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Observaciones del espectrómetro ultravioleta de Neptuno y el tritón
Science (New York, N.Y.)
|December 15, 1989
Resumen
La atmósfera superior de Neptuno alcanza los 750 grados Kelvin, con un espectro ultravioleta similar al de otros gigantes gaseosos. La atmósfera de Tritón es principalmente de nitrógeno con una presión superficial de 14 microbars.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Física de la atmósfera Física de la atmósfera
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- Comprender la composición atmosférica y la estructura térmica de los planetas exteriores es crucial para la planetología comparativa.
- Las observaciones anteriores de gigantes gaseosos proporcionaron una base para comparar las características atmosféricas de Neptuno.
Objetivo del estudio:
- Para determinar la temperatura y la composición atmosférica de Neptuno utilizando datos de ocultación solar.
- Para analizar el espectro ultravioleta de la atmósfera iluminada por el sol de Neptuno.
- Para investigar las propiedades atmosféricas de la luna de Neptuno, Tritón.
Principales métodos:
- Mediciones de ocultación solar para inferir la temperatura y composición atmosférica.
- Espectroscopia ultravioleta y ultravioleta extrema para analizar las emisiones atmosféricas.
- Observaciones de resplandor de aire para la caracterización de la atmósfera de Tritón.
Principales resultados:
- La temperatura de la atmósfera superior de Neptuno se estima en 750 +/- 150 grados Kelvin.
- Distribución de metano, acetileno y etano determinada en la atmósfera baja de Neptuno.
- El espectro ultravioleta de Neptuno está dominado por H Lyman alfa y las emisiones de hidrógeno molecular, similares a las de Júpiter, Saturno y Urano.
- Escala de emisiones ultravioleta extrema con el cuadrado inverso de la distancia heliocéntrica.
- La atmósfera de Tritón se identificó como principalmente nitrógeno molecular con trazas de metano, una temperatura de 95 +/- 5 kelvins y una presión superficial de aproximadamente 14 microbars.
Conclusiones:
- Las propiedades atmosféricas de Neptuno se alinean con las de otros planetas gigantes en términos de emisiones espectrales.
- Las observaciones de la Voyager proporcionan una escala consistente de las emisiones UV en todo el sistema solar exterior.
- Tritón posee una tenue atmósfera de nitrógeno y metano.
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