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Evidencia de materiales altamente reflectantes en la superficie y el subsuelo del vensus
Science (New York, N.Y.)
|May 20, 1988
Resumen
Los materiales de alta reflectividad de Fresnel, que superan el 50 por ciento, están presentes en la superficie y el subsuelo de Venus. Este descubrimiento, basado en datos de radar, sugiere que estos materiales pueden estar muy extendidos, incluso por debajo de las regiones de llanuras.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Radar Astronomía y Astronomía por el Radar
- La geofísica es la geofísica.
Sus antecedentes:
- Venus exhibe diversas características de superficie y composiciones.
- Las observaciones anteriores de radar proporcionaron información limitada sobre el subsuelo.
- Comprender las propiedades de los materiales superficiales y subterráneos es crucial para los estudios de evolución planetaria.
Objetivo del estudio:
- Para investigar la reflectividad de Fresnel de los materiales de la superficie y el subsuelo de Venus.
- Para identificar regiones con alta reflectividad e inferir propiedades del material.
- Para evaluar la distribución y el origen de estos materiales reflectantes.
Principales métodos:
- Análisis de datos de radar de longitud de onda de 12,5 centímetros obtenidos por el interferómetro de radar Goldstone (1980, 1986).
- Integración de imágenes de radar lunar y datos de Venera 15 y 16.
- Interpretación de la retrodispersión de radar para determinar la reflectividad de Fresnel.
Principales resultados:
- Evidencia de reflectividad de Fresnel superior al 50 por ciento en materiales de superficie y subsuelo.
- Alta reflectividad confirmada en las regiones montañosas.
- Presencia potencial de material de alta reflectividad debajo de las llanuras, excavado por cráteres de impacto.
Conclusiones:
- Una porción significativa de la superficie y el subsuelo superficial de Venus se caracteriza por un material altamente reflectante.
- Estos hallazgos sugieren una amplia distribución de materiales o estructuras específicas que influyen en la reflectividad del radar.
- Los cráteres de impacto pueden desempeñar un papel en la exposición de estas capas reflectantes subterráneas en áreas llanas.
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