The largest sunspot AR2192, since November 1990, produced 10 significant solar flare while traversing the Earth-side of the sun in ten days beginning from October 19, 2014.
There were six X-class and four above M5-class. The region was so large it could be seen without a telescope for those looking at the sun with eclipse glasses.
Such active regions are measured in millionths of a solar hemisphere, where 1 micro-hemisphere, or MH, is about 600,000 square miles. This region topped out at 2,750 MH, making it the 33rd largest region out of approximately 32,000 active regions that have been tracked and measured since 1874.
AR 12192 rotated onto the far side of the sun on Oct. 30, 2014, however as it evolves, a new version of it rotating back into view in two weeks might be seen.
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