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Evidencia de metamorfismo térmico en los asteroides C, g, B y f
Science (New York, N.Y.)
|August 20, 1993
Resumen
La mayoría de los asteroides C, G, B y F probablemente tienen superficies térmicamente metamorfoseadas. Las condritas carbonáceas calentadas, particularmente los meteoritos CM2, coinciden estrechamente con los espectros de reflexión de los asteroides, lo que sugiere composiciones e historias de superficie similares.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- La espectroscopia es una técnica de espectroscopia.
- La mineralogía es la Mineralogía.
Sus antecedentes:
- La clasificación de los asteroides se basa en las propiedades espectrales.
- Las condritas carbonáceas son meteoritos originados en asteroides.
- Comprender la composición de la superficie de los asteroides es clave para los estudios de formación del sistema solar.
Objetivo del estudio:
- Para comparar los espectros de reflexión de asteroides y condritas carbonáceas.
- Para identificar posibles análogos para las composiciones de la superficie de los asteroides.
- Para investigar el procesamiento térmico de las superficies de asteroides.
Principales métodos:
- Adquisición y análisis de espectros de reflectancia (0,3 2,6 micrómetros).
- Comparación de espectros de 14 asteroides C, G, B y F con 21 polvos de condrita carbonáceos.
- Calentamiento experimental de la condrita Murchison CM2 para simular el metamorfismo térmico.
Principales resultados:
- Tres condritas CM-Cl térmicamente metamorfoseadas mostraron una débil absorción ultravioleta, coincidiendo con algunos asteroides.
- La condrita CM2 de Murchison calentada (6001000°C) coincidía estrechamente con los espectros promedio de los asteroides C y G.
- El análisis de la absorción ultravioleta indicó un metamorfismo térmico (6001000°C) para la mayoría de los asteroides estudiados.
Conclusiones:
- Ciertas condritas carbonáceas, especialmente las alteradas térmicamente, son análogos viables para algunos asteroides de tipo C, G, B y F.
- Es probable que los minerales de la superficie de los asteroides hayan sufrido un metamorfismo térmico significativo.
- Las comparaciones espectroscópicas proporcionan información sobre la historia térmica y la composición de las superficies de los asteroides.
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