Astronauts currently face the challenge of washing laundry in space, but that scenario may soon change. This innovation could lead to enhanced comfort for individuals on extended missions to the Moon or Mars.

On the International Space Station (ISS), astronauts typically wear the same clothing for multiple days before returning them to Earth, where they incinerate upon re-entry. While this approach suffices for shorter missions, it becomes impractical for extended missions without frequent supplies from Earth.

Recently, researchers Gabe Schuh and Chelsea Cassilly at NASA’s Marshall Space Flight Center have introduced a novel “washing gun” that projects cold plasma onto fabrics, effectively eliminating odor-causing microorganisms. This breakthrough was highlighted at the recent Astrobiology Science Conference held in Wisconsin on May 21st.

The mechanism involves igniting a mixture of helium, air, and water vapor with a strong electric burst, resulting in oxygen ions that permeate the fabric, attacking and destroying harmful microorganisms through oxidative stress.

One significant advantage of this plasma method over others, such as ultraviolet light exposure, is its effectiveness against resistant microorganisms. “Certain microorganisms can withstand UV light, but based on our tests, there’s no known microorganism resilient to oxidative stress. If they absorb it, they perish,” Xu explained. Laboratory tests demonstrated that the purple plasma beam decreased spore colonies on cotton cloth samples from 250,000 to approximately 60,000 colonies per milliliter.

This cleaning technique operates without damaging the fabric or presenting safety hazards. “When we think about plasma jets, we often visualize extremely hot phenomena like lightning or welding. However, with a jet designed for this application, it becomes safe for home use,” Xu states.

Despite its current limitation to disinfect only small fabric patches at a time, effectively scaling it for household use remains a challenge. Xu and Cassilly are advancing two alternative versions: a “plasma washer” that channels plasma into a chamber containing the fabric and a dual plasma jet vacuum suitable for surface applications.

As Schuh remarked, “For long-term habitats on the Moon or Mars, astronauts will undoubtedly desire a clean and comfortable environment, but achieving that necessitates effective cleaning solutions. Plasma jets could make this vision a reality.”