MAGNETIC FROTH: Sunspot AR1598 has quieted down since unleashing an X1-class solar flare on Oct. 23rd. It might be the calm before the storm. The sunspot is still large and apparently potent, as shown in this image captured by amateur astronomer Sergio Castillo of Inglewood,California:

Castillo used a telescope capped with a “Calcium K” filter tuned to the light of ionized calcium atoms in the sun’s lower atmosphere. Calcium K filters highlight the bright magnetic froth that sometimes forms around a sunspot’s dark core. AR1598 is very frothy indeed.

Magnetic froth does not necessarily herald an explosion, but it does guarantee a photogenic sunspot

fr/spaceweather.com