Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update November 29, 1999 at 01:25 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 28. Solar wind speed ranged between 338 and 455 km/sec. A weak coronal stream based disturbance arrived at ACE at 16h UTC. Solar flare activity was moderate. Solar flux was 174.8, the planetary A index was 7 (3-hour Kp indices: 2232 1322, Boulder K indices: 2232 2222). Region 8771 was mostly unchanged and produced several M flares. A major flare is possible over the next day as the region is rotating behind the west limb. Region 8772 decayed and could become spotless today. Region 8773 was mostly quiet and stable, the region will rotate off the visible disk on Nov.30. Region 8774 decayed into spotless plage. Region 8776 was quiet and stable and will rotate over the west limb today. Region 8778 developed further and is capable of minor M class flaring. Region 8779 was quiet and stable and will rotate off the visible disk today. Region 8780 was quiet and stable. Region 8781 developed quickly and has minor M class flaring potential. Region 8782 developed slowly and could produce C flares. SOHO is currently experiencing a problem. No data from the spacecraft will be available until the problem is resolved. Flares and CMEs 8 C flares and 4 M flares were recorded on November 28. Region 8771 produced an M3.5 flare at 01:46 UTC, an M1.1 flare at 05:57 UTC, an M1.4 flare at 18:15 UTC and an M1.6 long duration event peaking at 19:17 UTC. The background x-ray flux is at the class C2 level. Coronal holes A well defined coronal hole in the northern hemisphere was at the central meridian on November 26-27. A coronal hole in the southern hemisphere will rotate into a geoeffective position December 2-4. Forecast The geomagnetic field is expected to be quiet to active on November 29-30. If the CME observed on Nov.26 impacts Earth today, active to major storm conditions would be likely. Low frequency (below 2 MHz) radio wave propagation along east-west paths over high and upper middle latitudes is generally fair. 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 8771 991117 6 S15W85 0170 EAO 8772 991118 1 N07W55 0000 AXX 8773 991119 3 S12W71 0020 BXO 8774 991119 N20W47 plage 8776 991120 3 S26W83 0090 DAO 8777 991121 S27W51 plage 8778 991121 31 S14W33 0200 EAI beta-gamma 8779 991124 1 S10W83 0040 HAX 8780 991124 2 S11W03 0000 AXX 8781 991124 27 S13E22 0170 DAI 8782 991127 9 N10W13 0040 CSO Total number of sunspots: 83 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 193.6 (1) 191.7 (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]