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La síntesis de compuestos orgánicos e inorgánicos en las estrellas evolucionadas
1Institute of Astronomy & Astrophysics, Academia Sinica, PO Box 23-141, Taipei 106, Taiwan. kwok@asiaa.sinica.edu.tw
Nature
|August 27, 2004
Resumen
Los granos pre-solares de estrellas evolucionadas se encuentran en meteoritos y polvo. Estos materiales estelares, incluidos los compuestos orgánicos, se forman rápidamente en el espacio y sobreviven a los viajes interestelares, contribuyendo significativamente al polvo cósmico.
Área de la Ciencia:
- Cosmoquímica es la cosmoquímica.
- La astroquímica es astroquímica.
- Evolución Estelar Evolución Estelar
Sus antecedentes:
- El análisis isotópico revela materiales en estado sólido pre-solares en meteoritos y polvo interplanetario.
- Estos granos inorgánicos se originan en las envolturas circunstelares de las estrellas evolucionadas.
Objetivo del estudio:
- Para rastrear el origen de los granos pre-solares.
- Para investigar la síntesis molecular en entornos circunstelares.
- Para evaluar la supervivencia y la contribución de los granos estelares al polvo interestelar.
Principales métodos:
- Análisis isotópico de meteoritos y polvo interplanetario.
- Detección de compuestos orgánicos en las nebulosas.
Principales resultados:
- Identificados materiales en estado sólido de origen pre-solar.
- Trazado granos inorgánicos a las envolturas de estrellas evolucionadas.
- Se han detectado compuestos orgánicos aromáticos y alifáticos en proto-planetas y nebulosas planetarias.
- Se ha observado una rápida síntesis molecular (cientos de años) en entornos circumestelares.
Conclusiones:
- Los granos estelares sobreviven a los viajes interestelares.
- Los granos estelares son un componente importante del polvo interestelar.
- Los entornos circumestelares son sitios activos para la síntesis molecular rápida.
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