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Hielo de agua expuesto en el núcleo del cometa 67P/Churyumov-Gerasimenko
G Filacchione1, M C De Sanctis1, F Capaccioni1
1INAF-IAPS, Istituto di Astrofisica e Planetologia Spaziali, Rome, Italy.
Nature
|January 14, 2016
Resumen
Los científicos encontraron granos de hielo de agua del tamaño de un milímetro en los escombros caídos en el cometa 67P/Churyumov-Gerasimenko. Estos hallazgos sugieren que los procesos evolutivos formaron recubrimientos complejos, no necesariamente una estratificación global de la formación.
Área de la Ciencia:
- Ciencia de los cometas
- Ciencias planetarias
- Astrobiología
Sus antecedentes:
- El vapor de agua es abundante en el coma del cometa 67P/Churyumov-Gerasimenko, y el hielo de agua es un componente importante de los núcleos cometarios.
- Las regiones de hielo de agua expuestas en las superficies cometarias rara vez se observan, con núcleos típicamente recubiertos de material deshidratado, refractario y rico en orgánico.
Objetivo del estudio:
- Para identificar y caracterizar el hielo de agua en la superficie del cometa 67P/Churyumov-Gerasimenko.
- Investigar los mecanismos de formación y las implicaciones de los granos de hielo de agua observados.
Principales métodos:
- La espectroscopia infrarroja se usó para detectar hielo de agua en regiones específicas del núcleo del cometa.
- Se realizó un análisis cuantitativo para determinar la abundancia y el tamaño de los granos de hielo de agua.
Principales resultados:
- Se identificó hielo de agua en las caídas de escombros dentro de la región de Imhotep, expuesto en las paredes y en sus bases.
- Se detectaron granos de hielo de agua pura de tamaño milimétrico, significativamente más grandes que los observados anteriormente.
- La presencia de estos granos grandes sugiere la formación a través de la difusión de vapor en capas ricas en hielo o sinterización.
Conclusiones:
- La distribución de hielo de agua observada y el tamaño del grano indican procesos evolutivos dentro de los metros superiores del núcleo.
- Los núcleos cometarios pueden desarrollar recubrimientos complejos con costras deshidratadas sobre capas enriquecidas con hielo.
- Estos hallazgos desafían la necesidad de una estratificación global desde el momento de la formación cometaria para explicar la estratigrafía observada.
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