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Dos envolturas independientes y primitivas del núcleo bilobado del cometa 67P
Matteo Massironi1,2, Emanuele Simioni3, Francesco Marzari4
1Dipartimento di Geoscienze, University of Padova, via G. Gradenigo 6, 35131 Padova, Italy.
Nature
|September 30, 2015
Resumen
El cometa 67P/Churyumov-Gerasimenko
Área de la Ciencia:
- Ciencias planetarias
- Ciencia de los cometas
- Formación del sistema solar
Sus antecedentes:
- Los factores de formación de los núcleos de los cometas siguen siendo en gran medida desconocidos.
- La forma bilobada del cometa 67P/Churyumov-Gerasimenko sugiere una posible fusión o excavación.
- Comprender la estructura de los núcleos cometarios es clave para la evolución temprana del Sistema Solar.
Objetivo del estudio:
- Para investigar la composición estructural y la formación del núcleo bilobado del cometa 67P/Churyumov-Gerasimenko.
- Para determinar si el núcleo es un solo cuerpo formado o una acumulación de múltiples objetos.
- Para arrojar luz sobre los procesos primordiales en el sistema solar temprano.
Principales métodos:
- Análisis de envolturas estratificadas en los lóbulos mayor y menor del cometa 67P.
- Cálculo de los vectores de gravedad para los lóbulos individuales y todo el núcleo.
- Comparación de los vectores de gravedad con la orientación de los estratos observados.
Principales resultados:
- El lóbulo mayor del cometa 67P tiene una envoltura estratificada distinta, separada del lóbulo menor.
- Los vectores de gravedad se alinean perpendicularmente a los estratos cuando los lóbulos se analizan de forma independiente.
- El núcleo exhibe una estratificación "similar a la cebolla", lo que indica la formación previa a la fusión de objetos distintos.
Conclusiones:
- El cometa 67P/Churyumov-Gerasimenko es un cuerpo acumulado formado por dos cometasimales distintos.
- Estos cometasimales sufrieron colisiones suaves y de baja velocidad al principio del Sistema Solar.
- Las similitudes en la estructura del lóbulo sugieren procesos de acreción estratificados primordiales comparables para cometesimales independientes.
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