The next generation of customised space suits may be moulded around astronauts’ genitalia to filter water from urine!

When you imagine an astronaut, you probably envision the iconic white spacesuit, the helmet, and the floating in zero gravity. What you probably don't think about is the less glamorous aspect of spacewalks: the need for astronauts to relieve themselves.

Since the 1970s, this has been managed with the Maximum Absorbency Garment (MAG), essentially a high-tech diaper. However, this solution is far from perfect, often leading to discomfort, leaks, and even health issues like urinary tract infections.

Inspiration from sci-fi

The newest urine-handling tech has drawn inspiration from the Dune franchise’s stillsuits. These fictional suits could purify and recycle bodily fluids into drinkable water. Now, what was once science fiction is inching closer to reality with a novel urine collection and filtration system designed for spacesuits.

The new design incorporates a vacuum-based external catheter leading to a sophisticated forward-reverse osmosis unit. This setup promises a continuous supply of potable water, ensuring astronaut well-being during long spacewalks.
With upcoming moon and Mars missions on the horizon — Artemis II and III in 2025 and 2026, and potential crewed missions to Mars by the early 2030s — this innovation couldn't come at a better time. Current NASA spacesuits only provide astronauts with one litre of water, which is inadequate for the extended duration of lunar spacewalks that can last up to ten hours, or even 24 hours in emergencies.

How does the new spacesuit work?

The new urine collection device is an undergarment made of multiple layers of flexible fabric, connected to a silicone collection cup designed to fit around the genitalia. The cup’s inner face draws urine away from the body and uses a vacuum pump to suck it into the system. An RFID tag linked to an absorbent hydrogel activates the pump upon detecting moisture.

“Though the garment must be tested on a wider variety of body types and individuals, comfort has improved significantly already based on internal fit testing feedback,” the authors note.

The collected urine is then diverted to a two-step, integrated forward and reverse osmosis filtration system, where it’s purified with 87% efficiency. The resulting water, enriched with electrolytes, is pumped into the in-suit drink bag, ready for consumption. The entire process of collecting and purifying 500ml of urine takes just five minutes.

This innovative system is housed in a compact, lightweight backpack, measuring 38 by 23 by 23 cm and weighing around eight kilograms. Powered by a 20.5V battery with a capacity of 40 amp-hours, it includes control pumps, sensors, and a liquid-crystal display screen, ensuring ease of use and monitoring.
With the prototype now available, the next step involves rigorous testing under simulated microgravity conditions to ensure functionality and safety before deployment in actual space missions. As we prepare for more ambitious space missions, such cutting-edge technologies will play a crucial role in ensuring the comfort, health, and efficiency of astronauts venturing into the final frontier.

The findings of this research have been published in Frontiers in Space Technologies and can be accessed here.