Hamiltonian Hugh McCarroll named semi-finalist in Nasa Space Poop Challenge
It's the dark side of the moon walk.
The zero-gravity environment of space makes doing a poo complicated, and Nasa was seeking a portable-bathroom solution.
Hugh McCarroll, retired aeronautical engineer and former head of Hamilton Airport, answered the call.
Last week, he was named a semi-finalist in the Nasa Space Poop Challenge.
"This aspect of human space travel is not glamorous … you can't keep a [nappy] on and remain hygienic and safe for more than about 10 or 12 hours," he says.
Spacesuits are essential for the survival of astronauts, but they're not built for emergency defecation situations.
Adult nappies, the current spacesuit toilet, are suitable in the Earth's lower-orbit where terra firma is only hours away in the event of a disaster.
Shooting for the stars - or at least the moon's orbit - will take humans farther away from Earth. This means a spacesuit might be worn for days, not hours.
Nappy rash is only a minor concern, the risk of infection is real.
So Nasa has asked the world's inventors for a solution through HeroX, a website that hopes to crowdsource technological breakthroughs through competitions for inventors.
A total prize pool of $30,000 was on offer for an in-suit, hands-free waste management system which could hold six days worth of poo, pee and menstrual blood.
McCarroll doesn't remember how he came across the space poo challenge, but it immediately gripped him.
"Anything nerdy I'm into," he says.
At nine-years-old, he gave a presentation on multi-stage rockets to his primary school class in Wellington's Hutt Valley.
At 14, he was captivated by Sputnik's launch into orbit.
At 17, he was devastated to discover poor eyesight meant he couldn't fly for the air force, so he became an aeronautical engineer.
And at 74, he looked to design a space poo solution.
But a busy Christmas was approaching, and McCarroll worried his wife Rose would not allow him the distraction.
So he didn't tell her. or his three daughters.
"It would have been a huge joke," he says.
He fired up a decade-old laptop and got to work on free 3D modelling software.
"Each night I'd be working on it … and I got more and more enthusiastic about it."
Reference material wasn't required and he didn't need to do any research and development.
A plastic bag was the most simple solution. It is basic engineering design, he says, he just drew on years of experience.
The end product is a pair of merino long-johns with a zipper opening for when nature calls.
When nature calls, the astronaut simply presses a button on the exterior of the spacesuit.
The two halves of the zipper, which runs from the crotch to the buttocks, move apart and press against the inner thighs and the buttocks, creating a sealed opening.
The astronaut then does the business. The bodily fluids enter over trousers, which act as a large plastic bag.
The trousers can contain 25 litres, McCarroll estimates.
"All that volume is available for the whoopies to float around. I envision they would slide and form a mush."
The movement of the astronauts legs, McCarroll expects, would great a micro-gravity which would push it away from the body.
Rings of nappy-like material within the lower-legs would absorb the "slush".
A little nozzle in the zipper sprays baby oil as it closes the portal, which "pushes away any other solids or liquids, bearing in mind the wees and poos are floating".
Over 5000 entries were submitted. McCarroll was excited to be named a finalist at the beginning of February, so he told Rose about the challenge.
Sadly, he won't be testing the design himself.
On February 16, he was named a semi-finalist with 20 other individuals and teams.
"I was thrilled beyond measure," he says.
The three winners were an American flight surgeon, a team of three-engineers from Houston and a British physicist who previously designed magic tricks.
The flight surgeon's first-place design, a small airlock in a suit's crotch, won him $15,000.
HeroX claims the Nasa Space Poop Challenge was record breaking not only for the site, but for innovation competitions in general.
"Space Poop is the new standard for how to get sh.. done," the website says.