Solar activity: growing threat of flares

GROWING THREAT OF FLARES: What a difference a weekend makes. Since Friday, sunspot AR1363 has nearly tripled in area and it has developed a delta-class magnetic field that harbors energy for X-class solar flares. This 48-hour movie from NASA's Solar Dynamic Observatory shows the changes on Dec. 3-4:

Despite its growing potential for explosions, the sunspot remains mostly quiet producing no flares stronger than C-class. Is this the quiet before the storm--or just plain quiet? Stay tuned

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