Una lluvia de polvo del Mioceno tardío de la ruptura de un asteroide en el cinturón principal
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Updated: May 9, 2026
09:44
Laboratory Drop Towers for the Experimental Simulation of Dust-aggregate Collisions in the Early Solar System
Published on: June 5, 2014
Kenneth A Farley1, David Vokrouhlický, William F Bottke
1Division of Geological and Planetary Sciences, California Institute of Technology, MS 170-25, Pasadena, California 91125, USA. farley@gps.caltech.edu
Nature
|January 20, 2006
Resumen
Una importante colisión de asteroides hace 8,3 millones de años aumentó significativamente las partículas de polvo interplanetario (IDP) que llegan a la Tierra. Los registros de helio-3 (3He) del fondo marino revelan este evento, mostrando un aumento de cuatro veces en el flujo de IDP de los fragmentos de la familia Veritas.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- La geoquímica es la geoquímica.
- Estudios del polvo cósmico Estudios del polvo cósmico
Sus antecedentes:
- La Tierra es bombardeada continuamente por partículas de polvo interplanetario (IDP), fragmentos de asteroides y cometas.
- El flujo de PDI es generalmente estable, con nuevas partículas reemplazando a las perdidas a través de varios procesos.
- Los IDP contienen helio-3 (3He), por lo que las concentraciones de 3He en el sedimento del fondo marino son un sustituto del flujo pasado de IDP.
Objetivo del estudio:
- Investigar los principales eventos que afectan el flujo de partículas de polvo interplanetario (IDP) y los cuerpos fuente a lo largo del tiempo geológico.
- Para analizar el impacto de las colisiones de asteroides en la tasa de acreción de IDP terrestre.
- Para correlacionar los registros del fondo marino con eventos astronómicos específicos.
Principales métodos:
- Análisis de las concentraciones de 3He en los sedimentos del fondo marino como un sustituto del flujo de IDP.
- Datación del evento de disrupción de la familia de asteroides Veritas.
- Comparación de los datos de flujo de IDP con los datos orbitales de asteroides y otros registros geológicos.
Principales resultados:
- La interrupción de la colisión de la familia de asteroides Veritas, hace ~8,3 millones de años, causó un aumento transitorio en el flujo de IDP.
- El flujo de desplazados internos alcanzó su punto máximo en aproximadamente cuatro veces los niveles anteriores al evento y duró alrededor de 1,5 millones de años.
- Los fragmentos de la familia Veritas dominaron la tasa de acreción de PDI terrestre durante el Mioceno tardío.
Conclusiones:
- Las colisiones de asteroides pueden alterar significativamente y temporalmente el flujo de partículas de polvo interplanetario que llega a la Tierra.
- Los registros de 3He del fondo marino proporcionan una herramienta valiosa para reconstruir las variaciones de flujo de IDP pasadas e identificar los principales eventos del sistema solar.
- Un evento similar, aunque incierto, se registra en el registro 3He hace 35 millones de años.
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