Dear Collaborators,
NOAA 12817 was the source of numerous B-class flares as well as two C-class flares (C1.9 and C1.5) in the past 24 hours. 12817 has been designated as a beta/D-type region, with increasing its sunspot area and number of spots. Today the target will switch to this region that continues to show flux emergence. Further B-class activities are expected and additional low C-class events are very likely when 12817 rotates to the west limb.
The position of NOAA 12817 on April 21 at 03:30 UT is:
N18W64 (817", 329")
See http://www.SolarMonitor.org for images and http://solar.physics.montana.edu/max_millennium/ops/observing.shtml for a description of the current Max Millennium Observing Plan.
Regards,
Ying Li (Purple Mountain Observatory)