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Venus: emisividad de radio de la superficie global
Science (New York, N.Y.)
|June 24, 1983
Resumen
Los datos del mapeador de radar Pioneer Venus revelan variaciones en la emisividad de la superficie de Venus vinculadas a la conductividad eléctrica. La baja emisividad en las regiones montañosas sugiere inclusiones de material conductor en la roca superficial.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- La geofísica es la geofísica.
- La radioastronomía es una radioastronomía.
Sus antecedentes:
- Las propiedades de la superficie de Venus son cruciales para comprender su historia geológica.
- El mapeo por radar proporciona información sobre la composición y la estructura de la superficie.
Objetivo del estudio:
- Para analizar las variaciones de emisión de radio térmica en la superficie de Venus.
- Para correlacionar la emisividad con la reflectividad del radar e inferir la composición de la superficie.
Principales métodos:
- Utilizó los datos del mapeador de radar Pioneer Venus.
- Emisión de radio térmica observada a una longitud de onda de 17 centímetros.
- Analizó las variaciones de emisividad a través del terreno venusiano.
Principales resultados:
- Las variaciones de la emisividad superficial fueron el principal impulsor de los cambios observados en la emisión de radio.
- La emisividad más baja (0.54 +/- 0.05) se encuentra en las tierras altas de Aphrodite Terra y Theia Mons.
- Estas regiones de baja emisividad se correlacionan con la alta reflectividad de radar previamente reportada.
Conclusiones:
- Las inclusiones de material altamente conductor eléctrico se infieren en la roca superficial de las tierras altas de Venus.
- Las variaciones de emisividad proporcionan un nuevo método para sondear las propiedades del subsuelo.
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