Japanese researchers have managed to create one of the most original spacecraft in the world – a small wooden satellite, The Guardian reports.
The satellite was made by scientists from Kyoto University. Photo: Archive
The LignoSat probe was made of magnolia wood, which during tests on the International Space Station (ISS) proved to be extremely crack-resistant and stable. Plans are being finalized to launch the probe on a US rocket this summer.
This wooden satellite was created by scientists at Kyoto University and Sumitomo Forestry to test the possibility of using biodegradable materials such as wood to see if they can be an environmentally friendly alternative to the metals they are made of currently build all satellites.
“It blew us away”
“All satellites that re-enter the Earth's atmosphere burn up and create small alumina particles, which will float in the upper atmosphere for many years.”, recently attracted the attention of Takao Doi, a Japanese astronaut and aerospace engineer at Kyoto University. “Ultimately, it will affect the Earth's environment.”
Trying to find a solution to this matter, scientists in Kyoto developed a project to evaluate types of wood to find out how well they can withstand the conditions of space launch and long flights in orbit around the Earth. The first tests were carried out in laboratories that recreated the conditions in space, and the wooden samples did not undergo noticeable changes in mass or signs of decay or damage.
“We were amazed that wood is able to withstand these conditions“, said Koji Murata, the project leader.
After the tests were completed, the samples were sent to the ISS, where they underwent exposure tests for almost a year before being brought back to Earth. Again, these showed little sign of decay, a phenomenon Murata attributed to the fact that there is no oxygen in space to cause the wood to burn, and no living things to cause it to rot.
“It is durable and stable”
Other types of wood were tested, including Japanese cherry, and magnolia wood was found to be the most durable. It has currently been used to make the Kyoto wooden satellite, which will undergo a series of experiments that will determine how well the spacecraft performs in orbit, Murata said.
“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 can be prone to dimensional changes and cracks in the other direction”he told the Observer.
Murata said no final decision has yet been made on the launch vehicle, with options now narrowed down to a flight this summer with an Orbital Sciences Cygnus supply ship to the ISS or a similar SpaceX Dragon mission later in the year. The probe – which is about the size of a coffee cup – is expected to remain in space for a minimum of six months before it is allowed to enter the upper atmosphere.
If LignoSat proves effective during its operation in orbit, then it may be possible to use wood as a base material for the manufacture of other satellites. More than 2,000 spacecraft are estimated to be launched annually in the coming years, and the aluminum they will leave in the upper atmosphere as they burn up on re-entry could soon raise major environmental concerns.
Recent studies by scientists at the University of British Columbia, Canada, indicated that aluminum from satellites re-entering the atmosphere could cause serious depletion of the ozone layer, which protects the Earth from the Sun's ultraviolet radiation, and could affect , at the same time, the amount of sunlight that crosses the atmosphere and reaches the ground.
However, this shouldn't be a problem with wooden satellites like LignoSat, which, when it burns up on re-entry after completing its mission, will only produce a fine stream of biodegradable ash.
