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El polvo interestelar. polvo interestelar. Evidencia de origen interestelar de siete partículas de polvo recogidas
Andrew J Westphal1, Rhonda M Stroud2, Hans A Bechtel3
1Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA, USA. westphal@ssl.berkeley.edu.
Science (New York, N.Y.)
|August 16, 2014
Resumen
Siete partículas de polvo interestelar recogidas por la misión Stardust muestran diversas composiciones, que difieren de los modelos actuales. El análisis distinguió estas partículas cósmicas de los escombros de naves espaciales.
Área de la Ciencia:
- Análisis del polvo cósmico.
- Investigación del medio interestelar en el medio interestelar.
- Ciencias planetarias Ciencias planetarias.
Sus antecedentes:
- La misión Stardust tenía como objetivo recolectar y devolver muestras de polvo interestelar.
- Comprender la composición del polvo interestelar proporciona información sobre los orígenes y la evolución del sistema solar.
- Distinguir entre el polvo interestelar y los escombros de naves espaciales que orbitan la Tierra es crucial para un análisis preciso.
Objetivo del estudio:
- Para analizar las partículas devueltas por el colector de polvo interestelar Stardust.
- Identificar y caracterizar las partículas de polvo interestelar candidatas.
- Para comparar las propiedades de las partículas recogidas con los modelos existentes de polvo interestelar.
Principales métodos:
- Análisis de laboratorio de siete partículas capturadas.
- Identificación de más de 50 partículas de desechos de naves espaciales.
- Análisis de composición elemental y trayectoria de impacto para diferenciar los orígenes de las partículas.
Principales resultados:
- Siete partículas exhibieron características consistentes con un origen interestelar.
- Los candidatos al polvo interestelar se distinguían claramente de los escombros de las naves espaciales.
- Las partículas interestelares identificadas mostraron una diversidad significativa en la composición elemental, estructura cristalina y tamaño.
- Algunas partículas contenían granos cristalinos y múltiples fases portadoras de hierro, incluidos los sulfuros.
Conclusiones:
- Las partículas analizadas proporcionan evidencia directa de que el polvo interestelar contemporáneo llegó a la Tierra.
- La diversidad observada en las partículas candidatas interestelares sugiere que los modelos actuales pueden ser demasiado simplistas.
- Estos hallazgos desafían los modelos teóricos y observacionales existentes de la composición del polvo interestelar.
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