A £150,000 prize for a device that can produce clean water from icy lunar soil has been won by a pair of inventors whose solution involves a microwave oven, a motorised device for feeding woodchips into a barbecue and sound waves.
The £1.2m Aqualunar Challenge, funded by the UK Space Agency’s international bilateral fund and split between Canadian-led and UK-led teams, is designed to encourage innovative solutions to the problem of producing drinking water from ice-rich regolith – rocks and dust – around the moon’s south pole.
“Nasa has set the goal of establishing a permanent crewed base on the moon by the end of the decade,” said Meganne Christian, a reserve astronaut and commercial exploration lead at the UK Space Agency who is also the chair of the Aqualunar Challenge judging panel. “Astronauts will need a reliable supply of water for drinking and growing food, as well as oxygen for air and hydrogen for fuel.”
However, extracting water is tricky. Temperatures on the moon can fall as low as -173C, there is low gravity and the pressure is so low that the moon can be considered as being under vacuum conditions.
Now a small Gloucestershire-based company called Naicker Scientific has come up with a solution that has won the UK arm of the challenge.
Lolan Naicker, the technical director of the company, said the victory was a surprise. “We were up against professors, larger teams, teams with access to the full might of UK university resources.”
Two runners up will also receive prizes: the father and sons team RedSpace Ltd will receive £100,000 for their Filtered Regolith Aqua Neutralisation Kit (Frank) while a team from Queen Mary University of London will receive £50,000 for AquaLunarPure – an approach based on the production of supercritical water.
Naicker said he and his colleague, Dr Ciarán Callaghan, shunned the brief of starting with contaminated ice and instead worked on the basis that this would first have to be extracted from the lunar regolith.
The result, called the SonoChem system, is a multi-step contraption worthy of Wallace and Gromit. Icy soil is fed into a hopper-like container from which it is continuously moved, by means of an auger, into a quartz tube that passes through the middle of a microwave oven that has been turned on its side. There it is heated, causing the water and various contaminants to vaporise, leaving the soil behind.
“After the microwave process these gases sublimate – they can’t liquefy because the pressure on the moon is so low,” said Naiker.
The gases are then frozen, before being liquified under pressure and subjected to ultrasound which creates millions of micro-bubbles in the contaminated water.
“When bubbles pop, there is actually a mini explosion that’s taking place,” he said, adding the localised high temperatures and pressures created cause contaminants in the water to either evaporate, or be broken down into other substances that subsequently evaporate, leaving behind clean water.
Naicker said that, in the absence of icy soil from the moon, the team tested the setup using homemade regolith based on building sand – although he has not tasted the water produced by the process.
Naiker said he has also been working on how to use the water to produce propellant for rocket engines. He hopes to use the prize money to grow his three-year-old business and is advertising for two graduates to help commercialise the technologies the team has developed.
“I’ve managed to enter into collaborations with two companies who are interested in a derivative of the lunar technology: in one case, a small, compact, portable water device, and in another case, an effluent treatment device,” he said, adding the team found ultrasound can be used to remove a host of contaminants from water including pharmaceutical products and pesticides.
