Jovian UV Aurora's Response to the Solar Wind: Hisaki EXCEED and Juno Observations
Jovian UV Aurora's Response to the Solar Wind: Hisaki EXCEED and Juno Observations
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木星紫外线极光对太阳风的响应：Hisaki EXCEED 和朱诺观测
DOI：
10.1029/2019ja026997
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Fujimoto M.
中科院分区：
文献类型：
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作者：
Kita H.;Kimura T.;Tao C.;Tsuchiya F.;Murakami G.;Yamazaki A.;Yoshioka K.;Ebert R.W.;Wilson R.J.;Allegrini F.;Clark G.;Connerney J. E. P.;Gladstone G. R.;Yoshikawa I.;Fujimoto M.
我们总结了2016年朱诺接近木星期间木星紫外线(UV)极光对太阳风动态气压变化的响应。由于上游现场太阳风测量的稀少，木星极光对外部驱动的响应时间迄今尚不清楚。将朱诺太阳风观测与Hisaki Extra(极端紫外线光谱仪)和JUNO UV光谱仪获得的连续紫外线极光数据结合起来，对三次主要激波到达的紫外线极光变亮的响应显示出10-15小时的时间滞后。这些时间滞后比太阳风对激波进行弹道传播所需的时间要长。除了这个谜题，尽管当动态气压增加到~0.03nPa时，紫外极光的功率被观察到了增强，但当动态气压升高到>；0.1npa时，并没有观察到与之相关的亮化。这意味着需要考虑到内部磁层方面，以充分解决这个问题。
We summarize Jupiter's ultraviolet (UV) auroral response to solar wind dynamic pressure variations during Juno's approach to Jupiter in 2016. The response time of Jupiter's aurora to external drivers has thus far been unknown owing to a sparsity of upstream in situ solar wind measurements. Combining the Juno solar wind observations with continuous UV aurora data obtained by Hisaki EXCEED (Extreme Ultraviolet Spectroscope for Exospheric Dynamics) and Juno UV spectrograph, the UV aurora brightenings in response to three major shock arrivals showed time lags of 10–15 hr. These time lags are longer than the time required for ballistic propagation of the shocks by the solar wind. In addition to that puzzle, while an enhancement in the UV auroral power was observed with an increase in dynamic pressure to ~0.03 nPa, no associated brightening was observed with a dynamic pressure elevation of >0.1 nPa. These imply that internal magnetospheric aspects need to be taken into consideration to fully resolve the issue.