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    02/15/2011 | Sunspot 1158 Produces Largest Flare of Solar Cycle 24; CME Headed Toward Earth

    Over the past few days, there has been a lot of activity on the Sun. On Sunday, February 13 at 1738 UTC, sunspot 1158 unleashed an M6.6-level blast and on Tuesday, February 15, the same sunspot unleashed an X-class flare, the strongest solar flare in more
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    02/11/2011 | The K7RA Solar Update

    Seven different sunspot groups were visible over the past week. The high sunspot number in the past seven days was 71 on Tuesday, and the average daily sunspot number more than doubled, rising more than 24 points to 44.3. The average daily solar flux was
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    02/04/2011 | The K7RA Solar Update

    The past week had one 0 sunspot day -- Thursday, January 27. Even though the activity came right back, the average daily sunspot number for the week fell more than 12 points to 20.1, and the average daily solar flux declined 2.7 points to 80.8. After the
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    01/21/2011 | The K7RA Solar Update

    The average daily sunspot numbers dropped from 50 (on the reporting week ending January 5) to 38 on January 6-12, and now 21.3 on January 13-19. Sunspot numbers for January 13-19 were 14, 11, 11, 15, 36, 34 and 28, with a mean of 21.3. The 10.7 cm flux wa
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    12/31/2010 | The K7RA Solar Update

    There were no sunspots for a full week, December 18-24. Christmas Day saw a return to sunspot activity, so the last two of those spotless days were in the Thursday through Wednesday reporting period in this bulletin, December 23-29. The average daily suns
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    12/10/2010 | The K7RA Solar Update

    The average daily sunspot numbers for the week were up more than nine points to 35, and average solar flux rose more than six points to 87.3. These differences compare the dates of December 2-8 with the previous seven days. The average planetary A index d
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    10/01/2010 | The K7RA Solar Update

    HF radio conditions were good over this past week, with the average daily sunspot numbers up more than 5 points to 45.3, and the average solar flux rising 1.5 points to 84.4. On Wednesday, September 29, the solar flux was 90.7; the last time flux values w
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