June 11 2012 Sunspot AR1504 Crackling w Impulsive M-Class Solar Flare HD

 
SHAPE-SHIFTING SUNSPOT: As it pops and crackles with low level solar flares, sunspot AR1504 is rapidly evolving. During the past 24 hours the active region has shape-shifted from an irregular dumbbell into a dark ring of magnetism wide enough to circumscribe a half-dozen planet Earths:
NOAA forecasters estimate a 55% chance of M-class solar flares today as the sunspot's magnetic field shifts and destabilizes. Eruptions later this week could be geoeffective as the sunspot turns to face Earth.