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Espectrómetro de masas de iones y neutros de Cassini: Composición y estructura de la pluma de Encelado
J Hunter Waite1, Michael R Combi, Wing-Huen Ip
1Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, MI 48109, USA.
Science (New York, N.Y.)
|March 11, 2006
Resumen
La Cassini también es Cassini.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- La astroquímica es astroquímica.
- Exploración del espacio Exploración espacial
Sus antecedentes:
- La luna de Saturno Encélado exhibe una pluma atmosférica sustancial.
- Comprender la composición del penacho es clave para la habitabilidad de Encélado.
Objetivo del estudio:
- Para analizar la composición del penacho de Encelado durante un sobrevuelo cercano.
- Para identificar las fuentes del penacho.
Principales métodos:
- Se utilizaron datos del espectrómetro de masas iónicas y neutras (INMS) de la nave espacial Cassini.
- Se analizó la densidad y distribución del gas durante una aproximación cercana a Encelado.
Principales resultados:
- El penacho está compuesto principalmente de agua, con un importante contenido de dióxido de carbono y metano.
- Se detectaron una especie no identificada (relación masa-carga 28) y hidrocarburos en trazas.
- El amoníaco estaba presente en menos del 0,5%.
Conclusiones:
- La composición del penacho sugiere una fuente significativa cerca de la capa polar sur.
- La evidencia indica fuentes tanto localizadas como potencialmente globales para el penacho.
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