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Composición y propiedades físicas de la superficie de Encelado
Robert H Brown1, Roger N Clark, Bonnie J Buratti
1Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA.
Science (New York, N.Y.)
|March 11, 2006
Resumen
La Cassini también es Cassini.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Astrobiología Astrobiología.
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- La luna de Saturno Encélado exhibe composiciones de superficie únicas y anomalías térmicas.
- La región del polo sur, conocida como las "rayas de tigre", es de particular interés.
Objetivo del estudio:
- Para analizar la composición de la superficie y las propiedades térmicas de Encelado utilizando el espectrómetro de mapeo visual e infrarrojo (VIMS) de Cassini.
- Para investigar la presencia de moléculas clave y determinar los límites de temperatura en regiones específicas.
Principales métodos:
- Utilizó datos de tres sobrevuelos de Cassini de Encélado en 2005.
- Empleó el espectrómetro de mapeo visual e infrarrojo (VIMS) para el análisis espectral.
Principales resultados:
- La superficie de Encélado es predominantemente hielo de agua, con ligeros compuestos orgánicos y CO2 cerca del polo sur.
- Se establecieron límites superiores para el monóxido de carbono (CO) atmosférico a 5 nanómetros precipitables y el amoníaco (NH3) en depósitos superficiales al 2%.
- Las temperaturas en las regiones de la franja del tigre se limitaron a un límite superior de 140 Kelvin.
Conclusiones:
- La composición de la superficie de Encélado, especialmente las rayas de tigre, proporciona información sobre su actividad geológica.
- Los límites derivados para CO y NH3 ofrecen restricciones para los modelos atmosféricos y de superficie de Encélado.
- Los datos térmicos de las rayas de tigre sugieren fuentes o procesos de energía localizados.
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