Solar Terrestrial Activity Report [Image] Last update November 24, 2000 at 05:30 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 1, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update November 1, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update November 1, 2000)] [Historical solar and geomagnetic data charts 1954-2000 (last update October 20, 2000)] Recent development The geomagnetic field was quiet to unsettled on November 23. Solar wind speed ranged between 281 and 359 km/sec. Solar flare activity was moderate. Solar flux was 205.3, the planetary A index was 7 (3-hour K indices: 1312 3321, Boulder K indices: 1413 3211). Region 9231 will likely continue to produce C class flares, M class flares are possible. Region 9232 was quiet and stable. Region 9233 reemerged with a few spots. Region 9235 decayed slowly and was quiet. Region 9236 became very complex as the area of opposite polarity very near and partly inside the huge penumbra containing the leader spot began to encircle that penumbra. M and X class flares are possible. Region 9237 decayed into spotless plage, as did region 9238. Region 9239 was quiet and stable. Region 9240 was mostly quiet but could produce C and M class flares. New region 9241 emerged in the northwest quadrant. Flares and CMEs A total of 11 C and 1 M class events were recorded on November 23. Region 9231 produced a C3.3 flare at 02:43, a C2.9 flare at 04:10, a C2.5 flare at 08:31, a C2.4 flare at 09:23, a C2.5 flare at 09:40, a C2.6 flare at 13:08 and a C7.5/1N flare at 14:24 UTC. Region 9238 was at the center of a fairly large filament eruption which recorded as a long duration C5.4/1F event and peaked at 05:47 UTC. A full halo CME was observed in LASCO images and the CME should impact Earth between noon on November 25 and noon on November 26. Region 9236 generated a C2.3 flare at 18:24 and a long duration M1.0 event peaking at 23:18 UTC. Region 9239 was the source of a long duration C7.9 event which peaked at 20:43 UTC. Region 9236 was the source of an impulsive major X2.0/3B flare at 05:02 UTC on November 24. A CME is likely to have been produced and could impact Earth between on November 26, however, this will not be confirmed until LASCO images are available. November 22: Region 9237 produced a C7.0/1N flare at 16:21 UTC, the flare was accompanied by a weak type II sweep. With the region only one day's rotation from the central meridian, a weak CME associated with the flare could easily be geoeffective and cause a minor geomagnetic disturbance on November 25. The background x-ray flux is at the class C2 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to active on November 24-25 and unsettled to severe storm on November 26. A CME associated with the X2 event on Nov.24 could arrive on Nov.25 and start a major disturbance. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is 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 9231 20001113 20 S23W62 0320 FAI beta-gamma-delta 9232 20001113 1 N25W58 0000 AXX 9233 20001114 3 N15W41 0070 CSO 9234 20001115 N19W86 plage 9235 20001116 12 N14W35 0090 FAO 9236 20001118 17 N21E06 0390 EKO beta-gamma-delta 9237 20001118 N09W86 plage 9238 20001120 S22W48 plage 9239 20001121 1 S21E49 0140 HSX 9240 20001122 5 N09E58 0250 DSO 9241 20001123 2 N21W19 0020 DRO Total number of sunspots: 61 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.10 164.8 116.7 107.8 (+5.5) 1999.11 191.5 133.2 110.9 (+3.1) 1999.12 169.8 84.6 111.0 (+0.1) 2000.01 158.1 90.1 112.8 (+1.8) 2000.02 174.1 112.9 116.6 (+3.8) 2000.03 208.2 138.5 119.8 (+3.2) 2000.04 184.2 125.3 120.7 (+0.9) 2000.05 184.9 120.8 (119.6 predicted, -1.1) 2000.06 179.8 124.9 (120.3 predicted, +0.7) 2000.07 202.3 169.1 (122.4 predicted, +2.1) 2000.08 163.0 130.5 (122.5 predicted, +0.1) 2000.09 182.1 109.9 (121.0 predicted, -1.5) 2000.10 167.4 100.1 (119.8 predicted, -1.2) 2000.11 173.7 (1) 117.7 (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 noted in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]