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Detección por radar del núcleo y el coma del cometa hyakutake
1J. K. Harmon, National Astronomy and Ionosphere Center, Arecibo Observatory, Post Office Box 995, Arecibo, PR 00614, USA. S. J. Ostro, L. A. M. Benner, K. D. Rosema, R. F. Jurgens, R. Winkler, D. K. Yeomans, D. Choate, R. Cormier, J. D. Giorg.
Science (New York, N.Y.)
|December 24, 1997
Resumen
Las observaciones de radar revelaron el cometa Hyakutake.
Área de la Ciencia:
- * Ciencias planetarias Ciencias planetarias
- * La astronomía es la ciencia.
- * Ciencia de los cometas.
Sus antecedentes:
- * El cometa Hyakutake (C/1996 B2) es un cometa brillante observado con el radar.
- * Estudios previos sobre núcleos cometarios y composición del coma interno.
Objetivo del estudio:
- * Para determinar el tamaño del núcleo del cometa Hyakutake.
- * Investigar la composición y la dinámica del coma interno.
- * Para entender la relación entre la actividad cometaria y el tamaño.
Principales métodos:
- * Observaciones por radar en el Complejo de Comunicaciones Espaciales Profundas de Goldstone.
- * Análisis de ecos de radar desde el núcleo y el coma interno.
- * Modelado de la retrodispersión de los granos cometarios.
Principales resultados:
- * El núcleo del cometa Hyakutake se estima en 2-3 kilómetros de diámetro.
- * Los ecos de radar indican retrodispersión de granos porosos del tamaño de un centímetro.
- * Los granos expulsados anisotrópicamente a decenas de metros por segundo.
Conclusiones:
- * La actividad cometaria puede no reflejar con precisión el tamaño de un cometa.
- * Los granos grandes son un factor significativo en la pérdida de masa de los cometas activos.
- * Las observaciones por radar proporcionan información sobre la estructura y evolución de los cometas.
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