Far tail plasma boundaries at Venus from the Solar Orbiter, Parker Solar Probe and BepiColombo flybys

We present findings from the several flybys made by the Solar Orbiter, BepiColombo, and Parker Solar Probe missions, aimed at investigating the structure and dynamics of Venus' magnetotail. Our study focuses on the interplay between Venus' plasma environment and the solar wind, which shapes the induced magnetosphere. By analyzing magnetic field and plasma density data, we determine the spatial reach and behavior of Venus' magnetotail, and in particulat focus on the time and location of plasma boundary crossings. Notably, we observe significant differences in boundary crossing positions and characteristics across different encounters, underscoring the dynamic nature of Venus' magnetotail. Key observations include identifying boundary crossings such as the bow shock, observed down to approximately 60 Venus radii (6052 km) downstream, and the induced magnetospheric boundary roughly at 100 Venus radii downstream. This insight sheds light on the extent of the induced magnetosphere and allows for the refinement of existing boundary models. Previous models, based on data from Venus Express, were limited to within approximately five Venus radii of the planet; our analysis suggests modifications to better accommodate far-downstream encounters. Additionally, our analysis reveals the influence of solar wind conditions on magnetotail behavior: during Solar Orbiter's third encounter, characterized by extreme solar wind conditions, significant fluctuations in magnetosheath plasma density and magnetic field properties were observed. However, contrary to expectations perhaps, the increased dynamic pressure did not compress the magnetotail; instead, increased EUV flux during this period is suggested to have led to its expansion.