Solar Terrestrial Activity Report [Image] Last update November 21, 2000 at 04:35 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 20. Solar wind speed ranged between 350 and 431 km/sec under the influence of a weak coronal stream. Solar flare activity was low. Solar flux was 173.7, the planetary A index was 9 (3-hour K indices: 1132 3331, Boulder K indices: 1132 2311). Region 9229 was quiet and stable. Region 9231 developed slowly during the first half of the day, then decayed and has already lost many of its spots. Minor M class flares are still possible. Region 9232 was quiet and stable, as was region 9233. Region 9234 decayed into spotless plage. Region 9235 was mostly unchanged and could produce minor M class flares. Region 9236 developed slowly and could produce M class flares. Region 9237 decayed slightly and was quiet. New region 9238 emerged in the southwest quadrant near the central meridian. Emissions off the east limb indicate that several regions are approaching the southeast and northeast limbs. Flares and CMEs A total of 5 C class events were recorded on November 20. Region 9231 produced a C1.9 flare at 09:06, a C2.2 flare at 09:38 and a C2.1 flare at 13:20 UTC. November 19-20: Region 9231 was the source of a long duration C7.2 event which began at 23:52 on Nov.19 and peaked at 00:36 UTC on Nov.20. A filament eruption was observed to the west of the region and an associated weak CME has a chance of influencing the geomagnetic field on November 22 or 23. The background x-ray flux is at the class B8 level. Coronal holes A small coronal hole in the southern hemisphere was in a geoeffective position on November 19-20 and could cause a few unsettled to active intervals on November 22-23. Forecast The geomagnetic field is expected to be quiet to unsettled on November 21-22. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is 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 9229 20001110 1 N08W62 0030 HAX 9231 20001113 39 S24W23 0410 FKI beta-gamma 9232 20001113 5 N22W19 0020 CSO 9233 20001114 1 N12W05 0010 HSX 9234 20001115 N19W47 plage 9235 20001116 23 N13E06 0230 EAI beta-gamma 9236 20001118 8 N19E45 0410 EHO 9237 20001118 8 N09W46 0040 CSO 9238 20001120 3 S23W08 0010 CRO Total number of sunspots: 88 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) 2000.11 170.5 (1) 103.2 (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 noted in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]