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Identificación de dos fuentes de monóxido de carbono en el cometa Hale-Bopp
M A DiSanti1, M J Mumma, N Dello Russo
1Department of Physics, The Catholic University of America, Washington, DC 20064, USA. disanti@kuiper.gsfc.nasa.gov
Nature
|June 29, 1999
Resumen
El cometa Hale-Bopp fue descubierto.
Área de la Ciencia:
- La astronomía y la astrofísica.
- Ciencias planetarias Ciencias planetarias.
- La astroquímica es astroquímica.
Sus antecedentes:
- La composición del hielo cometario ofrece pistas sobre la formación del sistema solar.
- La abundancia de monóxido de carbono (CO) en relación con el agua indica el procesamiento de material precometario.
- Las mediciones anteriores de CO en el hielo cometario eran ambiguas.
Objetivo del estudio:
- Para determinar la abundancia nativa de CO en el hielo del cometa Hale-Bopp.
- Evaluar las implicaciones para el procesamiento químico del material precometario.
- Para diferenciar entre el CO originado en el núcleo frente al coma.
Principales métodos:
- Observaciones in situ del cometa Hale-Bopp.
- Análisis de la abundancia de CO2 en relación con el hielo de agua.
- Comparación con las composiciones de la nube molecular y la envoltura protoestelar.
Principales resultados:
- Aproximadamente el 50% del CO del cometa Hale-Bopp se origina directamente del hielo del núcleo.
- La proporción de CO-a-agua en el hielo es del 12%, más baja que en las nubes moleculares en reposo.
- Esta proporción se alinea con las abundancias encontradas en envolturas proto-estelares.
Conclusiones:
- Los hielos cometarios en Hale-Bopp muestran evidencia de procesamiento antes de la acreción.
- La abundancia de CO observada sugiere condiciones de formación en una envoltura proto-estelar.
- El procesamiento posterior en el coma probablemente explica el CO restante.
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