Hoping to reduce space debris, Japanese researchers have designed the world’s first wooden satellite. Its recent launch aboard a SpaceX rocket is a feat that could usher in a new era of eco-friendly satellites for future interstellar travel.
Does the very first wooden satellite portend a new generation of satellites made from renewable materials? This is the stated ambition of the researchers at Kyoto University who designed this innovation in partnership with Sumitomo Forestry¹. This experimental wooden satellite was successfully launched on November 5, according to the New York Times, aboard a SpaceX Falcon 9 rocket from NASA’s Kennedy Space Center in Florida as part of a resupply mission. of the International Space Station. Called LignoSat²it has been chartered to the space station and will be put into orbit in a month about 400 km above Earth. Over six months, the strength and durability of the satellite will be evaluated in space to test whether it has the potential required to replace traditional metal satellites.
Fight against space pollution
The conquest of space goes hand in hand with the creation of metallic particles which pollute space. These correspond to space debris from satellites at the end of their life. Indeed, when they are decommissioned, satellites are deviated from their orbit and reach the atmosphere where they burn up to avoid becoming space debris. However, the metallic constitution of the satellites generates aluminum oxide particles. This debris can accumulate in space and cause collisions with satellites held in their orbit at very high speeds. Each collision in turn generates additional debris; This chain reaction is known as Kessler syndrome³. In addition, this space debris can reach our terrestrial environment. Last May, a farmer discovered a 2 meter wide space debris in his field. The use of wood as a material offers the advantage of complete disintegration without the emission of toxic residues during the satellite’s atmospheric reentry. This less pollution makes LignoSat a prototype of a biodegradable satellite. The absence of water and oxygen in the space prevents the wood from rotting or burning.
Overcoming the technological challenges posed by a wooden satellite
The wood used for this satellite comes from a species of magnolia native to Japan: honoki. While traditionally used for sword scabbards, this wood was chosen for its lightness and resistance to the highly rigorous conditions of the space environment. Being designed using a traditional Japanese craft technique, without screws or glue, the satellite is expected to suffer complete destruction upon its return to Earth. LignoSat takes the form of a compact box with each side measuring barely 10 centimeters; metal electronic components surround the wooden structure. Once deployed, LignoSat will be put into orbit and tested in real conditions using sensors collecting data relating to the physical behavior of wood in this extreme environment. The satellite will, in fact, be subjected to cosmic radiation with solar particles which can degrade electronic components, temperatures being able to oscillate between -100°C and 100°C every 45 minutes depending on the position of the satellite in relation to the sun .
Wood, the future ally of satellites?
Contrary to popular belief, wood can become a material of choice when it comes to innovation in the technological field. Koji Murata, professor of forestry sciences at Kyoto University, recalls that planes were made of wood at the beginning of the 20th century. The use of this material could revitalize the wood industry. Designers are considering banning metal satellites in the near future and are even imagining extending the use of wood for other space infrastructures such as lunar or Martian bases.
[1] Japanese company specializing in wooden construction
[2] In reference to the Latin word meaning “wood”
[3] Increasingly rapid increase in the number of space debris in Earth orbit following collisions between space objects generating, at a rate higher than that of their natural elimination, new debris
