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La actividad y el tamaño del núcleo del cometa Hale-Bopp (C/1995 O1) [ver comentario]
H A Weaver1, P D Feldman, M F A'Hearn
1Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA.
Science (New York, N.Y.)
|March 28, 1997
Resumen
El cometa Hale-Bopp fue descubierto.
Área de la Ciencia:
- La astronomía y la astrofísica.
- Ciencia de la ciencia de los cometas.
Sus antecedentes:
- El análisis de las imágenes del Telescopio Espacial Hubble (HST) indica que el diámetro del núcleo del cometa Hale-Bopp es de 27 a 42 km, significativamente mayor que el del cometa P/Halley.
- Los datos espectroscópicos del HST y el International Ultraviolet Explorer (IUE) revelaron las emisiones del sistema OH, CS y CO Cameron, rastreando H2O, CS2 y CO2 respectivamente.
Objetivo del estudio:
- Para analizar las imágenes del Telescopio Espacial Hubble (HST) del cometa Hale-Bopp.
- Para determinar el tamaño del núcleo y la composición del cometa Hale-Bopp.
- Investigar las tasas de producción de varias especies y su relación con la distancia heliocéntrica.
Principales métodos:
- Análisis de imágenes del Telescopio Espacial Hubble (HST) para estimar el diámetro del núcleo.
- Análisis espectroscópico utilizando el Explorador Internacional de Ultravioleta y el HST para detectar emisiones de OH, CS y CO.
- Correlación de las tasas de producción de agua (H2O), disulfuro de carbono (CS2) y polvo con la distancia heliocéntrica.
Principales resultados:
- El diámetro del núcleo del cometa Hale-Bopp se estima entre 27 y 42 km, significativamente más grande que el cometa P/Halley.
- Se detectaron emisiones de OH (agua), CS (disulfuro de carbono) y CO (dióxido de carbono).
- La variación heliocéntrica de la producción de H2O se alinea con la sublimación del cuerpo helado, pero las tasas de producción de CS2 y polvo muestran diferentes dependencias.
Conclusiones:
- El cometa Hale-Bopp posee un núcleo sustancialmente grande.
- La sublimación del agua es un factor primario para la producción de H2O, pero no el único factor para la producción de CS2 y polvo.
- Se necesita más investigación para comprender los complejos procesos que rigen la desgasificación y la liberación de polvo cometario.
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