Solar Terrestrial Activity Report [Image] Last update September 9, 2001 at 05:05 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update September 1, 2001)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update September 1, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update September 1, 2001)] [Historical solar and geomagnetic data charts 1954-2001 (last update July 27, 2001)] Recent development The geomagnetic field was quiet to unsettled on September 8. Solar wind speed ranged between 304 and 362 km/sec. Solar flare activity was moderate. Solar flux was 249.5, the planetary A index was 7 (3-hour K indices: 3222 2322, Boulder K indices: 2122 3312). Region 9601 rotated partly onto the northwest limb and will rotate out of view by the end of today. An M flare is possible while the region is near the limb. Region 9605 was quiet and stable. Region 9606 decayed slightly but could still produce minor M class flares. Region 9607 developed slowly and has M class flare potential. Region 9608 developed further and could produce a major flare, an X class flare is a possibility. Magnetograms indicate a delta configuration could be forming. Region 9609 was quiet and stable and will rotate off the visible disk today. Region 9610 developed slowly and could produce M class flares. Region 9611 developed quickly and may be capable of generating an isolated minor M class flare. Region 9612 was quiet and stable Region 9613 was mostly quiet and stable and will rotate off the visible disk on September 10. New region 9614 emerged in the northwest quadrant. New region 9615 emerged in the northeast quadrant. Flares and CMEs A total of 5 C and 2 M class events were observed on September 8. Region 9608 produced an M1.2 flare at 04:57 and a C5.1 flare at 16:45 UTC. Region 9613 generated a C3.5 flare at 12:29 UTC. Region 9601 was the source of an M1.1 long duration event peaking at 19:23 UTC, while region 9607 managed a C4.6 flare at 23:53 UTC. A filament erupted in the northeast quadrant beginning at 20:26 UTC in LASCO EIT images. The eruption does not appear to have been large, and it is not yet certain if a CME was produced. The background x-ray flux is at the class C2 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to unsettled on September 9-10. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is 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 9601 2001.08.27 14 N13W79 0500 EKI beta-gamma 9602 2001.09.01 S07W63 plage 9603 2001.09.02 S08W16 plage area 9605 2001.09.03 2 S18W15 0070 HSX should be 0030 9606 2001.09.03 30 S18W07 0220 EAI beta-gamma 9607 2001.09.04 27 S17E17 0300 EAI beta-gamma 9608 2001.09.05 47 S26E33 0940 FKC beta-gamma 9609 2001.09.06 2 S06W85 0020 HSX 9610 2001.09.06 14 S14E48 0330 EAO 9611 2001.09.07 11 N10W37 0130 DAO 9612 2001.09.07 5 N22E27 0030 DRO 9613 2001.09.07 7 S17W68 0030 BXO 9614 2001.09.08 1 N13W19 0000 HRX 9615 2001.09.08 1 N12E64 0000 AXX Total number of sunspots: 161 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 2000.03 208.2 138.5 119.9 2000.04 184.2 125.5 120.8 cycle 23 sunspot max. 2000.07 202.3 170.1 119.7 2000.08 163.0 130.5 118.6 (-1.1) 2000.09 182.1 109.7 116.3 (-2.3) 2000.10 167.4 99.4 114.5 (-1.8) 2000.11 178.8 106.8 112.8 (-1.7) 2000.12 173.6 104.4 112.1 (-0.7) 2001.01 166.6 95.6 108.8 (-3.3) 2001.02 146.6 80.6 104.1 (-4.7) 2001.03 177.7 113.5 (103.8 predicted, -0.3) 2001.04 177.7 108.2 (104.1 predicted, +0.3) 2001.05 147.1 97.3 (102.6 predicted, -1.5) 2001.06 173.0 134.0 (99.8 predicted, -2.8) 2001.07 131.3 82.2 (98.0 predicted, -1.8) 2001.08 162.9 106.8 (98.5 predicted, +0.5) 2001.09 212.5 (1) 52.6 (2) (97.5 predicted, -1.0) 1) Running average based on the daily 20:00 UT solar flux value at 2800 MHz. 2) Unofficial, accumulated value based on the Boulder (SEC/NOAA) sunspot number. The official international sunspot number 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]