Astronauts heading on long missions to Mars could face a surprisingly ordinary problem: how to keep their clothes clean without wasting precious water.
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Astronauts → head → water
Scientists at the University of Alabama in Huntsville, working with
NASA's Marshall Space Flight Center, have developed a small device that could offer a solution.
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that → work → solution
Nicknamed a “laundry gun”, the prototype shoots cold plasma at fabric to reduce the number of microbes living on astronauts' clothes and other soft surfaces.
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prototype → nickname → clothes
In early tests, the device reduced microbial spore colonies on fabric by more than 75%.
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device → reduce → %
Unlike a washing machine, it does not use large amounts of water or cleaning chemicals.
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it → use → water
The researchers say the technology could eventually help astronauts stay healthier during long missions where every kilogram of supplies and every drop of water matters.
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kilogram → say → water
How the ‘laundry gun’ works
The device uses cold plasma, an electrically charged mixture of particles that can be produced without heating the fabric to extremely high temperatures.
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that → work → temperatures
When the plasma reaches the material, energetic particles interact with gases such as oxygen and water vapour in the surrounding air.
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particles → reach → air
These reactions create highly reactive molecules that can attack and damage the outer membranes of microorganisms.
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that → create → microorganisms
The process is designed to reduce bacteria and other microbes living on fabric rather than physically wash away dirt.
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process → design → dirt
The current prototype is about the size of a pen and treats only a small patch of material at a time.
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prototype → treat → time
Early laboratory tests produced promising results.
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tests → produce → results
Researchers found that plasma treatment reduced spore colonies on a fabric sample by more than 75%.
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treatment → find → %
The result suggests the technology could substantially lower the microbial load on clothing and other soft surfaces.
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technology → suggest → clothing
That could be important inside a spacecraft because astronauts live together in a confined environment for long periods, giving microorganisms plenty of opportunities to spread.
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astronauts → live → opportunities
However, the result does not mean the device kills 75% of every microorganism on every type of fabric.
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device → mean → fabric
More testing is needed to determine how well the technology works against different microbes and under realistic spaceflight conditions.
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technology → need → conditions
The plasma can help kill or reduce microbes, but it does not remove visible dirt, food stains or other substances from clothing.
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it → help → clothing
The researchers have even noted that the device will not remove stains such as coffee marks.
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device → note → marks
Astronauts could potentially reuse clothing for longer if microbial contamination can be controlled without repeatedly washing the fabric in water.
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contamination → reuse → water
Why Mars missions need a new approach
Laundry is much harder in space than it is on Earth because water is a limited and valuable resource.
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water → need → Earth
Astronauts on the International Space Station do not have a conventional washing machine.
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Astronauts → have → machine
Instead, clothing is worn multiple times and eventually discarded or replaced with supplies delivered from Earth.
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clothing → wear → Earth
That approach is possible because the ISS regularly receives cargo.
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ISS → receive → cargo
A crew travelling to Mars would face a very different situation.
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crew → travel → situation
The journey would last months and there would be no practical way to regularly send replacement clothes from Earth.
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journey → last → Earth
Reducing the amount of clothing, water and cleaning supplies required could therefore make a major difference.
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Reducing → reduce → difference
The device could also sanitise spacesuits and tools
The researchers are looking beyond everyday clothing.
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researchers → sanitise → clothing
The same plasma technology could potentially be used to sanitise spacesuits, tools and other equipment before astronauts leave a habitat and operate on another world.
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astronauts → use → world
This could have implications for planetary protection, where space agencies try to prevent Earth-based microorganisms from being transported to other worlds.
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agencies → have → worlds
The technology could also potentially be used on bedding and other soft surfaces inside a spacecraft or habitat.
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technology → use → spacecraft
These applications remain under development, but they show why the researchers see the device as more than a simple alternative to laundry.
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researchers → remain → laundry
The plasma comes with an ozone problem
The technology also creates a challenge that researchers must solve before it can be safely used inside a spacecraft.
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it → come → spacecraft
Plasma interactions with oxygen can produce ozone, which can be harmful at high concentrations.
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which → produce → concentrations
That is particularly important in a spacecraft where the same air is continuously circulated and reused.
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air → circulate → spacecraft
The researchers are therefore working on a filtration system that could remove excess ozone generated during treatment.
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that → work → treatment
A future space-ready version would need to balance effective microbial reduction with safe air quality, low power consumption and minimal impact on the fabric being treated.
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version → need → fabric
Researchers want a larger version
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Researchers → want → version
The current pen-sized prototype is too small to clean or sanitise an entire item of clothing efficiently.
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prototype → clean → clothing
It can treat only about a square centimetre at a time, meaning an astronaut could not realistically use it on a complete shirt or spacesuit in its present form.
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astronaut → treat → form
…and 12 more, not listed.
The Aporia
