” said Kyoto University forest science professor Koji Murata. “A wooden satellite should be feasible, too.”
“Metal satellites might be banned in the future,” Professor Doi said. “If we can prove our first wooden satellite works, we want to pitch it to Elon Musk’s SpaceX.”
Research proves beyond doubt that exposed wood can survive in space.
Already, the material has been tested at the International Space Station, with Wood Central reporting in May that an international team of scientists led by Kyoto University in Japan proved beyond doubt that exposed wood showed negligible deterioration and maintained stability in space.
The push to use biodegradable materials in satellites comes as the global space industry looks for cleaner, greener and more sustainable materials amid a purge of space waste that is now littering the earth.
Wood Central understands that the launch now opens the door to replacing aluminium with timber, creating a space race for timber supply – more than 2,000 space satellites are expected to be launched annually over the coming decade.
“All the satellites which re-enter the Earth’s atmosphere burn and create tiny alumina particles, which will float in the upper atmosphere for many years,” according to Professor Doi, adding that “eventually, it will affect the environment of the Earth.”
To tackle the problem, researchers evaluated various species to determine how well they could withstand space launches and lengthy flights in orbit around the Earth.
The first tests were carried out in laboratories that recreated conditions in space, and wood samples were found to have suffered no measurable changes in mass or signs of decomposition or damage.
“Wood’s ability to withstand these conditions astounded us,” said Koji Murata, head of the project, with timber specimens then dispatched and texted at the International Space Station via the Japanese Experiment Module ‘Kibo.’
After a ten-month journey during which the specimens were subject to radical temperature fluctuations, cosmic radiation, and solar particles, astronaut Koichi Wakata of the Japan Aerospace Exploration Agency (JAXA) retrieved the samples.
Following their successful retrieval, SpaceX’s CRS-26 Commercial Resupply Service mission returned the specimens to Earth. Again, they showed little signs of damage, a phenomenon that Professor Murata attributed to the fact that there is no oxygen in space, which could cause wood to burn and no living creatures to cause it to rot.
“One of the missions of the satellite is to measure the deformation of the wooden structure in space. Wood is durable and stable in one direction but may be prone to dimensional changes and cracking in the other direction,” Professor Murata told the Observer.
Inside the LignoStat satellite
The LignoSat is made of honoki, using a traditional Japanese crafts technique without screws or glue. Once deployed, LignoSat will stay in orbit for six months. The electronic components onboard measure how wood endures the extreme environment of space, where temperatures fluctuate from -100 to 100 degrees Celsius every 45 minutes as it orbits from darkness to sunlight.
LignoSat will also gauge wood’s ability to reduce the impact of space radiation on semiconductors, making it useful for applications such as data centre construction, said Kenji Kariya, a manager at Sumitomo Forestry Tsukuba Research Institute.
“It may seem outdated, but wood is actually cutting-edge technology as civilisation heads to the moon and Mars,” he said. “Expansion to space could invigorate the timber industry.”
Why use wood in space?
Wood, particularly for small satellites known as CubeSats, has several benefits. “First, it eases the design process of satellites because it allows for the penetration of electromagnetic waves,” according to research published by Kyoto University last year.
This feature facilitates the internal positioning of components, such as antennas. Another critical advantage comes into play when a wooden satellite re-enters the Earth’s atmosphere. Unlike traditional metal satellites, which can release potentially harmful substances like alumina particles, a wooden satellite combusts entirely, preventing the release.
