LignoSat

Trash isn’t just a problem on Earth. Nearly 34,000 large pieces of debris, nearly 2,800 defunct satellites and millions of pieces of space trash are circling Earth’s orbit, according to European Space Agency. And that poses a real threat to the safety of astronauts and the viability of active satellites. Out to change that, Japanese logging firm Sumitomo Forestry and a team of Kyoto University astrophysical students are attempting to create the world’s first wooden satellite—which would at least leave less in the atmosphere. 

“We are very concerned with the fact that 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. Eventually, it will affect the environment of the Earth,” former astronaut and professor Takao Doi told the BBC.

Instead of all that metal, the LignoSat has a wooden shell designed to burn up upon re-entry. 

Branching off into wood solves another problem posed by metal-based satellite structures. It’s easier for radio waves to penetrate dried timber—allowing the team to place communication antennas and sensor technology directly into the body of the satellite. 

To create wood that can stand up to the dramatic temperature shifts and sunlight that come with traveling in orbit, Sumitomo R&D is working on a wood composite with complex polymers that demonstrate tensile strength and high compressibility. The big selling points? The materials are both inexpensive and abundant, and the manufacturing process can be automated. 

Once Sumitomo develops the right material mix, the Kyoto University team will test the woods in extreme environments on Earth that mimic those found in orbit. Then it will move to developing a flight model for testing and ultimately a 2023 launch.

Sumitomo is angling for another big business benefit from the project: The company plans to use insights gained from the satellite to help it develop materials for what would be the world’s tallest wooden skyscraper in Tokyo by 2041.