The only place on the space station Astronauts aren’t supposed to clean up

While most of us are now more careful about keeping our homes and workplaces clean, aboard the International Space Station, cleanliness is imperative. Antibacterial measures are of great importance, as bacteria tend to accumulate in the constantly recirculated air inside the ISS. Every Saturday in space is a “cleanup day” where surfaces are wiped down and astronauts vacuum and collect trash.

But there is a place on board the station where cleaning is a no-no. But don’t worry, it’s all for science!

The MatISS experiment, or Microbial Aerosol Tethering on Innovative Surfaces in the International Space Station, tests five advanced materials and shows how well they can prevent pathogenic microorganisms from settling and developing in microgravity. MatISS also provided information on how biofilms attach to surfaces under microgravity conditions.

The experiment is sponsored by the French space agency CNES and was designed in 2016. Three iterations of the experiment were used on the ISS.

The first was MatISS-1, and four sample holders were installed over six months at three different locations in the European Columbus laboratory module. This provided baseline data points for the researchers, because when they returned to Earth, the researchers characterized the deposits on each surface and used the control material to establish a benchmark for the level and type of contamination. .

MatISS-2 had four identical sample holders containing three different types of material, installed in one location in Columbus. This study aimed to better understand how contamination spreads over time on hydrophobic (water repellent) and control surfaces. The improved Matiss-2.5 was set up to study how contamination spreads – this time in space – across hydrophobic surfaces using patterned samples. This experiment lasted a year and recently the samples were returned to Earth and are currently being analyzed.

Samples are made from a diverse blend of advanced materials, such as self-assembled monolayers, green polymers, ceramic polymers, and water-repellent hybrid silica. Smart materials should prevent bacteria from sticking and growing over large areas and making them easier to clean and more hygienic. The experiment hopes to determine which materials work best.

ESA says that “understanding the efficiency and potential use of these materials will be essential in the design of future spacecraft, especially those that carry the human father into space.

Long-term human space missions will certainly have to limit the biocontamination of astronaut habitats.

Learn more about the MatISS experience here.