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The First Active Region of the New Solar Cycle? The announcement by BBSO that the first spot group of the new cycle had been detected on August 12, 1995, surprised many people. These images show the soft X-ray appearance of the region several days later (19 August 1995 14:31 UT). The left panel shows a Yohkoh/SXT full-sun image and the middle panel a blow-up with an arrow pointing to the new region. Grid marks are every 10 heliographic degrees, and the thick line shows the location of the Sun's equator. The panel on the right shows a Kitt Peak National Observatory magnetogram from 20 August, 15:55 UT, about a day later. The polarities of the northern active region and the new southern active region are the same. We see nothing particularly unusual about this new-cycle (?) active region in soft x-rays, but would any differences be expected?
The initial soft x-ray emission from this region appeared rather suddenly, between SXT images taken at 13:29 and 14:26 UT, 11 August, while the region was at about E80. Although SXT could see the new region quite early, we note that there is no easy way to measure the magnetic polarity with X-radiation!
K. Reardon and H. Hudson, 2 September 1995