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Los bigotes de grafito en los meteoritos CV3
1Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road N.W., Washington, DC 20015, USA. Marc.D.Fries@jpl.nasa.gov
Science (New York, N.Y.)
|March 1, 2008
Resumen
Los bigotes de grafito (GW), un alotrópico de carbono, se encontraron en meteoritos, lo que sugiere que pueden existir en el espacio. Estos hallazgos impactan nuestra comprensión de los primeros materiales del sistema solar y las observaciones astronómicas.
Área de la Ciencia:
- Cosmoquímica es la cosmoquímica.
- Astrobiología Astrobiología.
- Ciencias planetarias Ciencias planetarias.
Sus antecedentes:
- Los bigotes de grafito (GWs) son un alótropo de carbono propuesto en el espacio.
- Su presencia en los meteoritos podría ofrecer información sobre las primeras condiciones del sistema solar.
Objetivo del estudio:
- Para investigar la presencia y el origen de los bigotes de grafito en los meteoritos.
- Para evaluar las posibles implicaciones astronómicas de los bigotes de grafito.
Principales métodos:
- Las imágenes de Raman.
- Microscopía electrónica con microscopía electrónica.
- Análisis de las condritas carbonáceas tipo CV.
Principales resultados:
- Los bigotes de grafito descubiertos en tres condritas carbonáceas tipo CV.
- Los GW están asociados con inclusiones de calcio-aluminio de alta temperatura (CAI) y conondrulas inusuales.
- La condensación de GW probablemente ocurrió temprano en la historia del sistema solar.
Conclusiones:
- Los bigotes de grafito pueden ser expulsados de los sistemas solares jóvenes al espacio interestelar.
- Los GW podrían influir en las observaciones astronómicas, incluida la atenuación de las supernovas y la termualización del fondo cósmico.
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