New Protective Coating Heading to ISS for Study
A coating developed by a Florida International University lab to protect equipment on the lunar surface from radiation is scheduled to be studied on the International Space Station this fall. A sample of the coating will be mounted outside the facility for exposure to space, then analyzed for its resistance to radiation.
About the Research
FIU’s Plasma Forming Laboratory from the College of Engineering and Computing reportedly developed an innovative coating material to shield structures, such as rovers or excavation tools, against radiation levels up to 1,000 times greater than on Earth.
The research comes as NASA’s Artemis Program plans to build the first-ever base camp on the lunar surface. Radiation on the moon can interrupt signal processing in electronics and shorten the service life of structures.
“By attaching the material to the International Space Station, we can get close to simulating the real radiation that structures will face on the moon,” said Professor Arvind Agarwal, Chair of the Mechanical and Materials Engineering Department and Director of the Plasma Forming Lab.
The coating sample will be placed directly facing the sun on the ISS. FIU and NASA scientists will both watch closely for how the coating changes temperature as the space station orbits Earth. After six months, a crew of astronauts will take the material back to Earth for analysis.
FIU's Plasma Forming Lab developed a new coating to protect machinery for use on the lunar surface against the harsh elements of space. ???— FIU Engineering & Computing (@FIU_CEC) August 23, 2022
Read more at FIU News.https://t.co/IvkNpXM3Sj
??: David Drucker@NASAArtemis @FIUmecheng
“Our team selected direct exposure to the sun because we want to be very harsh on our coatings,” said Sara Rengifo, a materials engineer at NASA who is working with Agarwal on the research.
Back at the laboratories, the material will then be tested for its durability against lunar dust, tiny shards of rock found on the moon’s surface.
FIU reports that NASA expects the findings to benefit future missions, with the resulting data potentially reducing service and repair needs. Additionally, the research could yield commercial implications in industries where materials face harsh conditions, such as in nuclear waste containment and hypersonic vehicles production.
The research is reportedly a collaboration between public and private entities, with FIU as the principal academic partner. Six students are working on the project, including four interns.
Recent ISS Coatings Research
At the beginning of the year, polymer coatings research conducted by the University of Idaho was launched and installed at the International Space Station, with hopes to minimize bacterial transmission. The university was one of five selected through NASA’s Student Payload Opportunity with Citizen Science (SPOCS) nationwide competition.
The coatings were tested on an aluminum alloy used in high-contact areas throughout the ISS, such as handrails and door handles, to test how microgravity affects the efficacy of the polymers known to resist bacteria adhesion on Earth.
The U of I students submitted a proposal for SPOCS funding in October 2020 as part of their research conducted in fall 2020 as a senior capstone project assigned by Associate Professor Matthew Bernards.
As part of the NASA funding, the team was expected to involve K-12 students in their research. According to U of I, the two polymers selected by trail to go to the ISS were led by the students with over two hundred third- through fifth-grade students at J. Russell Elementary School in Moscow, Idaho.
Researchers refined a non-toxic gel solution containing the bacteria-resistant polymers in petri dishes, and then asked the elementary students to get creative when collecting bacteria. Some of the samples came from sinks, floors, windows, lunch tables, keyboards or hand sanitizer bottles.
Then, the students used a nutrient broth to grow the bacteria in the petri dishes over the next 30 days. After monitoring daily changes, the students reported the two polymers they believed were the best candidates, and the research team analyzed their data to verify those results.
The engineering students also had to design a housing to prevent bacteria from growing before it reaches spaces. Bernards said that the team was limited to a 10-by-10-by-15-centimeter container that could weigh no more than 1.5 kilograms, otherwise less than approximately 3.4 pounds.
NASA also limited the amount of electricity, noise and vibrations allowed for the chemistry to work, with the project needing as little involvement as possible from the astronauts aboard the ISS.
To achieve this, the container holds an upper dry space for electronic storage and a lower wet space for bacteria growth and a set of motorized devices to introduce bacteria. When plugged in, the bacteria encapsulated in a small spring-loaded plunger are introduced into the wet chamber to initiate growth
According to U of I, the device also contains control plates with no polymer coating.
The research was installed onboard the ISS by astronaut Kayla Barron and was scheduled to remain undisturbed for 30 days before being returned to the university for final evaluations and report, including microscopy assessment to determine which polymer best resisted bacteria.
More recently, in June, the European Space Agency announced that it was studying materials for self-cleaning antimicrobial coatings to protect both astronauts and materials on the International Space Station. The ESA’s Materials’ Physical and Chemistry Section is working in collaboration with the Istituto Italiano di Tecnologia.
The PATINA project, or “Optimization of Photo-catalytic Antibacterial coatings,” was proposed through the ESA’s Open Space Innovation Platform, which seeks novel ideas for space research. According to the release, the project also covers other antimicrobial surface treatments, including super-hydrophobic materials that repel all moisture, electro-static reaction and biocide-releasing materials.
A microbial survey of surfaces on the ISS reportedly found dozens of different bacteria and fungi species, including pathogens such as Staphylococcus aureus which can cause skin and respiratory infections as well as food poisoning. Biofilms from theses microbial populations can also tarnish and eat away at metla, glass, plastic and rubber on the spacecraft.
The ISS’s predecessor, the Mir space station, reportedly experienced this issue when microbial colonies were observed growing on spacesuits, cable insulation and the seals of windows.
To combat this, the IIT team started working with titanium oxide, or titania, which is used in self-cleaning glass or hygienic surfaces on Earth. When exposed to ultraviolet light, the material breaks down water vapor in the air into “free oxygen radicals” that eat bacterial membranes. Titanium oxide has previously been used for antimicrobial coatings in hospitals, but the researchers are looking at methods to change the compound to increase its sensitivity to the visible portion of the light spectrum.
According to the ESA, the coating was successfully tested on glass, silicon wafer, aluminum foil and clean-room grade paper tissue. This testing was completed through a variety of methods, including physical vapor deposition and atomic layer deposition.
The ESA adds that its research complements existing European research such as the French space-surface experiment MATISS and the German Touching Surfaces experiment investigating bacterial growth aboard the ISS.
Recent Artemis Awards
Earlier this year, in March, NASA announced the selection of three university-led proposals for the development of technologies for living and working on the Moon. The selection of projects arrives as NASA prepares to return astronauts to space for long-term exploration with Artemis.
According to NASA, the proposals awarded for the research will look into the extraction of lunar resources, autonomous construction methods and developing electronics capable of working under the Moon's extremely cold temperatures.
Each proposal was selected under the second Lunar Surface Technology Research (LuSTR) solicitation and aims to harness the creativity of the nation's university researchers to cultivate technologies for lunar infrastructure. LuSTR is part of NASA's Space Technology Research Grants program, which supports groundbreaking research in advanced space technology by academic researchers.
Tasked with the goal of developing robots capable of completing construction projects, such as building habitats and landing pads, is The Colorado School of Mines. This effort is being led by principal investigator Christopher Dreyer, who plans to develop tools and methods for autonomous construction on the Moon's surface.
While construction will be an important aspect of staying on the Moon for long periods of time, NASA has realized that sending supplies from Earth will be expensive and time-consuming. It is that reason that they have awarded Missouri University of Science and Technology for in-situ resource utilization. For this research, led by principal investigator Leslie Gertsch, teams will work to develop magnetic and electrostatic technologies for extracting and efficiently separating calcium- and aluminum-containing minerals from the Moon's soil, also called regolith.
Another obstacle that astronauts will have to face while working on the Moon is the planet’s extremely cold temperatures, which have been reported to plummet hundreds of degrees Fahrenheit below zero at night or within cratered areas that never see direct sunlight. Auburn University, led by principal investigator Michael Hamilton, has been awarded for the development of new electronics that are highly reliable and tolerant of low temperatures.
Each team will receive up to $2 million, awarded as grants, over two years to develop their proposed technologies.