Scientists warn of space pollution because many of these satellites become inactive over time and turn into waste. It is this observation that pushed Japanese engineers to develop a wooden satellite. It could be launched in 2024.
There are currently more than 8,000 satellites orbiting the Earth above our heads.
They are used to improve communication, to spy or to better observe climatic phenomena. But space must not become a trash bin, and on Tuesday October 3, for the first time in the world, an operator was fined $150,000 for not having “not properly desorbed” one of its satellites.
To avoid the transformation of these satellites that have become inactive into waste, Japanese engineers are banking on the development of a wooden satellite, the first prototype of which could be put into orbit in 2024.
In wood, but not just any wood
Engineers at Kyoto University have been studying this concept for years. They do not work alone and benefit from the expertise of carpenters and joiners. Particularly craftsmen who usually work on the restoration of old Shinto temples or on the repair of old samurai costumes.
Engineers needed them to identify the wood species most resistant to extreme conditions. They found three interesting woods and samples were sent to the International Space Station last year for several months of testing.
The wood that seems to best resist sudden temperature changes, solar particles and cosmic rays is a Japanese magnolia. This wood did not warp, it did not crack, it did not chip. The satellite will therefore be made of magnolia.
A very small object of extreme precision
This revolutionary object will be called LignoSat and is very small. You have to imagine a cube with a side of 10 cm. The walls, usually made of metal, will therefore be made of wood. They will fit together with extreme precision. We are talking about a margin of error of 0.01 millimeter.
Inside will take place the classic measuring or communication instruments, with electronic components and normal electronic circuits. What is targeted is not this content but the end of life of the satellites which rotate in low orbit around the Earth.
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These satellites all normally have a mission and a predetermined lifespan. Then they plunge toward Earth and burn up in the atmosphere. But they do not burn 100% and leave lots of tiny particles in the air, notably the aluminum in the walls, which contributes to air pollution.
With wooden satellites, combustion will be complete. When they return to Earth, their combustion will be better and will leave much less waste. This is the bet of Japanese scientists who will launch this first wooden satellite next year from an American rocket.