Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update November 19, 1999 at 01:20 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 18. Solar wind speed ranged between 448 and 617 km/sec under the influence of a weak coronal stream. Solar flare activity was moderate. Solar flux was 217.9, the planetary A index was 12 (3-hour Kp indices: 2233 3333, Boulder K indices: 2223 3333). Region 8759 decayed but could still be capable of producing a minor M flare. Region 8763 was quiet and stable. Region 8765 was mostly unchanged and is capable of producing a major proton flare. Region 8766 did not change significantly and remains capable of producing a major flare. Region 8767 decayed into spotless plage. Region 8768 lost several spots and seems to have peaked in its development. The region was quiet. Region 8769 gained a few spots and was quiet. Region 8770 developed slowly and is likely to produce further C flares. Region 8771 was fairly active and is capable of minor M class flaring. New region 8772 rotated partly into view at the northeast limb. Further active regions should rotate into view at both the northeast and southeast limbs over the next couple of days. The above 10 MeV proton flux has increased to a level of 1 pfu early on November 19. Flares and CMEs 5 C flares and 1 M flare were recorded on November 18. Solar region 8759 was the source of a C7.5 flare at 08:07 UTC. Region 8765 produced a C2.7 flare at 17:14 UTC and a C8.3/1F flare at 19:03 UTC. The latter flare may have been a weak proton flare as well. Region 8770 generated a C3.5 flare at 18.52 UTC. Region 8771 produced the single M flare of the day, an M1.4/1F event at 01:49 UTC. 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. 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 unsettled to active early on November 19, active to major storming is possible later in the day and on November 20 following a CME impact. 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 8759 991106 8 N13W66 0120 DAO 8761 991108 N20W80 plage 8763 991110 2 S13W35 0010 BXO 8765 991111 35 S12W20 1280 EKC beta-gamma-delta 8766 991113 20 N18E02 0300 EAI beta-gamma 8767 991114 N42W81 plage 8768 991114 10 N17W24 0180 EAO 8769 991115 4 S10E37 0070 CAO 8770 991116 9 S13W51 0110 DAO 8771 991117 15 S14E46 0170 FAO 8772 991118 1 N05E71 0020 HAX Total number of sunspots: 104 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 196.2 (1) 131.6 (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]