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Una característica astronómica de 2175 angstrom en las partículas de polvo interplanetario
John Bradley1, Zu Rong Dai, Rolf Erni
1Institute of Geophysics and Planetary Physics, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA. jbradley@igpp.ucllnl.org
Science (New York, N.Y.)
|January 18, 2005
Resumen
La característica de extinción de 2175 angstrom del medio interestelar se identifica en las partículas de polvo interplanetario. El carbono orgánico y los silicatos amorfos son los portadores probables, lo que explica su longitud de onda consistente.
Área de la Ciencia:
- La astronomía y la astrofísica.
- Estudios del polvo cósmico Estudios del polvo cósmico
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- La característica de extinción de 2175 angstrom es una firma espectral prominente del polvo interestelar.
- Su origen y la identidad de los componentes responsables del polvo siguen siendo objeto de debate después de décadas de investigación.
Objetivo del estudio:
- Para investigar los portadores responsables de la extinción interestelar de 2175 Angstrom. característica. para investigar los portadores responsables de la extinción interestelar de 2175 Angstrom. característica. para investigar los portadores responsables de la extinción interestelar de 2175 Angstrom. característica. para investigar los portadores responsables de la extinción interestelar de 2175 Angstrom.
- Para analizar la composición de los granos interestelares dentro de las partículas de polvo interplanetario (IDP).
Principales métodos:
- Utilizó microscopía electrónica de transmisión (TEM) para examinar los granos interestelares.
- Analizó las propiedades espectrales de los componentes del polvo dentro de los PDI.
Principales resultados:
- Se ha detectado la característica de 5,7 electrones-voltios (2175 angstroms) en los granos interestelares dentro de las PDI.
- Identificó el carbono orgánico y los silicatos amorfos como los principales portadores de esta característica.
- Se observó que estos portadores son comunes tanto en los PDI como en el medio interestelar.
Conclusiones:
- El carbono orgánico y los silicatos amorfos se identifican como los principales portadores de la característica de extinción interestelar angstrom 2175.
- La presencia de múltiples portadores proporciona una explicación plausible para la longitud de onda central invariante y el ancho de banda variable de la característica.
- Este hallazgo avanza en nuestra comprensión de la composición del polvo interestelar y sus propiedades espectrales.
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