Evrim Yazgin
Cosmos science journalist
Astronauts on spacewalks have to urinate into their suits.
Unlike the wastewater on board the International Space Station, the water in the urine produced on spacewalks is not recycled. It’s also uncomfortable and unhygienic.
A solution to this problem would be a full-body ‘stillsuit’ such as those described in Frank Herbert’s book Dune, recently reimagined in a series of blockbuster films. In Dune, the stillsuit wearer conserves body moisture which might otherwise be lost in the form of sweat and urine – a must in the deserts of Paul Atreides’s new home of Arrakis.
But that’s science fiction, right?
It may be a science reality in the not-too-distant future. Researchers have designed a prototype urine collection and filtration system for spacesuits. Their study is published in the open-access journal Frontiers in Space Technology.
“The design includes a vacuum-based external catheter leading to a combined forward-reverse osmosis unit, providing a continuous supply of potable water with multiple safety mechanisms to ensure astronaut wellbeing,” explains first author Sofia Etlin, a research staff member at Weill Cornell Medicine and Cornell University in New York.
Such innovations in wearable technology may be vital as humans again embark upon an exploration of space.
For the first time since the 1970s, the Artemis missions are looking to send people to the Moon. Lift off could be as early as 2025. This is expected to be followed by crewed missions to Mars in the early 2030s.
Currently, astronauts relieve themselves into “maximum absorbency garments” (MAGs) which have been in use since the 1970s. They are something like adult diapers.
Astronauts have long complained of the lack of comfort and hygiene of the MAG.
“The MAG has reportedly leaked and caused health issues such as urinary tract infections and gastrointestinal distress,” Etlin says. “Additionally, astronauts currently have only 1 litre of water available in their in-suit drink bags. This is insufficient for longer-lasting lunar spacewalks, which can last 10 hours, and even up to 24 hours in an emergency.”
Etlin’s new urine collection device includes an undergarment made of multiple layers of flexible fabric. A collection cup of moulded silicon fits around the genitals to collect urine.
Polyester microfibre draws the moisture away from the body to a vacuum pump and diverts itit to the filtration system where it is recycled with an efficiency of 87%.
The system is 38cm by 23cm by 23cm and weighs 8kg.
“Our system can be tested in simulated microgravity conditions, as microgravity is the primary space factor we must account for. These tests will ensure the system’s functionality and safety before it is deployed in actual space missions,” says lead author Christopher E Mason, a professor at Cornell.
