The heliosphere is the region around the Sun that is filled with the solar wind, a stream of charged particles. Voyager 1 and 2, the space probes launched by NASA, crossed the heliopause, the boundary of the heliosphere, at a distance of 122 AU and 121 AU from the Sun, respectively. These events led to a revision of the expected thickness of the heliosheath, the region between the heliospheric termination shock and the heliopause, in the direction of Voyager 1. To better understand these observations, researchers V.V. Izmodenov and D.B. Alexashov developed a 3D kinetic-MHD model of the solar wind interaction with the local interstellar medium that takes into account the effect of thermal electron conduction. The results showed a strong effect of thermal conduction on the plasma flow in the inner heliosheath, which led to a depletion of plasma temperature and pressure towards the heliopause. The model also showed an increase in plasma temperature in the supersonic solar wind upstream of the termination shock. Overall, the study provides a more detailed understanding of the global structure of the heliosphere.
reference: https://doi.org/10.48550/arXiv.2303.05547