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Materia orgánica capturada desde el cometa 81P/Wild 2 por la nave espacial Stardust
Scott A Sandford1, Jérôme Aléon, Conel M O'd Alexander
1Astrophysics Branch, NASA-Ames Research Center, Moffett Field, CA 94035, USA. ssandford@mail.arc.nasa.gov
Science (New York, N.Y.)
|December 16, 2006
Resumen
Las muestras del cometa 81P/Wild 2 revelan diversos compuestos orgánicos, algunos con orígenes interestelares. Estos compuestos orgánicos extraterrestres muestran composiciones únicas, diferentes de los meteoritos y el polvo interplanetario.
Área de la Ciencia:
- Cosmoquímica es la cosmoquímica.
- Astrobiología Astrobiología.
- Ciencias planetarias Ciencias planetarias.
Sus antecedentes:
- Las muestras de cometas proporcionan información sobre el inventario químico del sistema solar temprano.
- Comprender la composición de los compuestos orgánicos cometarios es crucial para la astrobiología y los orígenes de la vida.
Objetivo del estudio:
- Para caracterizar la composición orgánica del cometa 81P/Wild 2 se tomaron muestras.
- Para comparar los compuestos orgánicos cometarios con otros materiales extraterrestres como meteoritos y partículas de polvo interplanetario.
- Investigar el patrimonio potencial y las vías de formación de estos compuestos orgánicos.
Principales métodos:
- Análisis de muestras devueltas del cometa 81P/Wild 2.
- Análisis químico e isotópico detallado de moléculas orgánicas.
- Análisis comparativo con las bases de datos existentes de composiciones orgánicas de polvo meteorítico e interplanetario.
Principales resultados:
- Los compuestos orgánicos cometarios exhiben una distribución heterogénea y una composición desequilibrada.
- Los orgánicos son ricos en oxígeno y nitrógeno, con un menor contenido aromático en comparación con los meteoritos y los IDP.
- Los excesos de deuterio y nitrógeno-15 sugieren orígenes interestelares / protoestelares para algunos compuestos.
- Se identificó una clase distinta de material orgánico pobre en aromáticos.
Conclusiones:
- El cometa 81P/Wild 2 contiene un conjunto diverso de compuestos orgánicos identificables.
- Estos compuestos orgánicos poseen características únicas, incluidas anomalías isotópicas, que apuntan a historias de formación complejas.
- Los hallazgos contribuyen a comprender la entrega de moléculas prebióticas a la Tierra primitiva.
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