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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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  • Sunspot041510

    04/16/2010 | The K7RA Solar Update

    Weakened sunspots faded this week, and we were buffeted with more geomagnetic instability, but without the dramatic geomagnetic storms of the previous week. The average daily sunspot numbers fell more than 20 points to 12.1, and the average solar flux dro
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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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  • sunspot012910

    01/29/2010 | The K7RA Solar Update

    Recent sunspot activity is increasing, and the numbers bear this out.
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  • 01/02/2009 | The K7RA Solar Update

    2008 was a year of very low solar activity. More than 40 percent of this year's propagation bulletins reported zero sunspots for their respective weeks. The average daily sunspot number for the year was 4.7; in 2007, it was 12.8. The yearly averages of da
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  • 04/25/2008 | The K7RA Solar Update

    This week we had a couple of brief sunspot appearances -- 991 and 992 -- but they were both from Solar Cycle 23 and their emergence was fleeting. On Wednesday, April 23, the planetary A index rose to 32 due to a solar wind and south-pointing Interplanetar
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