K-State Geology undergrad has “out-of-this-world” internship
What did you do with your summer vacation? Well K-State Geology undergrad, Sarah Lamm, had an experience that was out of this world! She had the opportunity to work as a summer intern at Los Alamos National Laboratory (LANL) alongside planetary scientist, Dr. Nina Lanza, on the ChemCam team. The ChemCam is an instrument on the Curiosity Mars Rover and it can determine rock compositions by using laser pulses to excite rock material into a plasma. As the plasma cools, it releases light at characteristic wavelengths. The goal of her work was to learn more about the manganese oxide minerals the rover found on the martian surface.
On Earth, this family of manganese-bearing minerals marks an important shift in the Earth’s environment ~2.3 billion years ago. Manganese oxides do not show up in Earth’s geological record until the atmosphere became oxygenated after the rise of photosynthetic organisms. Manganese oxides can only form in specific redox environments with both liquid water and strongly oxidizing conditions—or where microorganisms catalyze their precipitation. Thus, their presence on Mars suggests that the planet’s atmosphere was once more oxygenated than previously thought. However, whether microorganisms helped form martian manganese oxides is unclear. The team is conducting further research to examine chemical and mineralogical clues about the origin of these minerals on Mars.
During her summer internship, Lamm used ChemCam to track the change of abundance of manganese across the full traverse of Curiosity, with a focus on the last half of the traverse. She assessed over 7237 acquired over ~1000 sols (martian days) of the mission looking for major and minor elemental relationships that might coincide with occurrences of high manganese. By mapping the spatial distribution of manganese abundance across the traverse, Lamm found that the highest abundances of Mn appear mainly in one geological formation. However, high Mn was found in a diverse range of rock types, including sandstone, conglomerates, and even within a calcium sulfate vein. Her results suggest that most high manganese materials have been incorporated into local rocks primarily as sediments, rather than forming in situ.
Lamm has presented the results of her research at the LANL Student Symposium, the Department of Geology’s Open House, and the Midwest Regional Meeting of the American Chemical Society (held locally in Manhattan this year). Lamm was a co-author on a talk at the fall meeting of the American Geophysical Union in San Francisco, CA. She will present a poster on her results at the upcoming 48th Lunar and Planetary Scientific Conference in Houston, TX in March.
While at K-State, she is continuing her efforts in Dr. Kirk’s laboratory, where she is growing manganese oxides with different strains of microorganisms to examine how biological conditions affect the properties of the resultant minerals. This summer, she will take the oxides she generates here at K-State back to LANL and analyze their compositions using the ChemCam engineering model as part of her second internship.