Solar Terrestrial Activity Report [Image] Last update October 27, 2000 at 05:25 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update 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 October 20, 2000)] Recent development The geomagnetic field was quiet to unsettled on October 26. Solar wind speed ranged between 349 and 411 km/sec. Solar flare activity was low. Solar flux was 171.0, the planetary A index was 7 (3-hour K indices: 2223 2212, Boulder K indices: 2233 3212). Region 9198 decayed slowly and was quiet, the region will rotate off the visible disk early today. Region 9199 was quiet and stable and has rotated off the visible disk. Region 9201 decayed further and was quiet. Region 9206 was quiet and stable. Region 9207 decayed slowly and was quiet. Region 9208 decayed slowly and was quiet. Region 9209 developed and could produce M class flares. New region 9210 rotated into view at the southeast limb. Flares and CMEs A total of 6 C class events were recorded on October 26. Region 9209 produced a C1.8 flare at 23:01 UTC. October 25: A very long duration C4.0 event began at 08:45, peaked at 11:25 and ended at 15:21 UTC. The source of this event was a large filament eruption between regions 9201 and 9199 in the northwest quadrant, with the major part of the eruption being near region 9199 at the northwest limb. A full halo CME was observed in LASCO images, the CME will impact Earth, most likely on October 28. The background x-ray flux is at the class B9 level. Coronal holes A small well placed coronal hole in the southern hemisphere was in a geoeffective position on October 26. Forecast The geomagnetic field is expected to be quiet to active on October 27 and unsettled to major storm on October 28. A coronal stream could cause unsettled to active conditions on October 29. 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 9198 20001014 1 S29W85 0030 HSX 9199 20001015 1 N07W94 0030 HSX 9200 20001016 S13W71 plage 9201 20001017 8 N19W48 0070 CAO 9202 20001018 N13W76 plage 9204 20001020 N10W64 plage 9205 20001021 N36W85 plage 9206 20001023 5 N21E14 0010 BXO 9207 20001023 7 S19E27 0090 DSO 9208 20001023 3 S08E39 0050 CSO 9209 20001025 7 S24E59 0180 DSO 9210 20001026 1 S30E74 0070 HSX Total number of sunspots: 33 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 (121.0 predicted, +1.2) 2000.05 184.9 120.8 (121.3 predicted, +0.3) 2000.06 179.8 124.9 (122.8 predicted, +1.5) 2000.07 202.3 169.1 (124.9 predicted, +2.1) 2000.08 163.0 130.5 (125.0 predicted, +0.1) 2000.09 182.1 109.9 2000.10 163.7 (1) 115.6 (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]