A first-of-a-kind spacecraft is set to make history later this year, and will do so using materials you could find at your local hardware store. The world's first wooden satellite will enter orbit as a box made largely of birch plywood, which will be packed with sensors from the European Space Agency (ESA) to study the potential of the material in space.
The Woodsat is a CubeSat measuring around 10 cm (4 in) along each side, but what's unique about this box-shaped miniature satellite is that the surface panels will be made from plywood. In fact, the only non-wooden parts featured on the outside are the corner aluminum railings that will help with its deployment once in space, along with a metal selfie stick.
The Woodsat is the brainchild of Finnish science journalist Jari Makinen, who also heads up a company called Arctic Astronauts that sells replica CubeSats for educational use and space hobbyists.
“I’ve always enjoyed making model planes, involving a lot of wooden parts," says Makinen. "Having worked in the space education field, this got me wondering; why don’t we fly any wooden materials in space? So I had the idea first of all to fly a wooden satellite up to the stratosphere, aboard a weather balloon. That happened in 2017, with a wooden version of KitSat. That having gone well, we decided to upgrade it and actually go into orbit."
Makinen has since secured commercial backing for a mission to space, and lined up a launch partner in Rocket Lab, which will supply its Electron booster for lift-off. ESA, meanwhile is working on a sensor suite that, along with the onboard cameras, will track the satellite's performance in space.
One camera will be mounted to the selfie stick to capture images of the wooden surfaces, while also onboard will be an LED light, a sensor to monitor the pressure levels in the Woodsat's cavities and a contamination sensor called a quartz crystal microbalance. This will track tiny deposits that take shape on the satellite coming from either the onboard electronics or the surface of the wood, which itself had to be treated in preparation for the mission.
“The main difference is that ordinary plywood is too humid for space uses, so we place our wood in a thermal vacuum chamber to dry it out," explains Woodsat's chief engineer Samuli Nyman. "Then we also perform atomic layer deposition, adding a very thin aluminum oxide layer – typically used to encapsulate electronics. This should minimize any unwanted vapors from the wood, known as ‘outgassing’ in the space field, while also protecting against the erosive effects of atomic oxygen. We’ll also be testing other varnishes and lacquers on some sections of the wood.”
The mission planners expect the Woodsat to survive this atomic oxygen, which forms near the fringes of the atmosphere when oxygen molecules are broken down by the Sun's ultraviolet radiation. They do, however, expect the wood to be darkened by this ultraviolet radiation as it orbits the planet at an altitude of around 500 to 600 km (310 to 372 miles). All going to plan, Woodsat will launch before the end of the year.
“In the end, Woodsat is simply a beautiful object in terms of traditional Nordic design and simplicity, it should be very interesting to see it in orbit,” says Makinen. “Our hope is it helps inspire people to take increased interest in satellites and the space sector as something that already touches all our lives, and is only going to get bigger in future.”
Source: ESA