Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update November 18, 1999 at 03:30 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update November 2, 1999)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update November 2, 1999)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update November 2, 1999)] [Historical solar and geomagnetic data charts 1954-1999] [Experimental solar data chart January 1998-September 1999] Recent development The geomagnetic field was quiet to unsettled on November 17. Solar wind speed is unavailable (until approx. Nov.19 due to the Leonids). A weak coronal stream arrived early in the day but did not manage to produce activity above the unsettled level. Solar flare activity was high. Solar flux was 221.3, the planetary A index was 10 (3-hour Kp indices: 2222 3332, Boulder K indices: 2232 3332). Region 8755 was quiet and stable, the region is rotating off the visible disk. Region 8759 was mostly unchanged and could still produce M class flares. Region 8760 rotated over the west limb. Region 8763 decayed and was quiet. Region 8765 developed further and is a very complex region capable of producing a major proton flare at any time over the next few days. Region 8766 developed further as well and has the potential to produce a major proton flare. Region 8767 was quiet and stable. Region 8768 developed slowly and has minor M flare potential. Region 8769 nearly managed to produce an M flare but is unlikely to be the source of significant flaring, at least not for the next few days. Region 8770 was quiet and stable. New region 8771 was split off from region 8769, the region is capable of minor M class flaring. The above 10 MeV proton flux has increased to slightly above background values. Flares and CMEs 12 C flares and 1 M flare were recorded on November 17. Region 8766 produced the most significant flare of the day, a major M7.4/2B impulsive flare at 09:57 UTC. The flare was accompanied by a strong type IV sweep and a moderately strong type II sweep. The associated coronal mass ejection has a fairly high probability of impacting the sometime between late on November 19 and late on November 20. Region 8765 was the source of a C7.0/1N flare at 09:38 UTC and 4 other C flares. Region 8769 generated a C9.2 flare at 17:43 UTC. Region 8771 produced a C3.2 flare at 08:49 UTC and a C3.8 flare at 20:18 UTC. The latter flare was accompanied by a weak type II sweep. At 01:49 on November 18 region 8771 generated an M1.4 flare. November 16: Region 8766 produced an M3.8/1B flare at 02:46 UTC. It was accompanied by a strong type II sweep and a moderately strong type IV sweep. The associated coronal mass ejection was a partial halo one covering most of the east limb and the north pole. There is a chance this CME could impact the earth on November 19. The background x-ray flux is at the class C1-C2 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions.. Forecast The geomagnetic field is expected to be quiet to unsettled on November 18. CME impacts are possible on November 19 and 20 and could cause active to major storm conditions. Low frequency (below 2 MHz) radio wave propagation along east-west paths over high and upper middle latitudes is generally fair to poor. Coronal holes (1) Coronal mass M and X class flares (3) ejections (2) [Coronal hole indicator][CME indicator] [M and X class flare indicator] 1) Effects from a coronal hole could reach earth within the next 5 days. 2) Material from a CME is likely to impact earth within 96 hours. 3) There is a possibility of either M or X class flares within the next 48 hours. Green: 0-20% probability, Yellow: 20-60% probability, Red: 60-100% probability. Active solar regions (Recent map) Solar Date Actual Location region numbered no. at Area Classification Comment sunspots midnight 8755 991105 1 N22W88 0060 HSX 8758 991106 N18W78 plage 8759 991106 24 N12W58 0180 CAO beta-gamma 8760 991107 1 N17W93 0060 HAX 8761 991108 N20W67 plage 8763 991110 5 S13W20 0010 BXO 8765 991111 41 S12W08 1190 EKC beta-gamma-delta 8766 991113 24 N18E16 0360 EKC beta-gamma 8767 991114 2 N42W68 0020 CSO 8768 991114 18 N17W11 0180 EAI 8769 991115 1 S12E53 0110 HSX 8770 991116 8 S14W37 0050 DSO 8771 991117 13 S13E59 0070 CSO Total number of sunspots: 138 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 9809 138.3 92.9 69.5 (+1.7) 9810 117.2 55.5 70.5 (+1.0) 9811 140.1 74.0 73.0 (+2.5) 9812 150.1 81.9 77.9 (+4.9) 9901 140.6 62.0 82.6 (+4.7) 9902 141.9 66.3 84.6 (+2.0) 9903 126.3 68.8 83.8 (-0.8) 9904 117.2 63.7 85.4 (+1.6) 9905 148.4 106.4 (90.4 predicted, +5.0) 9906 169.8 137.7 (94.6 predicted, +4.2) 9907 165.6 113.5 (99.6 predicted, +5.0) 9908 170.7 93.7 9909 135.7 70.6 9910 164.8 116.4 9911 194.9 (1) 125.2 (2) 1) Running average based on the daily 20:00 UTC solar flux value at 2800 MHz.. 2) Unofficial, accumulated value. The official value is typically 25-40% less. This report has been prepared by Jan Alvestad. It is based partly on my own observations and interpretations, and partly on data from sources in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]