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Synthesis and Reaction Chemistry of Nanosize Monosodium Titanate
Published on: February 23, 2016
El lloviznazo matutino generalizado en Titán
Máté Adámkovics1, Michael H Wong, Conor Laver
1Department of Astronomy, University of California, Berkeley, CA 94611, USA. mate@berkeley.edu
Science (New York, N.Y.)
|October 13, 2007
Resumen
Los científicos han observado directamente lluvia de metano en la atmósfera de Titán por primera vez. Este descubrimiento revela la precipitación que se produce en el continente más brillante de la luna, Xanadu.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Ciencias de la atmósfera Ciencias atmosféricas.
- Astrobiología Astrobiología.
Sus antecedentes:
- Se sabe que la atmósfera de Titán tiene nubes de metano y se espera precipitación.
- La observación directa de la precipitación y su ubicación geográfica ha permanecido elusiva.
Objetivo del estudio:
- Para observar directamente y caracterizar la precipitación en la atmósfera de Titán.
- Para identificar las regiones geográficas y las condiciones asociadas con la lluvia de metano en Titán.
Principales métodos:
- Análisis de los espectros del infrarrojo cercano obtenidos por el Very Large Telescope (VLT) y los observatorios W. M. Keck.
- Recuperación de perfiles de extinción atmosférica para identificar el metano condensado y las lloviznas.
Principales resultados:
- Se observó una mayor opacidad atmosférica en la troposfera en el lado matutino de Titán.
- Evidencia consistente de nubes de metano cerca de 30 km de altitud y llovizna de metano por debajo.
- Humedad detectada sobre la región ecuatorial, específicamente por encima del continente Xanadu.
- Las nubes y la precipitación son ópticamente delgadas a 2,0 micrómetros, con tamaños de gotas de 0,1 mm o más.
Conclusiones:
- Este estudio proporciona la primera evidencia directa de la precipitación de metano en Titán.
- Los hallazgos sugieren que los gradientes de temperatura diurna, la humedad relativa del metano, los vientos y la topografía contribuyen a la condensación de metano y a la llovizna.
- Las nubes "subvisibles" observadas y la llovizna sobre Xanadu ofrecen nuevos conocimientos sobre el ciclo hidrológico de Titán.
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