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arXiv · 2207.12175

Overview of the remote sensing observations from PSP solar encounter 10 with perihelion at 13.3 Rsun

Abstract

The closest perihelion pass of Parker Solar Probe (PSP), so far, occurred between 16 and 26 of November 2021 and reached ~13.29 Rsun from Sun center. This pass resulted in very unique observations of the solar corona by the Wide-field Instrument for Solar PRobe (WISPR). WISPR observed at least ten CMEs, some of which were so close that the structures appear distorted. All of the CMEs appeared to have a magnetic flux rope (MFR) structure and most were oriented such that the view was along the axis orientation, revealing very complex interiors. Two CMEs had a small MFR develop in the interior, with a bright circular boundary surrounding a very dark interior. Trailing the larger CMEs were substantial outflows of small blobs and flux-rope like structures within striated ribbons, lasting for many hours. When the heliophysics plasma sheet (HPS) was inclined, as it was during the days around perihelion on November 21, 2021, the outflow was over a very wide latitude range. One CME was overtaken by a faster one, with a resultant compression of the rear of the leading CME and an unusual expansion in the trailing CME. The small Thomson Surface creates brightness variations of structures as they pass through the field of view. In addition to this dynamic activity, a brightness band from excess dust along the orbit of asteroid/comet 3200 Phaethon is also seen for several days.

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Russell A. Howard, Guillermo Stenborg, Angelos Vourlidas, Brendan M. Gallagher, Mark G. Linton, Phillip Hess, Nathan B. Rich, Paulett C. Liewer. 2022-07-25. Overview of the remote sensing observations from PSP solar encounter 10 with perihelion at 13.3 Rsun. https://doi.org/10.3847/1538-4357%2Fac7ff5

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