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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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  • Sunspot072910

    07/30/2010 | The K7RA Solar Update

    Sunspot activity increased again this week, but on Tuesday and Wednesday -- July 27-28 -- a stiff solar wind increased Earth’s geomagnetic activity, which is a negative for HF propagation. Sunspot numbers for July 22-28 were 39, 45, 41, 39, 39, 15 and 31,
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  • Sunspot072210

    07/23/2010 | The K7RA Solar Update

    Sunspot activity increased recently, although it is foolish to call this a trend, since solar activity has great variability. Sunspot group 1087 was visible for 13 days over July 9-21. In millionths of a solar hemisphere, its size was 30, 100, 120, 130, 7
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  • Sunspot051410

    05/14/2010 | The K7RA Solar Update

    This lack of sunspots is bothersome. Thursday -- May 13 -- is the fifth day in a row with no spots, and there is no sign of any change. The solar flux has been declining and is now below 70. The predicted solar flux for May 14-19 is 70, then 74 on May 20,
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  • sunspot040110

    04/02/2010 | The K7RA Solar Update

    Even though this bulletin may arrive a little early (due to the Good Friday holiday on April 2), jokesters are still too late for sneaking any First of April pranks into this bulletin. No matter when you read it, this bulletin is dated April 2 for good re
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  • sunspot012110

    01/22/2010 | The K7RA Solar Update

    A steady stream of sunspot activity continues to dot the Sun. We had just one day with a daily sunspot number of 0 this week -- January 19 (Tuesday) when sunspot group 1040 moved over the horizon.
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  • sunspot010810

    01/08/2010 | The K7RA Solar Update

    Recent sunspot activity is increasing, and the numbers bear this out. The average daily sunspot number for 2009 was 5 and the average for 2008 was 4.7.
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  • sunspot122409

    12/24/2009 | The K7RA Solar Update

    Many of us are nearly giddy with joy over the recent steady increase in sunspot activity that seems long overdue. Average daily sunspot numbers rose more than 10 points this week compared to last -- from 21.1 to 31.4! The monthly average daily sunspot num
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