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Los orígenes de los asteroides cercanos a la Tierra
Science (New York, N.Y.)
|August 7, 1992
Resumen
Los asteroides cercanos a la Tierra (NEAs) se reponen por asteroides del cinturón principal, según una nueva investigación. Las propiedades físicas de los pequeños asteroides del cinturón principal se parecen mucho a las NEAs, lo que apoya esta teoría del origen.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Investigación de asteroides y cometas.
Sus antecedentes:
- Los asteroides cercanos a la Tierra (NEAs) tienen vidas dinámicas cortas y requieren reposición.
- Dos fuentes hipotéticas para los NEA son los asteroides del cinturón principal y los núcleos de cometas extintos.
- Distinguir entre estas fuentes es un desafío debido a las dificultades para medir las propiedades físicas de pequeños (D < 5 km) asteroides del cinturón principal y núcleos de cometas.
Objetivo del estudio:
- Para comparar las propiedades físicas de los pequeños asteroides del cinturón principal con las de los NEAs.
- Para evaluar la contribución de los asteroides del cinturón principal frente a los núcleos de cometas a la población de la NEA.
Principales métodos:
- Realizó un nuevo estudio de las propiedades físicas de los asteroides del cinturón principal con diámetros menores a 5 kilómetros.
- Analizó la velocidad de giro y las distribuciones de la forma de estos asteroides del cinturón principal.
- Comparó estas distribuciones con los datos conocidos para las NEA y los datos disponibles para los núcleos de cometas.
Principales resultados:
- La velocidad de giro y las distribuciones de forma de los pequeños asteroides del cinturón principal son similares a las de los NEAs.
- Esta similitud apoya fuertemente un origen del cinturón principal para la mayoría de los NEAs.
- El análisis de datos limitados de núcleos de cometas sugiere que los núcleos de cometas constituyen entre el 0% y el 40% de la población total de NEA.
Conclusiones:
- Las características físicas de los pequeños asteroides del cinturón principal son consistentes con que sean la fuente principal para reponer los asteroides cercanos a la Tierra.
- La contribución de núcleos de cometas extintos a la población de NEA es probablemente limitada, según los datos actuales.
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