We present the first large-scale statistical survey of the Jovian main emission (ME) to map auroral properties from their ionospheric locations out into the equatorial plane of the magnetosphere, where they are compared directly to in-situ spacecraft measurements. We use magnetosphere-ionosphere (MI) coupling theory to calculate currents from the auroral brightness as measured with the Hubble Space Telescope and from plasma flow speeds measured in-situ with the Galileo spacecraft. The effective Pedersen conductance of the ionosphere remains a free parameter in this comparison. We calculate the Pedersen conductance from the combined data sets, and find it ranges from mho overall with averages of mho in the north and mho in the south. Considering the HST-derived field-aligned currents per radian of azimuth only, we find values of MA rad⁻¹ and MA rad⁻¹ in the north and south, respectively, in general agreement with previous results. Taking the currents and effective Pedersen conductance together, we find that the average ME intensity and plasma flow speed in the middle magnetosphere (10–30 R_J) are broadly consistent with one another under MI coupling theory. We find evidence for peaks in the distribution of near dawn, then again near 12 and 14 hr magnetic local time (MLT). This variation in Pedersen conductance with MLT may indicate the importance of conductance in modulating MLT- and local-time-asymmetries in the ME, including the apparent subcorotation of some auroral features within the ME.

中文翻译：

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木星主发射极光附近佩德森电导的变化：哈勃太空望远镜和伽利略测量的比较

我们提出了对木星主要发射（ME）的第一次大规模统计调查，将极光特性从电离层位置映射到磁层的赤道平面，在那里将它们直接与现场航天器测量结果进行比较。我们使用磁层-电离层 (MI) 耦合理论，根据哈勃太空望远镜测量的极光亮度和伽利略航天器现场测量的等离子体流速来计算电流。电离层有效佩德森电导在此比较中仍然是一个自由参数。我们根据组合数据集计算 Pedersen 电导，发现其范围为mho 总体平均值为mho 在北部和姆霍在南部。仅考虑 HST 导出的每方位角弧度的场对准电流，我们发现值MA rad ⁻¹和北部和南部分别为MA rad ^{-1 ，与之前的结果基本一致。}将电流和有效 Pedersen 电导放在一起，我们发现在 MI 耦合理论下，中磁层 (10–30 R _J ) 的平均 ME 强度和等离子体流速大致一致。我们找到了分布峰值的证据黎明时分，然后又在磁当地时间 (MLT) 12 点和 14 点附近。Pedersen 电导随 MLT 的变化可能表明电导在调节 ME 中 MLT 和局地时间不对称性方面的重要性，包括 ME 内某些极光特征的明显次共转。