ARRL

Search for Amateur Radio News

  • Sunspot081910

    08/20/2010 | The K7RA Solar Update

    Thanks so much to Tomas Hood, NW7US, who wrote last week’s bulletin while K7RA was in California at dance camp. Tomas writes the weekly propagation column for CQ magazine, and he has an excellent Web site devoted to propagation. Tomas mentioned that the A
    Learn More

  • 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
    Learn More

  • 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
    Learn More

  • sunspot031110

    03/12/2010 | The K7RA Solar Update

    We experienced a bit of a scare this week when four days went by without sunspots. That's right -- for the first time in three months, we saw more than a single day with a sunspot number of 0, and that last period was back during November 23-December 8.
    Learn More

  • sunspot021810

    02/19/2010 | The K7RA Solar Update

    We've now observed sunspots continuously for the past 30 days -- certainly a turnaround from the quiet conditions of the past few years. In fact, in 10 weeks, we have seen only three days with no sunspots: December 25, January 6 and January 19.
    Learn More

  • sunspot121109

    12/11/2009 | The K7RA Solar Update

    Finally! A sunspot appeared on Wednesday, December 9, giving us a daily sunspot number of 13, following 16 days of no sunspots. And on December 10, the sunspot number was 13. The new group is number 1034, and it is a Solar Cycle 24 spot, as all sunspots h
    Learn More

  • 11/13/2009 | The K7RA Solar Update

    Sunspot region 1029 disappeared after October 30, but not because it faded away -- it was transiting over our Sun's western horizon on its trip around the back side. Six days after it was gone, a new region -- region 1030 -- appeared for several days, Nov
    Learn More