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Updated: Jan 25, 2026
09:13
Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction
Published on: April 1, 2017
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Fine-grained Material Associated with a Large Sulfide returned from Comet 81P/Wild 2
Z Gainsforth1, A J Westphal1, A L Butterworth1
1Space Sciences Laboratory, University of California, Berkeley, CA 94720.
Meteoritics & Planetary Science
|May 14, 2019
Summary
Researchers discovered fine-grained material (FGM) on comet 81P/Wild 2, similar to interplanetary dust particles. This material, found with a sulfide particle, offers clues about cometary composition and early solar system heating events.
Area of Science:
- * Cosmochemistry and Planetary Science.
- * Analysis of extraterrestrial materials from comets.
Background:
- * The Stardust mission successfully returned samples from comet 81P/Wild 2.
- * Interplanetary dust particles (IDPs) provide insights into solar system formation and evolution.
- * Chondritic-porous IDPs (CP-IDPs) are a significant component of dust collected from comets.
Purpose of the Study:
- * To analyze a large particle returned from comet 81P/Wild 2.
- * To characterize fine-grained material (FGM) found in contact with a sulfide particle.
- * To compare the FGM with known components of CP-IDPs and investigate the sulfide's properties.
Main Methods:
- * Consortium analysis of a cometary sample returned by the Stardust spacecraft.
- * Microscopic and compositional examination of FGM and associated sulfide particle.
- * Comparison of observed characteristics with established data for GEMS and EAs.
Main Results:
- * Discovery of FGM in contact with a large sulfide particle within the comet sample.
- * Some FGM particles exhibit characteristics similar to glass with embedded metals and sulfides (GEMS) and equilibrated aggregates (EAs).
- * The sulfide particle contains Ni-rich lamellae, suggesting a post-formation heating event.
Conclusions:
- * The FGM represents components similar to those found in chondritic-porous interplanetary dust particles (CP-IDPs).
- * The presence of protected FGM suggests successful capture mechanisms in aerogel.
- * The Ni-rich lamellae in the sulfide indicate a potential long-duration heating event in the early solar system prior to cometary incorporation.
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