Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update November 1, 1999 at 04:15 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update October 2, 1999)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update October 2, 1999)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update October 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 October 31. Solar wind speed ranged between 351 and 439 km/sec. A solar wind shock was observed at approximately 07h UTC. The interplanetary magnetic field was mostly northerly following the shock passage and resulted in only a minor increase in geomagnetic activity. Solar flare activity was low. Solar flux was 160.4, the planetary A index was 10 (3-hour Kp indices: 2233 3323, Boulder K indices: 1232 1333). Region 8739 decayed slowly and will be rotating off the visible disk today. Region 8741 decayed slowly and was quiet. Region 8742 decayed and was quiet. Region 8743 was mostly unchanged and quiet. Region 8744 reemrged with a couple of spots. Region 8745 decayed slowly and was quiet. Region 8747 decayed slowly and could produce further C class flares. Region 8748 was quiet and stable. Region 8749 was the most active flare region and should produce further C class flares. Region 8750 was quiet and stable and appears to be spotless early on November 1. Region 8751 was quiet and stable. Flares and CMEs 9 C flares were recorded on October 31 with region 8749 producing 6 of the events and region 8747 generating 2 C flares. The most significant event of the day was a moderate duration C7.6/1N flare from region 8749 peaking at 07:02 UTC. It was associated with a weak type II sweep and likely a coronal mass ejection. LASCO images of the event are unavailable, however, taking the position of the region into account, the CME could impact the earth on November 3. The background x-ray flux is at the class B5 level. Coronal holes No obvious coronal holes are currently in or approaching a geoeffective position. Forecast The geomagnetic field is expected to be quiet to active on November 1 and quiet to unsettled on November 2. There is a possibility of a CME impact on November 3. Should that happen unsettled to minor storming would be likely. Low frequency (below 2 MHz) radio wave propagation along east-west paths over high and upper middle latitudes is generally 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 no. Location at region numbered sunspots midnight Area Classification Comment 8739 991020 8 S11W78 0180 FAO 8741 991022 7 S25W54 0140 EAC 8742 991023 20 N09W24 0200 EAO 8743 991025 5 S15W61 0110 DAO 8744 991025 2 N10W38 0010 AXX 8745 991026 6 S15E00 0110 DAO 8746 991027 S16W24 plage 8747 991028 12 N11E17 0160 DAO 8748 991029 5 N19W20 0010 BXO 8749 991029 15 S18E15 0060 DSO 8750 991029 3 S16W18 0000 BXO 8751 991030 1 N21E54 0040 HSX Total number of sunspots: 84 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 9807 114.0 66.6 65.5 (+3.0) 9808 136.0 92.2 67.8 (+2.3) 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 63.9 (84.9 predicted, +1.1) 9905 148.4 106.4 (89.5 predicted, +4.6) 9906 169.8 137.4 (93.6 predicted, +4.1) 9907 165.6 113.5 9908 170.7 93.7 9909 135.7 70.6 9910 164.8 (1) 167.0 (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]