AGS-PRF: To what Extent are Jupiter's Magnetosphere and Aurora Influenced by the Solar Wind?

AGS-PRF：木星磁层和极光在多大程度上受到太阳风的影响？

• 批准号: 1524651
• 负责人: Marissa Vogt
• 金额: $ 8.6万
• 依托单位: Vogt Marissa F
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1524651&HistoricalAwards=false
• 关键词: AGS; PRF; what; Extent; Jupiter

The solar wind of charged particles and magnetic fields blowing outward from the Sun interacts with Jupiter's magnetosphere, the region of space controlled by its magnetic field. But does this interaction make a significant difference to the Jovian magnetospheric dynamics as it does at Earth? Most believe that the effects of any interaction with the solar wind are completely overwhelmed by the effects of the rapid rotation of Jupiter's strong magnetic field and the extended torus of heavy ions created by Io's volcanoes. This question continues to be an area of active research and debate due in part to the lack of available solar wind measurements near Jupiter's orbit. The study will use a model that propagates solar wind conditions measured near Earth out to Jupiter in order to estimate solar wind conditions there. The work will examine observations of magnetic fields and particles within Jupiter's magnetosphere by the Galileo spacecraft, and images of Jupiter's aurora taken by the Hubble Space Telescope, to determine whether changes in these data may be statistically associated with changes in the modeled solar wind conditions. The results of this work will add to our knowledge of how planetary magnetospheres work, putting our understanding of the Earth's magnetosphere into a broader context, and informing the study of star-exoplanet interactions. This grant supports the training of a female postdoctoral student. Results from the research and other recent advances in space plasma physics will be presented to the public during the Boston University Astronomy Department's weekly public open night at the campus observatory while groups are waiting to use the telescopes. Additionally, the proposer will mentor graduate students at Boston University through the Graduate Women in Science and Engineering program. Previous attempts have been made to model solar wind conditions at Jupiter based on solar wind conditions near Earth but the success of this technique has so far been limited by the large uncertainties in the arrival times of solar wind disturbances. These uncertainties in turn make linking dynamical responses of Jupiter's magnetosphere to particular solar wind disturbances problematic. The innovation in this proposal is to use the observed compression of Jupiter's magnetic field in response to the dynamic pressure changes in the solar wind to refine the arrival time of disturbances in the solar wind and minimize uncertainties in timing. The statistical correlation (or lack thereof) between the arrival of solar wind disturbances and changes in Jupiter's magnetosphere and aurora will test the importance of solar wind interactions. Of particular importance, it will address whether quasi-periodic behavior observed in Jupiter's magnetosphere might be controlled by the solar wind. This study will also determine how Jupiter's main auroral emissions respond to changing solar wind conditions, and compare findings to theories and models.

从太阳向外吹出的带电粒子和磁场的太阳风与木星的磁层相互作用，木星的磁层是由其磁场控制的空间区域。但是，这种相互作用对木星磁层动力学的影响是否与地球上的情况有显著差异？大多数人认为，与太阳风的任何相互作用的影响都完全被木星强磁场的快速旋转和木卫一火山产生的重离子扩展环面的影响所压倒。这个问题仍然是一个活跃的研究和辩论领域，部分原因是缺乏木星轨道附近的太阳风测量。该研究将使用一个模型，将在地球附近测量的太阳风条件传播到木星，以估计那里的太阳风条件。这项工作将检查伽利略航天器对木星磁层内磁场和粒子的观测，以及哈勃太空望远镜拍摄的木星极光图像，以确定这些数据的变化是否与模拟太阳风条件的变化有统计学关联。这项工作的结果将增加我们对行星磁层如何工作的了解，将我们对地球磁层的理解置于更广泛的背景下，并为恒星-系外行星相互作用的研究提供信息。这笔赠款用于资助一名女博士后的培训。研究结果和空间等离子体物理学的其他最新进展将在波士顿大学天文学系每周在校园天文台举行的公众开放之夜期间向公众展示，而团体正在等待使用望远镜。此外，提议者将通过研究生妇女在科学和工程计划指导研究生在波士顿大学。以前的尝试是根据地球附近的太阳风条件来模拟木星的太阳风条件，但到目前为止，这种技术的成功受到太阳风扰动到达时间的巨大不确定性的限制。 这些不确定性反过来又使得将木星磁层的动态响应与特定的太阳风扰动联系起来成为问题。 该提案的创新之处在于，利用观测到的木星磁场对太阳风动态压力变化的压缩，来精确太阳风扰动的到达时间，并将时间上的不确定性降到最低。太阳风扰动的到来与木星磁层和极光的变化之间的统计相关性（或缺乏相关性）将测试太阳风相互作用的重要性。 特别重要的是，它将解决在木星磁层中观察到的准周期行为是否可能受到太阳风的控制。这项研究还将确定木星的主要极光排放如何对不断变化的太阳风条件作出反应，并将研究结果与理论和模型进行比较。