EAGER: Long-Term Solar Wind Trends and the Implications for Current and Future Solar Activity

首席调查员将对太阳风的长期趋势进行长期评估。这将包括利用替代数据(特别是安静时间的日侧磁强计观测)，以(1)确定太阳风动态压力在整个20世纪是否一直随着星际磁场的增加而增加；(2)探索新发现的太阳风氦丰度与星际磁场之间的关系；(3)在氦丰度骤降至远低于过去50年正常水平的值的情况下，调查这种关系的变化。这项研究可能会为建立一个全面的现象学框架指明道路，该框架可以根据太阳周期的演变来理解太阳风的变化，甚至可能提供证据，证明长达一个多世纪的大太阳活动已经结束。这一研究方向也可能为更广泛的太阳物理学提供重要线索，因为它试图提高我们对太阳的理解。该项目将支持培养一名深度参与研究的本科生。此外，更好地了解太阳活动，以及利用太阳风趋势来预测太阳活动，将使我们的文明能够改进空间天气预报，从而减轻对我们所依赖的、易受空间天气影响的在轨和地面技术的负面影响。

The Principal Investigator will perform an extended evaluation of long-term solar wind trends. This will include using proxy data (specifically, quiet-time dayside magnetometer observations) to (1) determine whether solar wind dynamic pressure has been increasing throughout the 20th century along with the interplanetary magnetic field (IMF); (2) explore the newly discovered relationship between the solar wind helium abundance and the IMF; and (3) investigate the changes in that relationship as the helium abundance has plummeted to values far below the normal level for the last 50 years. This research might point the way to a comprehensive phenomenological framework that provides an understanding of solar wind changes in terms of the evolution of the solar cycle, and perhaps even provide evidence that the more than century-long Grand Solar Maximum is at an end. This line of research may also provide important clues for solar physics more broadly, as it attempts to improve our understanding of the Sun.The project will support the training of an undergraduate student who will be deeply involved in the research. In addition, a better understanding of solar activity, as well as the use of solar wind trends to predict solar activity, will allow our civilization to improve space weather forecasting and thereby mitigate the negative effects on the on-orbit and ground-based technology upon which we depend and which is vulnerable to space weather effects.