Space

Dealing with spaceflight's dirty secret

Dealing with spaceflight's dirty secret
In space, no one can hear you scream, but there's another downside – currently, no one can do laundry either
In space, no one can hear you scream, but there's another downside – currently, no one can do laundry either
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In space, no one can hear you scream, but there's another downside – currently, no one can do laundry either
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In space, no one can hear you scream, but there's another downside – currently, no one can do laundry either
Christina Morrison presented her research at the 2017 Arizona Space Grant Symposium in Tempe
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Christina Morrison presented her research at the 2017 Arizona Space Grant Symposium in Tempe

One of the dirty secrets of spaceflight is that, in space, there's no such thing as laundry day. That's because no one has figured out an economical way to wash clothes in orbit. To make things a bit less manky, a University of Arizona undergraduate is developing a new system that may one day allow astronauts to clean their clothes and make them last longer while conserving water.

Scientists and engineers have achieved wonders in space, but keeping clean isn't one of them. In the days of the Space Race, astronauts had to put up with living in a tin can for days or weeks on end without a change of clothes or a proper wash beyond moist towelettes. Improvements came with Skylab and the Space Shuttle, but on the International Space Station {ISS}, things are still about as basic as washing up in a railway station lavatory.

This is due partly to the way water acts in space. Instead of falling or flowing, it floats about in globules until it adheres to something by surface tension. But the main reason is cost. At US$10,000 per pound to get to the station, using water for washing makes less budgetary sense than brushing your teeth with Salon Blanc de Blancs Le Mesnil-sur-Oger 2002 at $899 a bottle.

Instead, crews on the International Space Station use ways of economizing on water that are usually adopted by single-hand round-the-world sailors. "Showering" is basically taking a sponge bath using premixed bags of soap and warm water, while washing hair means applications of a special no-rinse shampoo.

As to laundry, there isn't one. It's cheaper for astronauts to bring along enough changes of clothes to get them through the mission, though "enough" often isn't. The crews wear items for months at a time, and throw them away before they get too ripe – or develop language skills. Not surprisingly, the dirty clothes end up being incinerated in the Earth's atmosphere along with the rest of the garbage.

Christina Morrison presented her research at the 2017 Arizona Space Grant Symposium in Tempe
Christina Morrison presented her research at the 2017 Arizona Space Grant Symposium in Tempe

In search of an alternative, Arizona undergraduate research assistant Christina Morrison, with the help of UA professor of microbiology Charles Gerba, is working under a NASA Space Grant to look at an alternative laundry technique that saves water and cuts down on throwing away clothes.

Morrison's idea is to get the clothes cleaner and a lot less smelly by using a combination of silver and hydrogen peroxide. Both have strong antibiotic properties on their own, and together they have a much stronger effect when combined in water. But what Morrison is proposing isn't just scrubbing space fatigues with silver and peroxide, which would have its own logistical problems. What she wants to do is incorporate silver-ion threads into astronaut clothing, similar to those in germ-killing socks.

To test this idea, Morrison and Gerba took swatches of cloth from antimicrobial socks and treated them with low concentrations of hydrogen peroxide. They then exposed them to Staphylococcus aureus, a common bacterium frequently found on human skin, (as well as in the nose and respiratory tract).

They found the treated swatches exhibited a 99.999 percent reduction in bacteria, while the untreated had only a 43.76 percent reduction. Granted, it isn't the same as a good run through a washing machine with detergent and bleach, but it is better than today's nothing.

"The clothes will stay germ-free longer, because of the silver ions, and can be laundered by adding hydrogen peroxide," says Morrison. "Washed just twice, one shirt could stay microbe- and odor-free in the same length of time an astronaut would normally wear and discard three shirts. This saved mass would drastically reduce the amount of clothing needed to launch into space and allow longer missions."

Morrison says that the next step will be to have volunteers wear antimicrobial socks or regular socks and then treat them with peroxide. They will then be tested by a second group, who will smell them – no bets on which group will be the most desirable.

Source: University of Arizona

7 comments
7 comments
Brian Smith
Neat idea, alternatively (or additionally): Contain the dirty clothing in a folded / stacked flat mesh frame that is attached to a special airlock. Once the garments are exposed to the vacuum of space the mesh frames could unfold like a set if solor panels. Sterilization should be accomplished thanks to the hard vacuum, solor radiation and the hot and cold extremes.
I suppose the trick would be to design an airlock system that loses as little atmosphere as possible. Between designing it to be as small/thin as possible to still do the job. Maybe even design the inside with a membrane that can be pushed in to the airlock's internal space to compress the clothing and reduce the airlock's internal volume further while pumping as much of the air in the airlock in to the space station as possible.
PhilipKFreeman
I think the ISS is like other nasa pipe dreams.
Martin L Hedington
"Manky"? Ex Navy by any chance David?
cwolf88
Copper-treated clothing is already available. Better than silver. Also treats things like yeast infections, skin infections, etc.
Ultrasonic washing machines are also available. Used laundry water can be processed just like astronaut's urine.
Paul Anthony
They could use Nicola Tesla's Cold Fire to obtain a superior waterless wash. https://www.exposingtruth.com/teslas-cold-fire-explained/
Douglas Bennett Rogers
The problem must be launching the extra mass of water. Water recycling is already in place. Also, didn't see pyrolytic cleaning mentioned.
Fretting Freddy the Ferret pressing the Fret
They could use an UV lamp to further sterilize clothing similar to how people hang wet clothing outside in the Sun.