Japanese scientists sent wooden satellite to space: we want to pitch it to SpaceX

The world’s first wooden satellite has been sent to space to prove that wood is a space-grade material, and, most importantly, biodegradable.

After reaching the International Space Station (ISS), the four-inch wooden satellite named LignoSat will be released into orbit about 400 km (250 miles) above the Earth for a six-month-long test run.

Scientists will test how well wood withstands harsh space conditions, including extreme temperature shifts from -100 to 100 degrees Celsius every 45 minutes as the satellite moves from darkness to sunlight. They will also study wood’s potential to shield semiconductors from space radiation.

"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, a Japanese astronaut and engineer who studies human space activities at Kyoto University, told Reuters.

Current research might contribute to the future search for suitable and renewable materials to build houses in space. Scientists believe that wood may be more durable in space than on Earth, as there is no water or oxygen to cause rot or fire.

"It may seem outdated, but wood is actually cutting-edge technology as civilization heads to the moon and Mars. Expansion to space could invigorate the timber industry," added Kenji Kariya, a manager at Sumitomo Forestry Tsukuba Research Institute.

Magnolia is the best fit for the job

The research team worked extensively to identify the most suitable wood for the job. Erman’s birch, Japanese cherry, and a type of magnolia known as the honoki tree were among the short-listed candidates.

After being brought to the ISS in 2020, the honoki tree demonstrated the most strength and was picked by scientists to build LignoSat. The satellite was made using a traditional Japanese crafts technique without screws or glue.

"Early 1900s airplanes were made of wood. A wooden satellite should be feasible, too," said Kyoto University forest science professor Koji Murata.

The creators expect the wooden material to burn up entirely upon re-entering the atmosphere. The burning wooden satellite will only produce biodegradable ash.

More satellites – more garbage

Biodegradable wooden satellites might be the answer to the rising concerns of space debris, as they have minimal environmental impact at the end of their lives. "Metal satellites might be banned in the future," Doi said.

"If we can prove our first wooden satellite works, we want to pitch it to Elon Musk's SpaceX."

Regulating the life cycles of satellites has become extremely important with the rising number launched into orbit. Over the last twenty years, the number of satellites in orbit has increased 22 times and nearly tripled in the previous four years, reaching 10,247.

Elon Musk plans to have up to 42,000 Starlink over the next few decades, with the Chinese planning to have 14,000. Another issue is their short lifespan – for example, a Starlink satellite is usable only for five years.

Increasing traffic adds to the amount of garbage in the orbit that piles up from the old satellites and the clouds of satellite parts that form after the collisions.

A study shows that the accumulation of satellite debris could eventually create Saturn-like rings around Earth, composed entirely of space garbage.

Space debris also poses a risk to Earth's population, potentially causing injuries and destruction. In November 2023, the Federal Aviation Administration (FAA) warned that falling debris from SpaceX's Starlink satellites could injure or kill a person every two years and might even down an aircraft.

Falling space objects is already a reality. In March 2024, a part of a space cargo pallet hit Florida. NASA had expected the Earth’s atmosphere to burn the garbage, but it survived and hit a residential area, causing damage.

Apart from the danger of falling pieces of metal, there is also an invisible danger – burning satellites leave behind small metal particles, aluminum oxides, that accumulate in the upper atmosphere.