The ionosphere of Jupiter in the Juno era

美国宇航局朱诺号航天器自2016年以来一直在木星轨道上，在53天长的极地轨道上运行。这提供了全新的、戏剧性的地球视角，与我们在地球上看到的截然不同。轨道器上的近红外仪器(JIRAM-木星红外极光映射器)提供了令人震惊的电离层数据，电离层是高层大气的带电粒子成分。电离层是一个非常重要的区域，因为它可以“感觉”到磁场，并且在那里是一个动量和能量在大气层和磁层之间交换的区域。木星上令人惊叹的明亮和多变的极光显示提供了一种机制来加热两极的高层大气，但这种能量是如何重新分配到较低纬度的？我们对极光区域以外的电离层的了解非常有限，朱诺JIRAM提供了一个窗口，通过它我们可以开始了解这一区域。电离层中的主要离子是分子离子H3+，通过使用莱斯特开发的模型对其观测光谱进行拟合，我们可以确定行星上任何特定点的温度和离子密度，每个连续的轨道都提供了这种变化随时间变化的视图。这个项目将研究能量如何在木星的上层大气中重新分配，以及由湍流的下层大气产生的重力波加热在全球范围内有多重要。我们还将有机会利用夏威夷的美国宇航局红外望远镜设施领导朱诺支助观测，从中我们可以确定磁层对电离层和大气层施加的作用力，这是对朱诺综合信息库获取的高空间分辨率数据的高度补充的数据产品。

"The NASA Juno spacecraft has been in orbit at Jupiter since 2016 in 53 day long polar orbit. This provides completely new and dramatic views of the planet, very different from the ones we get from here at Earth. The near-infrared instrument on the orbiter (JIRAM - the Jovian Infrared Auroral Mapper) provides stunning data of ionosphere, the charged particle component of the upper atmosphere. The ionosphere is a very important region since it can 'feel' the magnetic field, and is there for a region where momentum and energy is exchanged between the atmosphere and the magnetosphere. The stunningly bright and variable auroral displays at Jupiter provides a mechanism to heat the upper atmosphere at the poles, but how is this energy re-distributed towards lower latitudes? Our understanding of the ionosphere away from the auroral region is very limited, and Juno JIRAM provides a window through which we can begin to understand this region. A dominant ion in the ionosphere is the molecular ion H3+, and by fitting its observed spectrum using the model developed at Leicester we can determine the temperature and ion density of any particular point on the planet, with each successive orbit providing a view of how this changes over time. This project will investigate how energy is re-distributed in the upper atmosphere of Jupiter, and how important the heating by gravity waves, generated by the turbulent lower atmosphere, are on a global scale. Will also have the opportunity to lead Juno support observations using the NASA Infrared Telescope Facility in Hawaii, from which we can determine the amount of forcing that the magnetosphere exerts on the ionosphere and atmosphere, a highly complementary data product to the high spatial resolution data taken by Juno JIRAM.