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El grafito en un impacto del Apolo 17 derritió la 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
Resumen
Se encontraron grafito cristalino y bigotes de grafito (GW) en muestras lunares, lo que sugiere que los eventos de impacto crean estas estructuras. Este descubrimiento indica que la Luna conserva carbono antiguo del período del Bombardeo Pesado Tardío.
Área de la Ciencia:
- * Geología y geoquímica lunares.
- * Cosmoquímica y ciencia de los astromateriales.
- * Ciencias planetarias y cráteres de impacto.
Sus antecedentes:
- * Los whiskers de grafito (GW) son nuevas nanoestructuras de carbono con aplicaciones potenciales.
- * Comprender sus mecanismos de formación es crucial para la ciencia de los materiales y la exploración planetaria.
- * Estudios anteriores no han vinculado definitivamente la formación de GW con eventos de impacto extraterrestre.
Objetivo del estudio:
- * Para identificar y caracterizar materiales carbonosos dentro de muestras lunares.
- * Para investigar el origen del grafito y los GW encontrados en una breccia de fusión de impacto del Apolo 17.
- * Explorar el papel de los procesos de impacto en la formación de nanoestructuras de carbono en el sistema solar.
Principales métodos:
- * Examen microscópico de una muestra de breccia de la fusión del impacto del Apolo 17.
- * Análisis de grafito cristalino y grafit whiskers (GWs) utilizando técnicas avanzadas de imágenes.
- * Análisis del contexto geoquímico para descartar la contaminación terrestre.
Principales resultados:
- * Detección de granos discretos de grafito cristalino y GWs dentro de la muestra lunar.
- * La asociación espacial de grafito y GWs sugiere un origen común dentro de la muestra.
- * La ausencia de indicadores de contaminación terrestre apoya un origen lunar in situ.
Conclusiones:
- * Los procesos de impacto son un mecanismo plausible para la generación de GW en el sistema solar.
- * La Luna sirve como un depósito de material carbonoso antiguo del Bombardeo Pesado Tardío.
- * Este hallazgo amplía nuestra comprensión del ciclo del carbono en los cuerpos celestes.
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