Solar Terrestrial Activity Report [Image] Last update October 31, 2001 at 03:45 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update October 3, 2001)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update October 3, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update October 3, 2001)] [Historical solar and geomagnetic data charts 1954-2001 (last update October 16, 2001)] Recent development The geomagnetic field was quiet to unsettled on October 30. Solar wind speed ranged between 357 and 416 km/sec. Solar flare activity was moderate. Solar flux was 212.5 (the 17h UTC measurement was used because a long duration event enhanced the value at 20h UTC), the planetary A index was 8 (3-hour K indices: 2332 2222, Boulder K indices: 2323 2111). Region 9672 rotated off the visible disk early in the day. Region 9673 was quiet and stable and rotated over the northwest limb. Region 9676 decayed and could become spotless today. Region 9678 decayed significantly and was quiet. Region 9679 decayed and could become spotless today. Region 9681 decayed and appeared to be spotless early on October 31. Region 9682 developed further. Major proton flares, perhaps even X10+ flares, are possible from this region. Region 9683 decayed and could become spotless today. Region 9684 was mostly quiet and did not change signifcantly. M class flares are possible. A small, new region has rotated into view at the northeast limb. An interesting region is about to rotate into view at the southeast limb. The region could be capable of producing major flares. Flares and CMEs A total of 12 C and 1 M class events were recorded on October 30. Region 9682 produced an impulsive M3/1N flare at 08:34, a C6.6 flare at 10:15, a C6.7 flare at 11:24, a C4.4 flare at 11:46, a C7.4/1N flare at 12:20, a C5.0 flare at 14:57, a C3.6 flare at 15:19 and a C7.0 flare at 16:57 UTC. Region 9684 generated a C3.5 flare at 12:04 UTC. A region behind the northwest limb was the source of a C6.0 flare at 03:23 UTC. A region behind the southeast limb was the origin of a long duration C9.2 event peaking at 20:32 UTC and an accompanying CME. The background x-ray flux is at the class C1 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 31 and November 1. 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 Location region numbered no. at Area Classification Comment sunspots midnight 9672 2001.10.18 1 S16W92 0110 HAX 9673 2001.10.18 1 N05W89 0030 HSX 9675 2001.10.20 S12W64 plage 9676 2001.10.20 1 N15W62 0020 HSX 9677 2001.10.21 N24W62 plage 9678 2001.10.23 21 N07W47 0490 EKI beta-gamma 9679 2001.10.23 7 S10W34 0020 BXO 9680 2001.10.23 N22W35 plage 9681 2001.10.25 1 S23W65 0010 AXX 9682 2001.10.25 59 N12E04 1130 EKC beta-gamma-delta 9683 2001.10.26 4 N28W28 0020 BXO 9684 2001.10.27 20 N05E41 0470 DKO beta-gamma Total number of sunspots: 115 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 2000.04 184.2 125.5 120.8 cycle 23 sunspot max. 2000.07 202.3 170.1 119.8 2000.09 182.1 109.7 116.3 (-2.3) 2000.10 167.4 99.4 114.5 (-1.8) 2000.11 178.8 106.8 112.7 (-1.8) 2000.12 173.6 104.4 112.0 (-0.7) 2001.01 166.6 95.6 108.7 (-3.3) 2001.02 146.6 80.6 104.1 (-4.6) 2001.03 177.7 113.5 104.8 (+0.7) 2001.04 177.7 107.7 (107.7 predicted, +2.9) 2001.05 147.1 96.6 (108.1 predicted, +0.4) 2001.06 173.0 134.0 (106.3 predicted, -1.8) 2001.07 131.3 82.2 (105.1 predicted, -1.2) 2001.08 162.9 106.8 (105.7 predicted, +0.6) 2001.09 233.2 150.7 (105.1 predicted, -0.6) 2001.10 207.2 (1) 190.2 (2) (102.3 predicted, -2.8) 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]