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Dinámica de la magnetosfera de Saturno desde el MIMI durante la inserción orbital de Cassini
S M Krimigis1, D G Mitchell, D C Hamilton
1Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA. tom.krimigis@jhuapl.edu
Science (New York, N.Y.)
|February 26, 2005
Resumen
La Cassini también es Cassini.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Física del espacio Física del espacio
- Física de la magnetosfera Física de la magnetosfera Física de la magnetosfera Física de la magnetosfera Física de la magnetosfera Física de la magnetosfera Física de la magnetosfera
Sus antecedentes:
- El Instrumento de Imágenes Magnetosféricas (MIMI) de la nave espacial Cassini estudió la magnetosfera de Saturno antes y después de la inserción en órbita.
- La actividad de partículas energéticas se observó con frecuencia en el espacio interplanetario antes de la inserción en órbita de Saturno (SOI).
Objetivo del estudio:
- Para analizar las señales de átomo neutro energético (ENA) de la magnetosfera de Saturno.
- Para caracterizar la composición y la dinámica de la magnetosfera de Saturno utilizando datos MIMI.
Principales métodos:
- Utilizó el Instrumento de Imágenes Magnetosféricas (MIMI) a bordo de la nave espacial Cassini.
- Se han observado emisiones de átomos energéticamente neutros (ENA) de la magnetosfera de Saturno.
- Se realizan mediciones in situ de las concentraciones de iones dentro de la magnetosfera.
Principales resultados:
- Una señal ENA persistente fue detectada desde la magnetosfera de Saturno a aproximadamente 0,43 unidades astronómicas.
- La magnetosfera mostró una asimetría periódica de día y noche de 11 horas antes de SOI.
- Se midieron altas concentraciones de H+, H2+, O+, OH+ y H2O+, con bajas concentraciones de N+.
- Se identificó un cinturón de radiación hacia el interior del anillo D, probablemente formado por el intercambio de carga doble.
Conclusiones:
- Las imágenes de la ENA revelaron un cinturón de radiación previamente no caracterizado dentro de la magnetosfera de Saturno.
- Las densidades de gas neutro son suficientes para causar una pérdida significativa de iones en la magnetosfera interna y media.
- Los hallazgos proporcionan información sobre las complejas interacciones dentro de la magnetosfera de Saturno y su exosfera.
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