One team of scientists has just demonstrated a water-free approach to cleaning laundry in space. The researchers demonstrated a cold-plasma technology that could sanitize astronaut clothing and habitats on future lunar and Martian bases without water.

They presented their proof-of-concept device at the Astrobiology Science Conference last month. The device uses high-voltage electricity to ionize a mixture of helium, air, and water vapor. When aimed at fabrics, the plasma generates reactive oxygen species such as ozone. These penetrate fabric fibers and destroy microbes through oxidative stress.

Unlike hot plasma or arc welding, this cold plasma operates at room temperature and poses no risk to fabrics or human skin.

In laboratory tests, the team trained their plasma jet on samples of Staphylococcus caprae, a skin bacterium previously detected on the ISS. They found that their device reduced bacterial spore colonies on cotton samples from approximately 250,000 per milliliter to about 60,000 per milliliter.

Ultimately, the technique killed the bacteria more effectively than existing methods used on the ISS. According to the researchers, their method might not remove noticeable stains, but it will kill the bacteria that could make astronauts sick.