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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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  • Sunspot070110

    07/02/2010 | The K7RA Solar Update

    Most stations reported not-so-great conditions for ARRL Field Day last weekend, but there were sporadic-E openings on 6 and 10 meters. Geomagnetic conditions were a bit rough, with the Planetary A index in double digits for both days, June 26-27. Conditio
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  • Sunspot062410

    06/25/2010 | The K7RA Solar Update

    Sunspot numbers were lower for the past week, compared to the previous period. The average daily sunspot numbers fell nearly 11 points to 16.1. Sunspot numbers for June 17-23 were 14, 16, 28, 13, 14, 14 and 14, with a mean of 16.1. The 10.7 cm flux was 70
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  • Sunspot060310

    06/04/2010 | The K7RA Solar Update

    The average daily sunspot numbers were up nine points to 25.3 for this week, compared to the May 20-26 period; the average daily planetary A index rose nearly 10 points to 14.3, and this rise in geomagnetic instability came with the increase in solar acti
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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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  • Sunspot043010

    04/30/2010 | The K7RA Solar Update

    Our Sun has again become very quiet. We saw 13 days with no sunspots, April 15-27, then new sunspot group 1063 appeared April 28, and on April 29 it was gone again. Although the sunspot number for April 29 is 0, early on April 30 I can still see group 106
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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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