ESA wants to make astronauts' shared spacesuit underwear more hygienic

Yes, it's true — astronauts share 'underwear' when they put on spacesuits to work outside of the International Space Station. This isn't quite the same type of underwear you're thinking of, as the astronauts first put on a disposable diaper, then the full-body underwear layer. Still, there are some downsides to this arrangement that the ESA is attempting to address with a new project.

The International Space Station — and future space stations that will eventually replace it — are home to a number of spacesuits used during spacewalks. These suits are highly complex and composed of multiple layers designed to protect the person wearing them, including maintaining their comfort. Rather than assigning each astronaut their own suit, the teams share suits.

The spacesuit ensemble involves putting on a disposable diaper, then a Liquid Cooling and Ventilation Garment described as similar to long underwear. This garment, the LCVG, contains gas ventilation and liquid cooling tubes for comfort while wearing the suit. The LCVG likewise sits against the wearer's skin and, of key importance, is shared by other astronauts who use the suit.

With attention to planned long-term space missions, once the Gateway is deployed, the European Space Agency has announced a new project called Biocidal Advanced Coating Technology for Reducing Microbial Activity (BACTeRMA). The effort will involve seeking new antimicrobial textiles that can be used for spacesuit underwear layers to address hygiene concerns.

For now, space agencies utilize copper and silver as antimicrobial materials, but the metals can tarnish over time and cause skin irritation. To address this, the ESA has teamed with Vienna Textile Lab due to its 'unique bacteriographic collection,' namely microorganisms whose metabolites may offer protective properties as a textile finish.

The project will last two years and include testing various antimicrobial textile finishes in a variety of scenarios, including exposure to radiation, simulated lunar dust, and more.