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Espectro infrarrojo de la fría enana marrón Gl 229B
B R Oppenheimer1, S R Kulkarni, K Matthews
1Palomar Observatory, California Institute of Technology, Pasadena 91125, USA.
Science (New York, N.Y.)
|December 1, 1995
Resumen
El análisis espectroscópico de la enana marrón Gl 229B revela metano, similar a Júpiter pero no a las estrellas. Esto indica una temperatura superficial por debajo de 1000 K, confirmando que es más fría que cualquier estrella conocida.
Área de la Ciencia:
- La astronomía y la astrofísica.
- Ciencia exoplanetaria Ciencia de los exoplanetas.
Sus antecedentes:
- Las enanas marrones son objetos subestelares, lo que plantea desafíos para la clasificación.
- Las observaciones anteriores carecían de una caracterización atmosférica detallada de las enanas marrones frías.
Objetivo del estudio:
- Para analizar espectroscópicamente la atmósfera de la fría enana marrón Gl 229B.
- Para determinar la composición atmosférica y la temperatura de Gl 229B.
Principales métodos:
- Se empleó espectroscopia de infrarrojo cercano para medir las características de absorción.
- Comparación de datos espectrales con objetos celestes conocidos, incluyendo Júpiter y las estrellas.
Principales resultados:
- Se detectaron características de absorción atribuidas al metano en el espectro de Gl 229B.
- Estas características de metano son análogas a las observadas en Júpiter, no en las estrellas típicas.
- Las firmas de vapor de agua también indican una temperatura de superficie significativamente baja.
Conclusiones:
- Gl 229B posee metano, lo que confirma su naturaleza fría.
- Se estima que la temperatura de la superficie de Gl 229B está por debajo de 1000 Kelvin.
- Gl 229B representa un cuerpo celeste más frío que cualquier estrella conocida anteriormente.
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