Future astronauts heading to the Moon or Mars may have a new way to keep harmful bacteria under control. Researchers have demonstrated that a small plasma device can sanitize contaminated fabric without water.
Long-duration space missions present challenges that extend well beyond transportation and life-support systems. Crews living for months in confined environments must also manage hygiene, contamination, and the buildup of microorganisms on everyday items. These concerns become more pressing as space agencies prepare for missions farther from Earth, where supplies cannot be replenished easily.
Today, astronauts aboard theInternational Space Station (ISS) do not wash their clothes. Instead, garments are worn repeatedly and discarded once they become too dirty. That system works because cargo spacecraft regularly deliver replacement supplies. Missions to the Moon and Mars, by contrast, will require more sustainable approaches for maintaining both cleanliness and crew health.
What Spacecraft Bacteria Reveal
Despite strict sanitation procedures, microbes remain aconstant presence inside the ISS. Swabs taken from areas including handrails and air vents have revealed substantial microbial populations on surfaces that often appear clean to the eye.
Live Science reported that some bacteria found aboard the station have adapted to thrive on metal surfaces. Scientists have also observed that bacteria can behave differently in microgravity, creating concerns about potential impacts on astronauts and spacecraft infrastructure.
The issue is not limited to clothing. Future habitats are expected to contain more fabric-based materials than the ISS currently does. Couches, bedding, and other furnishings designed to improve comfort during extended missions could also provide places where microorganisms accumulate over time.
“You have a couch that six astronauts, or however many, are sitting on day in, day out. How do you keep that thing sanitized so that they don’t spread germs to each other?” Gabe Xu, a professor at the University of Alabama, told Live Science.
Plasma Tested Against Bacteria Found on the ISS
To examine whether plasma could offer a practical sanitation tool, Xu worked with Chelsi Cassilly, a planetary protection engineer at NASA. Their experiment focused on Staphylococcus caprae, a bacterium commonly found on human skin that has also been detected aboard the ISS. The team cut an ordinary cotton T-shirt into small pieces and seeded the fabric with the bacteria. They then treated the samples using a compact device that generated a thin, bright-purple jet of plasma.
Often described as an energized gas, plasma contains charged particles capable of triggering chemical reactions. In this case, the plasma acted directly on the contaminated fabric. The researchers found that the treatment removed bacteria more effectively than sanitation methods currently used aboard the ISS, including dry vacuuming and chemical surface wipes. The objective was not to clean visible stains but to reduce microbial contamination.
“It is not going to remove the coffee stains from anyone’s T-shirt,” Xu said in comments reported by the source material. “But it will remove the stuff that will make you sick.”
A Water-Free Way to Sanitize Fabrics
The study showed that the plasma generatedreactive oxygen and nitrogen species when applied to the fabric. These compounds penetrated the fibers and disrupted bacterial cell membranes through oxidative stress. The researchers conducted tests lasting from 30 seconds to five minutes. During those experiments, they observed no noticeable damage to the cotton fibers being treated.
“We think that it’s probably not any worse than just normal wear and tear,” Xu told Live Science.
One of the technique’s main advantages is that it does not require water. Instead, the system operates using electricity and a working gas, eliminating the need for water-intensive cleaning equipment. That characteristic could make it particularly attractive for environments where resources must be carefully conserved.
The team is now extending its work to other microbial species known to inhabit human environments and spacecraft. Xu said the focus is on bacteria already known to exist in space habitats or routinely produced by human activity.
“We’re focusing on things that we know exist up there, or that we know that people produce just as a matter of fact throughout their day, since these are the things that would likely be in a space habitat.”
The preliminary findings were presented at The Astrobiology Science Conference in Madison. Researchers ultimately hope to adapt the technology into a handheld sanitation device that astronauts could use as part of routine housekeeping aboard spacecraft and future planetary habitats.
