Abstract
Magnetosheath jets represent localized enhancements in dynamic pressure
observed within the magnetosheath. These energetic entities, carrying
excess energy and momentum, can impact the magnetopause and disrupt the
magnetosphere. Therefore, they play a vital role in coupling the solar
wind and terrestrial magnetosphere. However, our understanding of the
morphology and formation of these complex, transient events remains
incomplete over two decades after their initial observation. Previous
studies have relied on oversimplified assumptions, considering jets as
elongated cylinders with dimensions ranging from 0.1 RE to 5.0 RE (Earth
radii). In this study, we present simulation results obtained from
Amitis, a high-performance hybrid-kinetic plasma framework (particle
ions and fluid electrons) running in parallel on Graphics Processing
Units (GPUs) for fast and more environmentally friendly computation
compared to CPU-based models. Considering realistic scales, we present
the first global, three-dimensional (3D in both configuration and
velocity spaces) hybrid-kinetic simulation results of the interaction
between solar wind plasma and Earth. Our high-resolution kinetic
simulations reveal the 3D structure of magnetosheath jets, showing that
jets are far from being simple cylinders. Instead, they exhibit
intricate and highly interconnected structures with dynamic 3D
characteristics. As they move through the magnetosheath, they wrinkle,
fold, merge, and split in complex ways before a subset reaches the
magnetopause.