The mundane act of relieving oneself while clad in a spacesuit on a spacewalk might seem like a humorous footnote in the grand story of space exploration, but it has long been a considerable challenge for astronauts. NASA's suits have traditionally employed the Maximum Absorbency Garment (MAG), essentially a high-tech diaper, to manage waste. However, as future missions such as Artemis eye the Moon and Mars, there's a pressing need for better solutions both for comfort and practicality.
Inspired by the 'stillsuits' from Frank Herbert's famed sci-fi series 'Dune', Cornell University researchers have come up with a prototype that could change the game entirely. This innovative system recycles urine into potable water, addressing not only the issue of waste management but also the critical need for hydration during extended spacewalks. The concept, which has moved from the pages of science fiction to a real technological breakthrough, might ready itself for deployment in NASA's Artemis missions aiming for lunar exploration by 2026 and beyond to Mars in the early 2030s.
"Building a real-life stillsuit was always a bit of a dream," said Sofia Etlin, a research staff member at Weill Cornell Medicine and an enthusiast of the 'Dune' series. Etlin leads this pioneering project along with Professor Christopher Mason, also at Cornell. Their work, published in 'Frontiers in Space Technology', details a sophisticated urine collection and filtration system that could be a key upgrade for astronaut hygiene and mission effectiveness.
The current waste management system, the MAG, has been in use since the late 1970s. It's plagued by issues such as discomfort, leaks, and the occasional urinary tract infection. "The MAG has reportedly caused health issues such as gastrointestinal distress and even UTIs. And astronauts currently have only one liter of water available in their suit drink bags, which is simply not enough for the upcoming lunar missions, where spacewalks could last up to ten hours or even longer during emergencies," Etlin explained.
The new design by Etlin and her team includes an undergarment made from multiple layers of fabric, which is connected to a molded silicone collection cup. This cup comes in different shapes for men and women to fit snugly around the genitalia. It's equipped with a polyester microfiber lining that wicks urine away from the skin to an internal surface from where a vacuum pump sucks it up. A RFID tag, linked to an absorbent hydrogel, causes the pump to activate as soon as moisture is detected.
Once collected, the urine goes through a two-step filtration process. Using forward and reverse osmosis, the system recovers water from the urine with an efficiency of 87% and a purification time of about 500 ml in five minutes. The cleaned water is subsequently enriched with electrolytes and returned to an in-suit drinking bag. This mechanism ensures astronauts are well-hydrated by constantly providing them with safe drinking water.
The filtration unit, which includes control pumps, sensors, and a display screen, is powered by a 20.5V battery with a capacity of 40 amp-hours. The entire assembly weighs about eight kilograms and takes up minimal space, designed to be worn on the back of a spacesuit.
"It's a fascinating blend of complex technology and incremental innovations," Professor Mason commented. The research team plans to test this device in simulated microgravity conditions to verify its functionality and ensure its safety for use in actual space missions.
Onboard the International Space Station (ISS), the recycling of wastewater, including urine, has already proven effective, providing an important precedent for this new system. However, the existing ISS system is bulky and not suited for the demands of a spacesuit. The novel system addresses this, providing a more compact and efficient alternative.
The idea of recycling urine might initially seem unappealing, but for astronauts on long-duration missions, the ability to turn waste into a valuable resource is crucial. As one astronaut humorously noted, "If you're giving NASA billions of dollars, you wouldn't expect to still be using diapers!” Future spacesuit designs will have to evolve to support the extended, and perhaps more commercial, activities planned beyond Earth's orbit.
Envisioning a future where advanced wearables are standard, researchers are already considering terrestrial applications for this technology. Potential applications include long hiking trips, firefighting missions, or any scenario where water might be scarce. The integration of such a system into daily wear could revolutionize personal hydration strategies, possibly extending its benefits beyond the realm of space.
One poignant takeaway from this endeavor is the intersection of science fiction dreams with scientific reality. Technologies inspired by visionary works like 'Dune' not only fuel our imagination but also drive tangible advancements that solve real-world problems. Dr. Mason's concluding thoughts capture this sentiment splendidly: "Even in the absence of a vast desert planet like Arrakis, this could significantly improve astronauts' spacewalking experiences."
As preparations for the next great leap in human space exploration ramp up, innovations like these remind us of the symbiotic relationship between imagination and invention. Whether for an astronaut venturing onto the lunar surface or a hiker in a remote wilderness, the promise of transforming waste into life-support underscores an enduring truth: necessity is indeed the mother of invention.
