Solar Terrestrial Activity Report [Image] Last update November 19, 2000 at 05:45 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 18. Solar wind speed ranged between 324 and 413 km/sec. A weak coronal stream based disturbance started at about 14h UTC and was in progress for the remainder of the day. Solar flare activity was moderate. Solar flux was 177.1, the planetary A index was 6 (3-hour K indices: 0011 2233, Boulder K indices: 0000 0222). Region 9227 decayed and is rotating off the visible disk. Region 9229 was quiet and stable. Region 9231 remained fairly complex and could produce further minor M class flares. Region 9232 was quiet and decayed slowly. Region 9233 decayed further and was quiet. Region 9234 was quiet and stable. Region 9235 developed slowly and could produce further minor M class flares. New region 9236 rotated into view at the northeast limb and may be capable of minor M class flaring. New region 9237 emerged in the northwest quadrant. Comment added at 14:33 UTC on November 18: Region 9131 produced an M1.5 flare at 11:00 UTC, it is not yet known if there was a CME associated with this event (LASCO images haven't been updated since late on Nov.17). Region 9135 was the source of a long duration M1.5 event peaking at 13:25 UTC. A moderately strong type II radio sweep was observed with this event and there may well have been produced a geoeffective CME, which could impact Earth on November 21. A weak coronal stream is in progress and could disturb the geomagnetic field slightly for the remainder of the day. Flares and CMEs A total of 15 C and 2 M class events were recorded on November 18. Region 9227 produced a C3.7 flare at 00:18 and a C3.8/1F flare at 02:34 UTC. Region 9235 generated a C1.5 flare at 01:47, a C3.2 flare at 03:07, a C2.1 flare at 07:09 and a long duration M1.5/1F event peaking at 13:25 UTC. This event was accompanied by a moderately strong type II sweep and likely a geoeffective CME (this is uncertain due to the unavailability of LASCO images covering the hours after the event). The CME could impact Earth on November 21 and cause a geomagnetic disturbance reaching the active to minor storm level. The background x-ray flux is at the class B8 level. Coronal holes A small coronal hole in the southern hemisphere will be 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 19-20 and quiet to minor storm on November 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 9227 20001108 3 S09W85 0100 CSO 9229 20001110 3 N08W35 0050 CSO 9231 20001113 37 S24E05 0200 FAI beta-gamma 9232 20001113 5 N23E07 0020 CSO 9233 20001114 1 N11E22 0010 HAX 9234 20001115 3 N19W21 0010 BXO 9235 20001116 21 N12E34 0150 DSO beta-gamma 9236 20001118 4 N19E71 0120 DSO 9237 20001118 4 N10W19 0020 CSO Total number of sunspots: 81 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) 2000.11 170.0 (1) 91.8 (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]