Magnetohydrodynamical Phenomena in the Solar Corona as revealed by Yohkoh

Extract

In the talk, some of the new findings about the magnetodynamical phenomen a in the inner corona obtained by the satellite Yohkoh were reviewed. Here we give a very brief summary of it. (The long list of references has been omitted due to the limitation of space here.)

One of the most remarkable findings by Yohkoh is that the corona is quite a dynamic entity. Such a dynamicity was recognized in its full form by the wide-dynamic range, high cadence imaging from Yohkoh-Soft X-ray Telescope (SXT) with the use of the video-movie presentation. It turned out that the background corona formed quite a dynamic system with the active regions (Uchida 1992, Tsuneta and Lemen 1992), and many examples of interesting dynamic interplay between them were found. It may well be said that the corona is not an “atmosphere” of the usual sense, but is an entity highly electromagnetic in character.