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Probando el campo magnético solar con un cometa que se acerca al Sol
Cooper Downs1, Jon A Linker, Zoran Mikií
1Predictive Science Inc., San Diego, CA 92121, USA. cdowns@predsci.com
Resumen
El cometa C/2011 W3 (Lovejoy) reveló los campos magnéticos de la corona solar. Sus movimientos de cola, observados a través de imágenes ultravioletas extremas, proporcionaron datos para distinguir entre los modelos de campo magnético.
Área de la Ciencia:
- Física solar Física solar es la física de la energía solar.
- Ciencia de la ciencia de los cometas.
- La física del plasma es la física del plasma.
Sus antecedentes:
- El cometa C/2011 W3 (Lovejoy) atravesó la corona solar en diciembre de 2011.
- Esta región es en gran parte inexplorada por las naves espaciales.
- Las observaciones ultravioletas extremas capturaron cambios dinámicos en la cola del cometa.
Objetivo del estudio:
- Para analizar el comportamiento de la cola del cometa dentro de la corona solar.
- Para utilizar estas observaciones para comprender el campo magnético de la corona solar.
- Para diferenciar entre varios modelos de campo magnético solar.
Principales métodos:
- Modelado magnetohidrodinámico combinado (MHD) de la corona solar.
- Modelado el movimiento de los iones de la cola de un cometa dentro del plasma solar.
- Se analizaron datos de imágenes en ultravioleta extrema (UVE) de la cola del cometa Lovejoy.
Principales resultados:
- Se observaron variaciones significativas en la dirección de la cola del cometa, su intensidad, magnitud y persistencia.
- Los movimientos de las colas de los cometas indicaban un campo magnético no homogéneo en la corona solar.
- Propiedades restringidas del campo solar y del plasma a lo largo de la trayectoria del cometa.
Conclusiones:
- La interacción del cometa Lovejoy con la corona solar proporciona una sonda única de su entorno magnético.
- La dinámica de la cola observada ofrece un método para distinguir entre diferentes modelos de campos magnéticos solares.
- Este estudio pone de relieve el valor de los sobrevuelos cometarios para la investigación de la física solar.
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