Galileo orbiter ultraviolet observations of Jupiter aurora
Galileo orbiter ultraviolet observations of Jupiter aurora
复制标题
伽利略轨道飞行器对木星极光的紫外线观测
DOI：
10.1029/98je00832
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发表时间：
1998
影响因子：
--
通讯作者：
B. Sandel
中科院分区：
文献类型：
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作者：
J. Ajello;D. Shemansky;W. Pryor;K. Tobiska;C. Hord;S. K. Stephens;I. Stewart;J. Clarke;K. Simmons;W. McClintock;C. Barth;J. Gebben;Deborah A. Miller;B. Sandel
1996年，在伽利略号卫星的头四次轨道飞行中，伽利略紫外线分光仪（1130 - 4320 A）和极紫外线分光仪（540-1280 A）几乎同时观测了南极和北极地区的木星极光。这些观测被模拟以提供来自H2 Rydberg系统（B，B '，B，C，D，D' → X波段系统）的极光的绝对表面亮度。极紫外极光的光谱分布和亮度对H2丰度、H2温度和CH 4丰度敏感。发射光谱分析表明，极紫外极光（800-1200 A）产生于1016 - 1020 cm-2或更高的H2斜柱丰度所对应的高度范围内。1130 ~ 1700 A的远紫外（FUV）光谱在H2中是光学薄的，但对CH 4柱丰度和二次电子能量分布非常敏感。从FUV光谱模型中发现的CH 4吸收体的斜柱丰度在0 - 10 × 1016 cm-2的范围内变化，表明在同层顶或以上的高空极光和深极光都存在。FUV谱在1520 A附近有C2 H2吸收带.对于2000 km宽的椭圆形，H2里德堡系统极光的表面亮度为100 ~ 600 kR，H莱曼α极光的表面亮度为60 ~ 130 kR。由粒子沉积输入大气的总功率估计为10.1 × 10 ~（14）W。
In 1996 during the first four orbits of the satellite tour the Galileo ultraviolet spectrometer (UVS) (11304320 A) and extreme ultraviolet spectrometer (EUVS) (540-1280 A) performed near-simultaneous observations of the Jupiter aurora in both the north and south polar regions. These observations are modeled to provide the absolute surface brightness of the aurora from the H 2 Rydberg Systems (B, B', B, C, D, D' → X band systems). The spectral distribution and brightness of the EUV aurora are sensitive to H 2 abundance, H 2 temperature, and CH 4 abundance. Analysis of the emission spectra indicates that the EUV aurora (800-1200 A) are produced over a range of altitudes corresponding to slant column abundances of H 2 from 10 16 to 10 20 cm -2 or greater. The UVS spectra of the far ultraviolet (FUV) from 1130 to 1700 A are optically thin in H 2 , but highly sensitive to the CH 4 column abundance and to the secondary electron energy distribution. The slant column abundance of CH 4 absorbers found from models of the FUV spectra varied in the range 0 - 10 x 10 16 cm -2 , indicating the presence of both high altitude aurora, at or above the homopause, and deep aurora. The FUV spectra show C 2 H 2 absorption bands near 1520 A. The surface brightness of the aurora from the H 2 Rydberg Systems ranged from 100 to 600 kR and of H Lyman α was 60 to 130 kR for a 2000 km wide oval. The total power input to the atmosphere from particle deposition is estimated to be ∼ 1 X 10 14 W.