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The First Active Region of the New Solar Cycle?

Image name: first_spots_of_new_cycle.png (click image to enlarge)
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Date submitted: 02-Sep-1995

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

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