Illuminating the Darkness: Unraveling Theta Aurora Dynamics under Northward IMF Conditions

Theta auroras, forming a distinctive arc across the polar cap in a shape reminiscent of the Greek letter theta, emerge as an enigmatic phenomenon under northward interplanetary magnetic field (IMF) conditions. The appearance of theta auroras signals a complex interplay of solar wind energy transfer into the magnetosphere, contrary to the expectation of low magnetospheric activity under such conditions. We explore the dynamics of theta aurora formation by employing the Space Weather Modeling Framework (SWMF) to simulate these events. Our analysis indicates that the theta aurora is associated with magnetic topologies within a highly twisted magnetotail as well as multiple reconnection regions along the magnetotail flank. Though the theta aurora may appear as a single structure in the ionosphere, we suggest that its precipitation sources can be widely spread in the magnetosphere. Our findings underscore the complexity of the magnetotail during periods of northward IMF and highlight the importance of a combination of comprehensive auroral observations and modeling for understanding the multifaceted responses of the magnetosphere to solar wind drivers. Future work will continue to investigate theta aurora formation mechanisms and the role they play during northward IMF-driven solar wind energy transfer into the magnetosphere.