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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Comparación del polvo del cometa 81P/Wild 2 con el polvo interplanetario de los cometas
Hope A Ishii1, John P Bradley, Zu Rong Dai
1Institute of Geophysics and Planetary Physics, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA. hope.ishii@llnl.gov
Science (New York, N.Y.)
|January 26, 2008
Resumen
La misión Stardust fue la misión Stardust.
Área de la Ciencia:
- Cosmoquímica es la cosmoquímica.
- Ciencias planetarias Ciencias planetarias.
- La astrofísica es la astrofísica.
Sus antecedentes:
- La misión Stardust recogió muestras del cometa 81P/Wild 2.
- Se esperaba que el polvo cometario se asemejara a las partículas de polvo interplanetario chondrítico poroso.
- Se cree que estas partículas se originan en cometas.
Objetivo del estudio:
- Para analizar la composición del cometa 81P/Wild 2 se tomaron muestras.
- Para comparar los materiales cometarios con las partículas de polvo interplanetario (IDP).
- Comprender el origen y la evolución de los materiales del sistema solar.
Principales métodos:
- Análisis de muestras cometarias devueltas de la misión Stardust.
- Examen petrográfico y mineralógico de los materiales devueltos.
- Comparación con las composiciones conocidas de IDPs porosos condríticos y meteoritos.
Principales resultados:
- Los materiales silicatos clave que se encuentran en los IDP porosos condríticos están ausentes en las muestras de cometas.
- Las muestras de cometas están compuestas predominantemente de materiales de la nebulosa solar interna.
- La composición del material cometario se asemeja a la de los meteoritos condríticos del cinturón de asteroides.
Conclusiones:
- Es probable que el material nativo de la nebulosa externa sea raro en el cometa 81P/Wild 2.
- Existe un continuo petrogenético entre los cometas y los asteroides.
- Las partículas de polvo interplanetario porosas condríticas estratosféricas son cruciales para el estudio de los astromateriales primitivos.
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