Large Sunspot Group AR 9393 24-03-01 to 2-04-01 
The largest sunspot group of the past ten years crosses the surface of the Sun. The group was designated Active Region 9393 as it was the 9393rd region identified since counting officially began in 1973. The number of active regions on the Sun was high because the Sun was reaching the maximum of its 11-year cycle of magnetic activity.
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Credit: MDI, SOHO, ESA, NASA  

The largest sunspot group of the past ten years crosses the surface of the Sun. The group was designated Active Region 9393 as it was the 9393rd region identified since counting officially began in 1973. The number of active regions on the Sun was high recently because the Sun was reaching the maximum of its 11-year cycle of magnetic activity. The above time-lapse sequence shows AR 9393 as it evolved from 27 March to 2 April 2001, to become over 10 times larger than our Earth. Just after the end of the movie, on 2 April, AR 9393 unleashed the largest solar flare of the last 25 years. Luckily, the flare was not pointed toward the Earth, or flare particles might have damaged satellites or even caused local electrical blackouts.  
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