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Published on: October 3, 2020
¿Qué es lo que perturba los enormes anillos de Urano?
Science (New York, N.Y.)
|January 31, 1986
Resumen
Las grandes perturbaciones en Urano.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- La astronomía es la astronomía.
- La Dinámica Orbital es una Dinámica Orbital.
Sus antecedentes:
- Urano posee nueve anillos conocidos, con los anillos gamma y delta exhibiendo perturbaciones radiales significativas.
- Estos dos anillos se desvían de las órbitas keplerianas predecibles, mostrando residuos de raíz media cuadrada de aproximadamente 3 kilómetros, a diferencia de los otros siete anillos.
Objetivo del estudio:
- Para investigar las causas de las grandes perturbaciones radiales en los anillos gamma y delta de Urano.
- Para analizar los patrones de perturbación en busca de evidencia de resonancias de Lindblad e identificar posibles satélites pastores.
Principales métodos:
- Se examinaron los patrones de perturbación de los anillos gamma y delta para las resonancias de Lindblad (m=0, 1, 2, 3, 4).
- Residuos radiales analizados del anillo beta para la coincidencia de resonancia.
- Evaluó la probabilidad de que la resonancia sea causada por la inestabilidad viscosa frente a factores externos.
Principales resultados:
- Los residuos radiales del anillo beta se alinean bien con una resonancia de Lindblad de 2: 1, lo que sugiere un satélite sin descubrir.
- Este satélite potencial orbita alrededor de Urano a 76.522 +/- 8 km con un período de 15.3595 +/- 0.0001 horas y un radio de 75-100 km.
- Ninguna resonancia Lindblad de orden bajo coincide con las perturbaciones del anillo gamma, lo que indica que es probable que sean causadas por grandes satélites pastores.
Conclusiones:
- Una resonancia de Lindblad de 2:1 sugiere fuertemente un satélite no descubierto cerca del anillo beta, detectable por la Voyager.
- Es probable que las perturbaciones del anillo gamma sean causadas por uno o más grandes satélites pastores, visibles en las imágenes de la Voyager.
- Es poco probable que la resonancia para el anillo beta provenga de la inestabilidad viscosa debido a su ubicación relativa al anillo delta.
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