The Moon serves as a natural archive of early geological history of the Earth-Moon system. Unaltered lunar material offers a window into the events that occurred nearly four billion years ago. Using advanced electron microscopy and spectroscopy techniques, we can characterize the structure and composition of lunar minerals at an atomic level to uncover chemical environment present on the ancient Moon.

We studied the mineral ilmenite from an Apollo 17 rock and found that the ilmenite itself is enriched in titanium. We find that the excess titanium is found in a trivalent valence state as opposed to the tetravalent state. The reduced valence state only occurs in oxygen-poor environments, which we estimated using the abundance of trivalent titanium.

STEM/EELS @ U.S. Naval Research Laboratory.
NASA Solar System Exploration Research Institute (SSERVI):

Solar wind ions and electrons continuously bombard the surface of airless bodies, resulting in structural and compositional alterations. We irradiate terrestrial ilmenite to simulate the solar wind and characterize the induced formation of nanophase iron (npFe) and its associated microscopic changes using electron microscopy.

As charged particles irradiate the surface of airless bodies, the minerals accumulate the charge and can eventually lead to a repulsive force between mineral grains. We simulate the charge accumulation within intergrain micro-cavities using a kinetic Monte Carlo approach by connecting the microscopic scattering events to the macroscopic surface charge.

NASA Solar System Exploration Research Institute (SSERVI):

Our goal is to advance the development of radiation shielding materials by incorporating exploring polymers suitable for additive manufacturing, optimizing shielding structures, and investigating radiation-induced damage. To specifically address:

1. How can shielding composites be optimized to reduce the radiation exposure of occupational workers?
2. How do the manufactured composites compare with the simulation predictions?
3. How does the associated radiation damage affect the structural and optical properties of the composites?

We simulated composite shielding materials incorporating hexagonal boron nitride (hBN) into a high-density polyethylene (HDPE) matrix and evaluated their neutron attenuation performance using Geant4 Monte Carlo simulations. Optimized hBN/HDPE composites reduced th effective dose by up to 72× compared to aluminum shields. Improvements are relevant to both astronauts in space exploration and terrestrial environments such as medical facilities.

Former NASA Solar System Exploration Research Institute (SSERVI) called the Radiation Effects on Volatiles and Exploration of Asteroids and Lunar Surfaces (REVEALS)

Space plasma instruments typically use a time-of-flight (TOF) mass spectrometers to measure the compositions of charge particles in solar, space, and planetary science. A notable TOF instrument is the NASA Van Allen Probes instrument called HOPE (Helium, Oxygen, Proton, and Electron), developed at Los Alamos National Laboratory, which successfully measured the particle fluxes in Earth's radiation belts.

We developed models to predict TOF mass spectrometer resolution and characterized ultrathin graphene foils for next-generation detectors, improving calibration fidelity for magnetospheric particle measurements while exploring graphene's potential.

Internal funding sources at Los Alamos National Laboratory.