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Diamantes en densas nubes moleculares: un desafío al paradigma estándar del medio interestelar
L J Allamandola1, S A Sandford, A G Tielens
1National Aeronautics and Space Administration, Ames Research Center, Mountain View, CA 94035.
Science (New York, N.Y.)
|April 2, 1993
Resumen
El polvo interestelar en las nubes densas muestra una firma única similar al diamante, a diferencia de los grupos CH2 y CH3 que se encuentran en las nubes difusas. Este descubrimiento desafía los modelos existentes de formación y evolución del material interestelar.
Área de la Ciencia:
- La astroquímica es astroquímica.
- Física del medio interestelar Física del medio interestelar
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- La composición del polvo interestelar varía entre las regiones densas y difusas.
- Las moléculas orgánicas en el polvo juegan un papel crucial en la evolución química.
- Estudios anteriores no han caracterizado completamente el componente orgánico en las densas nubes interestelares.
Objetivo del estudio:
- Para investigar la composición orgánica del polvo interestelar en las densas nubes.
- Para comparar las firmas orgánicas en medios interestelares densos y difusos.
- Comprender las vías de formación de los materiales orgánicos interestelares.
Principales métodos:
- Espectroscopia infrarroja para detectar bandas de estiramiento C-H.
- Análisis de las firmas espectrales del polvo interestelar.
- Comparación de datos de entornos interestelares densos y difusos.
Principales resultados:
- Se descubrió una nueva banda de estiramiento infrarroja C-H, indicativa de material similar al diamante en densas nubes.
- El polvo en el medio interestelar difuso se caracteriza por grupos -CH2- y -CH3.
- Existe una dicotomía significativa en el componente orgánico alifático entre los medios densos y difusos.
Conclusiones:
- La presencia de material interestelar similar al diamante en nubes densas desafía los modelos estándar de los procesos interestelares.
- Este hallazgo descarta ciertos modelos para la formación de diamantes meteoríticos.
- La formación de este material similar al diamante está probablemente relacionada con procesos interestelares comunes o tipos estelares.
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