Dayside transient phenomena and their effects on planetary magnetospheres

Upstream from the bow shock, some incident solar wind particles can be reflected and under specific geometrical conditions, travel upstream along the magnetic field lines, interact with the solar wind and cause a variety of instabilities and waves before getting carried back to the shock. This complex interaction gives rise to the foreshock environment, where several phenomena take place. These include whistler and ULF waves, hot flow anomalies (HFAs), spontaneous hot flow anomalies (SHFAs), foreshock cavities, foreshock bubbles, shocklets, and short-large amplitude magnetic structures (SLAMS). Such foreshock structures appear to govern much of the dynamics upstream of the planetary bow shocks, while modulating the downstream magnetosheath region. They may cause high-speed plasma jets and plasmoids downstream of the shock, or even get directly transmitted through the bow shock. Understanding the coupling between these processes and revealing their effects with respect to the magnetosphere is crucial for the accurate determination of a planetary geospace environment and for quantifying possible space weather effects. On a more fundamental level, such structures and their relation can be connected to phenomena such as magnetic reconnection, particle acceleration and the magnetosphere-ionosphere coupling. Contributions to this session can include theoretical works, computer simulations, numerical modeling, machine learning applications and observational research. We particularly encourage presentations using data from Terrestrial missions of MMS, THEMIS, and Cluster missions in conjunction with other missions such as Arase (ERG), Van Allen Probes (VAPs) and ground magnetometers. Of particular interest are works that study transient phenomena close to the bow shock of other planetary environments such as Mercury, Venus, and Mars using simulations or observational measurements.