EEPS graduate student Jack Henry has been awarded a prestigious NASA Future Investigators in NASA Earth and Space Science and Technology (FINESST) grant to do experiments and modeling to better understand the accuracy of LIBS (laser-induced breakdown spectroscopy), which is used to identify the compositions of materials on Mars, with a focus on the use of LIBS to understand loose materials like dust and sand instead of rocks. Accurately determining the composition of these granular materials using LIBS is important to answering outstanding questions about the chemical makeup of the crust and past habitability.
Henry’s research has implications not only for current instruments operating on Mars but for future planetary missions that are likely to employ LIBS as well as other fields that use the technique.
LIBS uses a pulsed laser to ablate the surface of a sample, creating a plasma of excited atoms and ions. The spectrum of the plasma contains information about the concentrations of various elements that make up a material’s composition. Because interactions between elements in plasma are complicated, a machine learning model is used to interpret chemical compositions from the spectrum. The machine learning models used on Mars were trained using homogenized rock pellets lased under Martian atmospheric conditions using analog instruments on Earth. Henry’s research will investigate how well those models work and how they can be improved when the material being investigated is a powder or granular material instead of a rock.
LIBS is a widespread technique and its use is not confined to planetary sciences. It is commonly applied in life sciences, industrial metallurgical and mining processes, and even in the monitoring of carbon levels in soils. Henry’s research should not only help improve LIBS measurements and machine learning models on Mars, but has much wider potential to improve analyses of other types of granular materials.
“LIBS has proven to be a versatile technique. It’s energy efficient, it's fast and we can easily apply this for investigating similar size-fraction [if different composition] materials on other planets such as the Moon and Titan,” says Henry. “I want to figure out how LIBS can handle a variety of environments and situations that right now, it doesn't because it's not quite there yet.”
The FINESST research grant provides up to $150,000 over three years for graduate student-designed and performed research projects that contribute to NASA’s Science Mission Directorate's science, technology, and exploration goals. The funding can be used for tuition, travel, research materials, and stipend.
Unlike other NASA grants, the student participant (Future Investigator) defines the FINESST project and must be the primary author of the research proposal.
“This project was absolutely directed by Jack—he discovered unexpected trends in LIBS data from Mars and convinced me, then our collaborators, and now NASA proposal reviewers that the material properties are likely affecting our LIBS results,” says faculty advisor Dr. Kirsten Siebach, adding that the FINESST acceptance rate for applicants is only about 10 percent.
Henry’s proposal was one of the 55 selected proposals out of 431 submitted to the Planetary Science Division of the NASA FINESST program in 2024.
“Jack is very good at combing through complex datasets and creating visualizations that reveal trends that no one else has recognized—it’s exciting to meet each week and see what else he has found. I’m thrilled NASA saw that as well and awarded funds to ensure he can pursue this creative, novel, and important work," says Siebach.
L. Welzenbach
EEPS Science Communications