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Cometa yanaka (1988r): una nueva clase de cometa pobre en carbono
Science (New York, N.Y.)
|September 25, 1992
Resumen
El cometa Yanaka (1988r) muestra agotamientos químicos inusuales, que carecen de emisiones de carbono comunes como C2 y CN. Este hallazgo desafía los modelos de formación del sistema solar y los orígenes de los cometas de las nubes interestelares.
Área de la Ciencia:
- * Astronomía y Astrofísica.
- * Ciencia de los cometas.
- * Astroquímica es la astroquímica.
Sus antecedentes:
- * Se observan los cometas para determinar su composición química.
- * El cometa Yanaka (1988r) fue observado en enero de 1989.
- * Los cometas típicos exhiben emisiones de Ol, NH2, C2 y CN.
Objetivo del estudio:
- * Para analizar la composición química del cometa Yanaka (1988r).
- * Para investigar el agotamiento inusual de especies moleculares específicas en el cometa.
- * Para evaluar las implicaciones de estos hallazgos para los modelos de origen cometario.
Principales métodos:
- * Observación espectroscópica del cometa Yanaka (1988r) en enero de 1989.
- * Análisis de espectros de emisión para identificar especies moleculares.
- * Comparación de las emisiones observadas con las de los cometas típicos.
Principales resultados:
- * El cometa Yanaka (1988r) mostró emisiones de Ol y NH (2).
- * No se detectaron emisiones de C2 o CN, lo que indica un agotamiento significativo.
- * El cometa está agotado en C2 por al menos 100 veces y CN por 25 veces en comparación con los cometas típicos.
Conclusiones:
- * La composición del cometa Yanaka (1988r) es muy inusual en comparación con otros cometas.
- * Si los cometas se originan en nubes interestelares, este cometa puede ser un intruso de una nube químicamente distinta.
- * Si se formó en el sistema solar, la uniformidad de la nebulosa solar puede ser sobreestimada por los modelos de formación actuales.
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