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Updated: Jun 11, 2026
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Atom Probe Tomography Analysis of Exsolved Mineral Phases
Published on: October 25, 2019
Graphite in an Apollo 17 impact melt breccia.
A Steele1, F M McCubbin, M Fries
1Carnegie Institution of Washington, Geophysical Laboratory, 5251 Broad Branch Road N.W., Washington, DC 20015, USA. asteele@ciw.edu
Science (New York, N.Y.)
|July 3, 2010
Summary
Crystalline graphite and graphite whiskers (GWs) were found in lunar samples, suggesting impact events create these structures. This discovery indicates the Moon preserves ancient carbon from the Late Heavy Bombardment period.
Area of Science:
- * Lunar geology and geochemistry
- * Cosmochemistry and astromaterials science
- * Planetary science and impact cratering
Background:
- * Graphite whiskers (GWs) are novel carbon nanostructures with potential applications.
- * Understanding their formation mechanisms is crucial for materials science and planetary exploration.
- * Previous studies have not definitively linked GW formation to extraterrestrial impact events.
Purpose of the Study:
- * To identify and characterize carbonaceous materials within lunar samples.
- * To investigate the origin of graphite and GWs found in an Apollo 17 impact melt breccia.
- * To explore the role of impact processes in the formation of carbon nanostructures in the solar system.
Main Methods:
- * Microscopic examination of an Apollo 17 impact melt breccia sample.
- * Analysis of crystalline graphite and graphite whiskers (GWs) using advanced imaging techniques.
- * Geochemical context analysis to rule out terrestrial contamination.
Main Results:
- * Detection of discrete grains of crystalline graphite and GWs within the lunar sample.
- * Spatial association of graphite and GWs suggests a common origin within the sample.
- * Absence of terrestrial contamination indicators supports an in-situ lunar origin.
Conclusions:
- * Impact processes are a plausible mechanism for generating GWs in the solar system.
- * The Moon serves as a repository for ancient carbonaceous material from the Late Heavy Bombardment.
- * This finding expands our understanding of carbon cycling on celestial bodies.
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