Putting objects in space is expensive, and the heavier they are, the more it costs. Satellites for Earth Observation and Surveillance need large dishes to maximize the radio waves they can collect. A team at Nottingham Trent University are trying to resolve the resulting conundrum by knitting themselves an ultralight satellite.
“Few people associate knitting with high-end space technology,” said project lead Professor Tilak Dias in a statement. “However due to the advancements in knitting technology we can now knit an antenna which is extremely lightweight, cost-effective and robust enough to withstand solar radiation.”
As any knitter can tell you, having the right material matters. In the case of the dishes Dias is designing, that material is gold-plated wire less than 50 micrometers (0.002 inches) thick, thinner than most human hairs. The gold-plating offers protection against the radiation of space. Although gold is not light, as the most malleable of all the elements, the plating can be so thin it adds very little to the telescope's weight.
Knitting the wires into the shape of a parabolic disk makes for less waste than alternative techniques. As team member Dr Will Hurley noted: “When you consider that knitted gold wire can cost hundreds of thousands of pounds per square metre, waste is something we have to be very mindful of.” A knitted mesh also has the flexibility to be folded up tight during launch without damage.
Mike Lawton, CEO of Oxford Space Systems who are collaborating on the work, told IFLScience dishes of up to 25 meters (82 feet) are needed for spy agencies to detect the weak leakage of signals, while half that size is standard for Earth Observation.
This is not the only example of traditional textile crafts being pressed into the service of science.
The Hyperbolic Crochet Coral Reef lets volunteers crochet woolen models of corals. The project is popular in museums and art galleries and draws attention to the dangers facing coral reefs worldwide, but has also helped apply mathematical techniques to understanding the shapes of actual corals, and other marine lifeforms, such as kelp and sea slugs. The work draws on mathematicians' realization that crochet could be used to create models of hyperbolic space, and therefore help visualize it. Founded by science communicator Margaret Wertheim and her sister Christine, it is now possibly the largest art project in the world.
The Föhr Reef is part of the "Hyperbolic Crochet Coral Reef" project exhibited in Tübingen (Germany) in the Museum of the Universitäty Tübingen CC 3.0
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