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Solar Activity Report for 7/21/04

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  • David
    ** Aurora Watch In Effect ** Sunspot region 652 produced off a long duration M-8.6 flare on the 20th, which fired off a nice, full-halo CME, as can be seen
    Message 1 of 1 , Jul 21, 2004
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      ** Aurora Watch In Effect **

      Sunspot region 652 produced off a long duration M-8.6 flare on the
      20th, which fired off a nice, full-halo CME, as can be seen here :
      http://science.nasa.gov/spaceweather/images2004/20jul04/cme_c3_big.gif
      . No question about it, this one is headed for us. Arrival is
      expected sometime during the night of the 22nd. As always, the degree
      of effect will depend upon which way the Interplanetary Magnetic Field
      being carried along by the CME is oriented. In anticipation of the
      CME's arrival, an aurora watch is in effect. Skywatchers in the
      higher latitudes should definitely keep an eye out for aurora Thursday
      night. As I write this, an M-9 class flare is in progress. It is
      beginning to look like it will also be a long duration event, but not
      as long as the M-8.6 flare. We should be able to see tomorrow whether
      or not another CME is on the way.

      The current solar and geomagnetic conditions are :

      NOAA sunspot number : 162
      SFI : 172
      A index : 4
      K index : 2

      Solar wind speed : 376.9 km/sec
      Solar wind density : 2.1 protons/cc
      Solar wind pressure : 0.5 nPa

      IMF : 5.1 nT
      IMF Orientation : 0.8 nT north

      GOES-12 Background X-ray Flux level : B6

      Conditions for the last 24 hours :
      Space weather for the past 24 hours has been moderate. Radio blackouts
      reaching the R2 level occurred.

      Forecast for the next 24 hours :
      Space weather for the next 24 hours is expected to be minor. Radio
      blackouts reaching the R1 level are expected.

      Solar activity forecast :
      Solar activity is expected to be predominantly moderate. However,
      there is still a possibility for major flare activity from Region 652.

      Geomagnetic activity forecast :
      The geomagnetic field is expected to be quiet to unsettled tomorrow
      (22 July), with active to minor storm conditions expected on day two
      (23 July) from the possible effects of a CME observed on LASCO imagery
      on 20 July. Geomagnetic activity should return to quiet to unsettled
      conditions on 24 July.

      Recent significant solar flare activity :
      22-Jul-2004 0032Z M9.1
      20-Jul-2004 1232Z M8.6
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