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  • sunspot082710

    08/27/2010 | The K7RA Solar Update

    This week, we saw three days -- August 21-23 -- with no sunspots, and the average daily sunspot numbers for the week -- August 19-25 -- declined over 28 points to 8, compared to the previous week. The average daily solar flux was down more than 8 points t
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  • Sunspot081310

    08/13/2010 | The K7RA Solar Update

    Sunspot numbers and solar flux increased this week, with the average daily sunspot numbers up more than 32 points to 53, and the average daily 10.7-cm solar flux up more than 3 points to 84.5. These are the numbers from last Thursday through this Wednesda
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  • Sunspot080610

    08/06/2010 | The K7RA Solar Update

    Sunspot numbers and solar flux declined this week, with the average daily sunspot numbers down more than 15 points to 20.3, and the average daily solar flux down nearly 4 points to 81.4. These are the numbers from last Thursday through this Wednesday, Jul
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  • Sunspot061710

    06/18/2010 | The K7RA Solar Update

    The average daily sunspot numbers were up 2.5 points from last week, despite the fact that there were no sunspots at all this week on June 15-16. A new sunspot group 1082 emerged yesterday, June 17, and yielded a daily sunspot number of 14. A nice thing a
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  • Sunspot050610

    05/07/2010 | The K7RA Solar Update

    Sunspots made a strong return this week -- and so did geomagnetic activity. The average daily solar flux increased 4.2 points to 79.6; on Wednesday, May 5, the daily sunspot number reached 77, the highest in nearly four years. The sunspot number hasn’t be
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  • Sunspot040810

    04/09/2010 | The K7RA Solar Update

    A strong geomagnetic storm on Monday and Tuesday -- April 5-6 -- was the biggest since 2006, at least in terms of high planetary A index. On those days, the mid-latitude A index was 28 and 22 and the planetary A index was 49 and 46. This was caused by a m
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  • 10/23/2009 | The K7RA Solar Update

    A tiny Solar Cycle 24 sunspot group -- numbered 1028 -- emerged briefly on Tuesday, October 20, and then was gone. This is another brief phantom sunspot, teasing us with hints of the expected increase in activity that never seems to manifest. Of course, t
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  • 07/17/2009 | The K7RA Solar Update

    We saw a nice run of eight days with a large sunspot, but none have emerged in the six days since. Unlike other recent spots, this one did not appear just for one or two days and then vanish. Sunspot numbers for July 9-15 were 15, 13, 0, 0, 0, 0 and 0 wit
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