Solar Terrestrial Activity Report [Image] Last update February 9, 2001 at 04:35 UT. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update February 2, 2001) - Cycle 23 peaked in April 2000?] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update February 2, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update February 2, 2001)] [Historical solar and geomagnetic data charts 1954-2000 (last update January 18, 2001)] Recent development The geomagnetic field was quiet to unsettled on February 8. Solar wind speed ranged between 397 and 456 km/sec. Solar flare activity was low. Solar flux was 156.5, the planetary A index was 6 (3-hour K indices: 1223 0223, Boulder K indices: 1123 1213). Region 9330 decayed slowly and was quiet. Region 9334 decayed and was quiet. Region 9335 decayed slowly and was mostly quiet. Region 9337 decayed quickly and could become spotless by the end of today. Region 9338 was quiet and stable. Region 9339 decayed and was quiet. Region 9340 reemerged with a couple of spots, but seems to have decayed into spotless plage again. Region 9341 was quiet and stable. New region 9344 emerged in the northeast quadrant. New region 9345 emerged in the southeast quadrant. A new region has rotated into view at the east limb. Flares and CMEs Only 1 C class event was recorded on February 7. Region 9335 produced a C1.1 flare at 20:30 UT. The background x-ray flux is at the class B4 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to unsettled on February 9-10. 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 9329 2001.01.29 S09W79 plage 9330 2001.01.30 7 N26W47 0080 CAO 9334 2001.02.01 16 N12W14 0110 EAI 9335 2001.02.03 11 N09E01 0070 DSI 9336 2001.02.03 S09W67 plage 9337 2001.02.03 5 S28E12 0020 CSO 9338 2001.02.04 6 S18E10 0020 BXO 9339 2001.02.04 13 S11E21 0210 EAO 9340 2001.02.05 2 S11W36 0000 AXX 9341 2001.02.06 3 S08W03 0010 BXO 9342 2001.02.06 S26E29 plage 9343 2001.02.07 N03W05 plage 9344 2001.02.08 3 N31E13 0020 BXO 9345 2001.02.08 2 S20E19 0000 AXX Total number of sunspots: 68 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.11 191.5 133.2 111.0 (+3.2) 1999.12 169.8 84.6 111.1 (+0.1) 2000.01 158.1 90.1 112.9 (+1.8) 2000.02 174.1 112.9 116.8 (+3.9) 2000.03 208.2 138.5 119.9 (+3.1) 120.8 (+0.9) 2000.04 184.2 125.5 cycle 23 peak candidate 2000.05 184.9 121.6 119.0 (-1.8) 2000.06 179.8 124.9 118.7 (-0.3) 2000.07 202.3 170.1 119.8 (+1.1) 2000.08 163.0 130.5 (119.7 predicted, -0.1) 2000.09 182.1 109.7 (118.4 predicted, -1.3) 2000.10 167.4 100.1 (116.7 predicted, -1.7) 2000.11 178.8 106.5 (114.8 predicted, -1.9) 2000.12 173.6 104.5 (112.2 predicted, -2.6) 2001.01 166.6 95.7 (108.7 predicted, -3.5) 2001.02 161.8 (1) 43.3 (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]