Oct. 14, 2003, dawned with a virtually spotless sun. It turned out to be the calm before the storm. During the next few days, the number and size of sunspots increased. On Oct. 18, a massive solar flare spewed from a newly visible sunspot near the eastern edge of the sun. The sun's rotation carried this Jupiter-size zone of intense magnetic activity across the solar face and, on Oct. 23, another hyperactive spot of similar size spun into view. A third blemish popped up on the sun's left cheek on Oct. 27, tripled in size by the next day, and then quickly doubled. At their largest, these three dark pocks and their smaller satellite blotches covered enough of the sun's surface to cause a dip in solar radiation measurable by Earth-orbiting satellites.
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