Space-age materials

Hardy, non-perennial

Making satellites out of wood

THE SPACE age was built on clever materials. The business ends of rocket engines are composed of Inconel, a family of heat-and-corrosion-resistant nickel-chromium alloys developed in the 1940s. The “gold foil” adorning many satellites is, in fact, a form of insulation made from layers of Kapton and metallised Mylar, a pair of artificial polymers from the 1950s and 1960s. SpaceX’s Dragon spacecraft use a heat shield made of phenolic-impregnated carbon to protect astronauts during atmospheric re-entry.

But it is not just humans in lab coats who can come up with whizzy substances. Sumitomo Forestry, a Japanese firm, and Kyoto University are pondering the idea of building satellites out of an advanced, high-performance composite made from cellulose and lignin, a pair of complex polymers which are strong in tension and compression respectively. This material is both cheap and abundant. It is self-assembling and requires only simple chemical inputs. Manufacture can be entirely automated, requiring no human oversight. Translated from chemist-speak, they want to make satellites out of wood.

The research team argue that wood offers two advantages. Unlike metal, seasoned timber is easily penetrated by radio waves. That means communication antennas, sensors and the like…