Powerful microscopic techniques and instruments are used by scientists to study meteorites, gathering important data on their structure and composition. By combining transmission electron microscopy (TEM), energy-dispersive x-ray spectroscopy (EDS) and electron energy-loss spectroscopy (EELS), previous studies have yielded a plethora of information about extraterrestrial carbonaceous materials (such as presolar graphite grains), which in turn provide insight into the evolution of the Solar System.

However, the powerful electron beams used in such studies can damage carbon-rich materials. A recent study reports data from a new analysis using low-voltage STEM, EDS, and EELS. Low accelerating voltages allowed for detailed data to be collected on five presolar graphite spherules, one grain from the LAP 031117 meteorite, and four acid residue grains from the Murchison meteorite.

The study, “Low-Voltage Energy-Dispersive X-ray Spectroscopy and Electron Energy-Loss Spectroscopy Analysis of Presolar Graphite Spherules,” was published in Microscopy and Microanalysis. The work was supported by the Nexus for Exoplanet System Science (NExSS). NExSS is a NASA research coordination network supported in part by the NASA Astrobiology Program. This program element is shared between NASA’s Planetary Science Division (PSD) and the Astrophysics Division.