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Synthesis and Microdiffraction at Extreme Pressures and Temperatures
Published on: October 7, 2013
Excesos extremos de deuterio en los micrometeoritos ultracarbónicos de la nieve de la Antártida central
J Duprat1, E Dobrică, C Engrand
1Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse, Université Paris-Sud 11, CNRS/IN2P3, F-91405 Orsay, France. jean.duprat@csnsm.in2p3.fr
Science (New York, N.Y.)
|May 8, 2010
Resumen
Los micrometeoritos ultracarbono que se encuentran en la nieve antártica contienen materia orgánica con un enriquecimiento extremo de deuterio (D). Estos materiales primitivos del sistema solar sugieren un origen en el frío disco protoplanetario.
Área de la Ciencia:
- Cosmoquímica es la cosmoquímica.
- Ciencias planetarias Ciencias planetarias.
- Astrobiología Astrobiología.
Sus antecedentes:
- El polvo interplanetario primitivo contiene componentes del sistema solar primitivo, incluidos minerales y materia orgánica.
- Comprender el origen y la composición de estos materiales es clave para desentrañar la formación del sistema solar.
- Estudios anteriores han analizado el polvo cometario, pero las muestras más grandes y prístinas son raras.
Objetivo del estudio:
- Para analizar la composición y el origen de los micrometeoritos ultracarbónicos recuperados de la nieve antártica.
- Para investigar el enriquecimiento de deuterio (D) y la mineralogía de la materia orgánica dentro de estos micrometeoritos.
- Para determinar la ubicación de la formación y el patrimonio (sistema solar vs. interestelar) de la materia orgánica.
Principales métodos:
- Recuperación de micrometeoritos ultracarbónicos de muestras de nieve de la Antártida central.
- Análisis de la materia orgánica para el enriquecimiento de deuterio (D) utilizando espectrometría de masas.
- Identificación de minerales cristalinos incrustados dentro de la materia orgánica del micrometeorito.
Principales resultados:
- Los micrometeoritos exhiben excesos extremos de deuterio (D) (10-30 veces los valores terrestres) en su materia orgánica.
- Los minerales cristalinos están incrustados dentro de la materia orgánica, lo que sugiere una formación in situ.
- Las masas de las partículas oscilan entre 0,1 y unos pocos microgramos, más grandes que las muestras de la misión Stardust.
Conclusiones:
- Las altas relaciones D/H, la abundante materia orgánica y los minerales asociados sugieren fuertemente un origen del sistema solar.
- Estos hallazgos favorecen un origen de las regiones frías del disco protoplanetario.
- Los micrometeoritos ultracarbónicos representan una muestra única y valiosa de material del Sistema Solar primitivo.
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