The Solar Astronomy Laboratory of the Space Research Institute (IKI) and the Institute of Solar-Terrestrial Physics (ISZF) published a video of a solar ejection the day before, commenting on the nature of the so-called dark cavity.
In a nutshell, these observations correspond to modern ideas about emissions (the so-called flux rope model), according to which a round (in cross-section), and in fact cylindrical, magnetic structure should form in the center of the emission, as shown in this figure. Here, perhaps, it looks even clearer.
In the center of the cavity there is either a protuberance flying away from the Sun, or simply a strong current flows, around which, in fact, the magnetic lines are twisted, the scientists noted.
The main task of this structure is to ensure the separation of magnetic lines from the Sun, because without this, the plasma simply will not be able to fly away. It is not often possible to see this theoretical cavern in a real emission, and the observations are really rare. There is no doubt that the video will be torn apart into several scientific articles.
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