Solar Terrestrial Activity Report [Image] Last update November 10, 2000 at 05:50 UTC. Important update posted at 06:53 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 9. Solar wind speed ranged between 427 and 595 km/sec and was under the influence of a weak coronal stream during the latter half of the day. Solar flare activity was moderate. Solar flux was 166.2, the planetary A index was 11 (3-hour K indices: 3111 3333, Boulder K indices: 3112 3432). Region 9213 rotated off the visible disk. Region 9218 was quiet and stable, the region will rotate over the west limb on November 11. Region 9219 was quiet and stable. Region 9220 developed slowly could produce C flares. Region 9221 decayed slowly and is not likely to produce another minor M class flare. Regions 9222 and 9223 were quiet and stable. Region 9224 decayed into spotless plage. Region 9225 was mostly quiet and stable, occasional C class flares are possible. Region 9227 developed slowly and may be capable of C and minor M class flare production. New region 9228 emerged in the northeast quadrant. Comment added at 06:53 UTC on November 10: Although I had expected to post an update today I was a bit surprised I would have to post it so soon. A major solar wind shock was observed at SOHO at 06:00 UTC. Solar wind speed increased abruptly from 610 to 880 km/sec, then seemed to settle down around 780 km/sec. A CME arriving after only 31 hours in transit from a solar limb event is very impressive and unusual. It is difficult to tell how strong the geomagnetic disturbance could become. As a weak coronal stream was in progress during the time of the arrival of the CME form the eruption on November 8 this could decrease the intensity of the storm, still minor to severe storm is likely. Flares and CMEs A total of 1 C and 3 M class events were recorded on November 9. Region 9221 produced an M1.0 flare at 16:13 UTC, possibly triggered by a filament eruption within the region. The event occurred near the center of the solar disk and a small CME is likely to impact Earth on November 12. Region 9125 generated a C6.4/1F flare at 21:22 UTC. This event was associated with a weak type II sweep and probably a CME which has only a minor chance of impacting Earth. November 8: Regions 9212, 9213 and 9218 all contributed to a major M7.4/3F long duration event peaking at 23:23 UTC. The event started at 22:40 UTC and 1 hour later a large proton event was observed at Earth. The above 10 MeV proton flux appears to have peaked at above 13000 pfu on November 9. A large and fast full halo CME was associated with the major event and could impact Earth anytime between early on November 10 and noon on November 11. The background x-ray flux is at the class C1 level. Coronal holes A trans equatorial coronal hole was in a geoeffective position on November 8-10 and could cause unsettled to major storm conditions on November 11-13. Forecast The geomagnetic field is expected to be initially quiet to unsettled on November 10. A large CME could impact Earth during the day and cause active to severe storm conditions. Quiet to major storm is possible on November 11 as a coronal stream arrives. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is useless and will remain so until the currently strong polar cap absorption event ends. 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 9212 20001028 N10W86 plage 9213 20001028 1 N04W92 0060 HSX 9218 20001101 1 N20W72 0140 HAX 9219 20001101 1 N06W42 0110 HSX 9220 20001101 12 N12W29 0050 DAO 9221 20001104 8 S14E06 0080 CAO 9222 20001105 1 N16W92 0030 HRX 9223 20001105 2 S18E20 0080 HSX 9224 20001107 N30W86 plage 9225 20001107 3 S21W44 0050 CRO 9227 20001108 16 S13E38 0120 DAO 9228 20001109 4 N20E29 0010 BXO Total number of sunspots: 49 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) 2000.11 186.4 (1) 51.5 (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]