Solar Terrestrial Activity Report [Image] Last update October 19, 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 October 2, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update October 2, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update October 2, 2000)] [Historical solar and geomagnetic data charts 1954-2000 (last update August 10, 2000)] Recent development The geomagnetic field was quiet to unsettled on October 18. Solar wind speed ranged between 412 and 518 km/sec. Solar flare activity was low. Solar flux was 151.1, the planetary A index was 8 (3-hour K indices: 2213 3222, Boulder K indices: 2213 3222). Region 9190 was quiet and stable. Region 9194 decayed fairly quickly and was quiet, the region produced a C flare early on October 19. Region 9198 was quiet and stable. Region 9199 developed slowly and could produce further C class flares. Region 9200 was quiet and stable but could produce C class flares. Region 9201 developed slowly and may be capable of minor M class flare production. New region 9202 was, questionably, split off from region 9199. Flares and CMEs A total of 4 C class events were recorded on October 18. Region 9199 produced a C1.4 flare at 22:51 UTC. The background x-ray flux is at the class B6 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to unsettled on October 19-21. 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 no. Location at region numbered sunspots midnight Area Classification Comment 9189 20001008 N14W71 plage 9190 20001008 5 S14W60 0030 CSO 9191 20001010 N18W36 plage 9194 20001012 7 S10W16 0030 DAO 9197 20001012 N25W10 plage 9198 20001014 8 S30E13 0110 DSO 9199 20001015 10 N12E24 0050 ESO beta-gamma 9200 20001016 10 S17E32 0110 DAO 9201 20001017 12 N17E57 0110 DAI 9202 20001018 6 N14E26 0040 CSO Total number of sunspots: 58 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.09 135.7 71.5 102.3 (+4.8) 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 (121.7 predicted, +1.9) 2000.05 184.9 120.8 (122.5 predicted, +0.8) 2000.06 179.8 124.9 (124.1 predicted, +1.6) 2000.07 202.3 169.1 (126.2 predicted, +2.1) 2000.08 163.0 130.6 (124.8 predicted, -1.4) 2000.09 182.1 109.9 2000.10 164.4 (1) 82.6 (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]