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El descubrimiento de huellas de núcleos en el polvo interplanetario
Science (New York, N.Y.)
|December 21, 1984
Resumen
Las huellas nucleares encontradas en las partículas de polvo interplanetario confirman su origen extraterrestre. Las altas densidades de las pistas sugieren una exposición al sistema solar interior, lo que ayuda a distinguir los micrometeoritos prístinos de los modificados.
Área de la Ciencia:
- Análisis del polvo cósmico Análisis del polvo cósmico
- Ciencias planetarias Ciencias planetarias.
- La geofísica es la geofísica.
Sus antecedentes:
- Las partículas de polvo interplanetario (IDP) son materiales extraterrestres que se encuentran en la Tierra.
- Comprender su origen e historia es crucial para los estudios de evolución del sistema solar.
- Las pistas nucleares pueden proporcionar información sobre la exposición espacial y la entrada atmosférica de estas partículas.
Objetivo del estudio:
- Identificar y analizar las huellas nucleares en los PDI recolectados estratosféricamente.
- Para confirmar la naturaleza extraterrestre de los desplazados internos utilizando pruebas de rastro.
- Para determinar la edad de exposición y el historial térmico de los PDI.
Principales métodos:
- Recopilación de partículas de polvo interplanetario de la estratosfera.
- Análisis microscópico para identificar y cuantificar las huellas nucleares dentro de los PDI.
- Cálculo de las densidades de las vías para estimar edades de exposición y límites térmicos.
Principales resultados:
- Se identificaron inequívocamente las huellas nucleares en los PID estratosféricos.
- Las densidades de las vías oscilaron entre 10 y 11 por centímetro cuadrado.
- Esto indica una edad de exposición de aproximadamente 10~4) años en el sistema solar interior.
Conclusiones:
- Las huellas nucleares proporcionan la prueba definitiva del origen extraterrestre de los desplazados internos.
- Los hallazgos sugieren un período de exposición significativo dentro del sistema solar interior.
- El análisis de las pistas ofrece un método para establecer los límites superiores de temperatura durante la entrada en la atmósfera, diferenciando los micrometeoritos prístinos de los modificados.
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