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Un componente reducido de carbono orgánico en el basalto marciano
A Steele1, F M McCubbin, M Fries
1Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road, NW, Washington, DC 20015, USA. asteele@ciw.edu
Science (New York, N.Y.)
|May 26, 2012
Resumen
El carbono macromolecular abiótico (MMC) se encontró en la mayoría de los meteoritos marcianos, lo que indica que los magmas marcianos precipitaron especies reducidas de carbono. Este descubrimiento es clave para entender el ciclo del carbono de Marte y la búsqueda de vida pasada.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- La geoquímica es la geoquímica.
- Astrobiología Astrobiología.
Sus antecedentes:
- El origen y la forma del carbono en Marte siguen siendo en gran medida desconocidos.
- Comprender el carbono marciano es crucial para las investigaciones astrobiológicas.
Objetivo del estudio:
- Para investigar la presencia y la naturaleza del carbono en los meteoritos marcianos.
- Para determinar el contexto geológico del carbono en Marte.
Principales métodos:
- Se empleó espectroscopia de imágenes Raman confocal.
- El análisis se realizó en 11 meteoritos marcianos que cubren 4.200 millones de años de historia marciana.
Principales resultados:
- Las fases abióticas de carbono macromolecular (CMM) se detectaron en 10 de los 11 meteoritos.
- Se encontró MMC asociado con granos de óxido dentro de minerales de alta temperatura.
- Se identificaron hidrocarburos aromáticos policíclicos en el meteorito Dar al Gani 476.
Conclusiones:
- Los magmas marcianos preferentemente precipitaron especies de carbono reducido durante la cristalización.
- La presencia generalizada de carbono orgánico abiótico en las rocas ígneas marcianas impacta nuestra comprensión del ciclo del carbono marciano.
- Estos hallazgos tienen implicaciones significativas para futuras misiones que busquen evidencia de vida marciana en el pasado.
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