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Modelado del núcleo y los chorros del cometa 81P/Wild 2 basado en los datos del encuentro con Stardust
Zdenek Sekanina1, Donald E Brownlee, Thanasis E Economou
1Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA. zs@sek.jpl.nasa.gov
Science (New York, N.Y.)
|June 19, 2004
Resumen
Los datos de la nave espacial Stardust revelan que los chorros de núcleos de cometas se originan en puntos brillantes y pendientes específicos, no uniformemente. Estos chorros forman finas láminas de eyección, lo que sugiere fuentes de emisión localizadas en el núcleo giratorio.
Área de la Ciencia:
- * Ciencias planetarias Ciencias planetarias
- * Ciencia de los cometas.
- * Análisis de las misiones espaciales.
Sus antecedentes:
- * La comprensión de las propiedades del núcleo del cometa es crucial para las teorías de formación del sistema solar.
- * Los chorros cometarios son un mecanismo primario para la liberación y actividad de material.
Objetivo del estudio:
- * Para interpretar las propiedades del núcleo y la actividad de los chorros utilizando datos de la nave espacial Stardust.
- * Para identificar los orígenes y características de los chorros y las eyecciones cometarias.
Principales métodos:
- * Análisis de imágenes de la nave espacial Stardust y datos del sistema de monitoreo de polvo.
- * Triangulación de 20 chorros observados para determinar sus orígenes.
- * Correlación de las fuentes de chorro con la topografía del núcleo y las características de la superficie.
Principales resultados:
- * Se observaron dos chorros que emanan del lado oscuro del núcleo.
- * Dieciséis chorros se originaron en laderas donde la elevación solar excedió las predicciones.
- * Siete fuentes de chorro, incluidas cinco en la depresión de Mayo, coincidieron con manchas brillantes en la superficie.
- * Los datos de impacto de polvo indicaron que la nave espacial atravesó hojas de eyección delgadas y densas.
Conclusiones:
- * Los chorros cometarios se originan en fuentes específicas y localizadas en el núcleo, a menudo manchas brillantes.
- * La distribución de eyección observada es consistente con un modelo de cono de emisión de estas fuentes.
- * La topografía nuclear y la iluminación solar juegan un papel clave en la formación y actividad de los chorros.
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