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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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  • 02/13/2009 | The K7RA Solar Update

    Sunspots returned this week, or rather, one did, but it is an old Solar Cycle 23 spot. Sunspot 1012 has been visible the last couple of days, February 11-12. It is down near the Sun's equator, typical for spots from a previous cycle. It's nice to have a s
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  • 02/06/2009 | The K7RA Solar Update

    We still have had no hint of sunspots or sunspots to come, though there was some geomagnetic activity on February 4 from a possible coronal mass ejection, raising the planetary A index to 16 that day. Sunspot numbers for January 29-February 4 were 0, 0, 0
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