Since the launch on 2018 August 12, the Parker Solar Probe (PSP) has completed its first five orbits around the Sun, having reached down to ~28 solar radii at perihelion 5 on 2020 June 7. More recently, the Solar Orbiter (SolO) made its first close approach to the Sun at 0.52 AU on 2020 June 15, nearly 4 months after the launch. Using a 3D heliospheric MHD model coupled with the Wang-Sheeley-Arge (WSA) coronal model using the Air Force Data Assimilative Photospheric flux Transport (ADAPT) magnetic maps as input, we simulate the time-varying inner heliosphere, including the trajectories of PSP and SolO, during the current solar minimum period between 2018 and 2020. Above the ADAPT-WSA model outer boundary at 21.5 solar radii, we solve the Reynolds averaged MHD equations with turbulence and pickup ions taken into account and compare the simulation results with the PSP solar wind and magnetic field data, with particular emphasis on the large-scale solar wind structure and magnetic connectivity during each solar encounter.
Evolution of Solar Wind Turbulence from 0.1 to 1 au during the First Parker Solar Probe–Solar Orbiter Radial Alignment
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