Monday, December 4, 2023

World’s first wooden satellite to launch this year

The world’s first wooden satellite is on the way, in the shape of the Finnish WISA Woodsat. It will be launched into orbit at the end of 2021 as part of an environmentally friendly space exploration test project. The satellite will be packed with sensors from the European Space Agency (ESA) to study the material’s potential in space. It aims to access whether in the future it is possible to build a space station or spacecraft out of wood.

The Woodsat is a CubeSat measuring 10cm along each side and weighing 1kg, with surface panels made from plywood. Woodsat’s only non-wooden external parts are corner aluminum rails used for its deployment into space plus a metal selfie stick.

The mission was initiated by Jari Makinen, Finnish writer, and broadcaster, who also heads up a company called Arctic Astronauts that sells replica CubeSats for educational use and space hobbyists.

The satellite will be outfitted with two cameras, one of which will be mounted to the selfie stick, allowing the mission team to observe how the satellite’s plywood surface changes in the space environment. The LED light and sensors will monitor the pressure levels in the Woodsat’s cavities especially in the spacecraft’s first days in orbit.

The other item is a quartz crystal microbalance, serving as a highly sensitive contamination monitoring tool, measuring any faint deposits in the nanogram range coming from onboard electronics as well as the wooden surfaces themselves.

The base material for plywood is birch, and we’re using basically just the same as you’d find in a hardware store or to make furniture,” explains Woodsat chief engineer and Arctic Astronatics co-founder Samuli Nyman.

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. 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 satellite will undergo tests exposed to extreme temperatures, vacuum pressure, and space radiation. It will be put into orbit with the help of the Electron carrier rocket from the Rocket Lab company. The launch will take place from a space base located on the Mahia peninsula in New Zealand.

Pre-flight testing suggests the satellite, which will orbit at around 500-600 km altitude in a roughly polar Sun-synchronous orbit, should survive its atomic oxygen exposure. But the wood is expected to be darkened by the ultraviolet radiation of unfiltered sunlight.

The satellite, which is powered by nine small solar cells, will be equipped with an amateur radio payload, allowing amateurs to relay radio signals and images around the globe.

“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,” continues Jari. “Our hope is it helps inspire people to take an 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.”