Solar Terrestrial Activity Report [Image] Last update October 12, 2002 at 04:35 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, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update October, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update October 2, 2002)] [Historical solar and geomagnetic data charts 1954-2002 (last update August 16, 2002)] Recent activity The geomagnetic field was quiet to unsettled on October 11. Solar wind speed ranged between 339 and 398 km/sec. Solar flare activity was low. Solar flux was 179.4, the planetary A index was 8 (S.T.A.R. calculated average value based on three hour Ap indices: 9.9). Three hour interval K indices: 22233222 (planetary), 22233211 (Boulder). The background x-ray flux is at the class B7 level. At midnight there were 14 spotted regions on the visible disk, 3 of which were not yet numbered. 10 C class events were recorded during the day. Spotless region 10143 was the source of a long duration C3.7 event peaking at 17:07 UTC. Region 10139 decayed as the large penumbra lost some of its area. The negative polarity area in the south is currently about to be split by a rapidly emerging positive polarity area. M class flares are possible. Flares: C1.2 at 01:53, C1.1 at 04:40, C2.4 at 08:35, C1.7 at 09:35 and C1.7 at 23:41 UTC. Region 10140 was quiet. The region lost most of the small spots it had gained one day earlier. Region 10142 decayed and could soon become spotless. Region 10144 decayed slowly and quietly. Region 10145 was quiet and stable. Region 10146 decayed slowly and quietly. Region 10148 was quiet and stable. Region 10149 developed quickly with many new spots emerging in the southern section of the region. The new spots could actually be argued to be a separate region. Minor M class flares are possible. Flare: C1.3 at 14:21 UTC. Region 10152 decayed and is spotless early on Oct.12. Region 10154 developed a small spot northeast of the main spot. The region was quiet. New region 10155 emerged in the southwest quadrant. New region 10156 emerged in the northeast quadrant on Oct.10 and was numbered on Oct.11. The region has decayed slowly over the last day. Spotted regions not yet numbered: 1. A new region emerged on Oct.10 west of region 10149 and was located at N17E38 at midnight. 2. A new region emerged in the northeast quadrant and was located at N15E60 at midnight. 3. A new region emerged in the southwest quadrant and was located at S06W19 at midnight. This may be the same region which had several small spots earlier this week (emerged on Oct.5) but was spotless on Oct.10. Coronal mass ejections (CMEs) October 9: No obviously geoeffective CMEs were observed. Coronal holes An extension of the northern polar coronal hole could rotate into a geoeffective position on October 11 and cause an increase in geomagnetic activity on October 14-15. Forecast The geomagnetic field is expected to be quiet to unsettled on October 12-13 and quiet to active on October 14-15. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is poor but will likely improve to fair to poor by the end of Oct.12. 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) SEC Solar Date number Location region numbered of at Area Classification Comment spots midnight 10139 2002.10.02 17 N09W46 0590 DKI beta-gamma-delta 10140 2002.10.04 4 S08W11 0180 CSO 10141 2002.10.05 S07W62 plage 10142 2002.10.05 1 N05W17 0000 AXX 10143 2002.10.07 S16W87 plage 10144 2002.10.07 12 N12W10 0110 DSO 10145 2002.10.08 1 N13E36 0070 HSX 10146 2002.10.09 1 S09W05 0020 HSX 10147 2002.10.09 S03E12 plage 10148 2002.10.09 1 S20E43 0040 HSX 10149 2002.10.09 12 N15E48 0220 DSI classification should be DAI 10150 2002.10.09 S09W32 plage 10151 2002.10.09 S14E24 plage 10152 2002.10.10 2 N20W29 0010 DRO now spotless 10153 2002.10.10 S05E34 plage 10154 2002.10.10 2 S13E55 0030 CSO 10155 2002.10.11 2 S09W53 0030 CSO 10156 2002.10.11 3 N09E10 0010 BXO ? emerged (2) N17E38 0010 AXX 2002.10.10 ? emerged (1) N15E60 0010 HRX 2002.10.11 ? emerged (1) S06W19 0010 AXX 2002.10.11 Total number of sunspots: 58 Monthly solar data Average Month solar International sunspot Smoothed sunspot flux at number number Earth 2000.04 184.2 125.5 120.8 cycle 23 sunspot max. 2000.07 202.3 170.1 119.8 2001.09 233.2 150.7 114.1 (+0.5) 2001.10 207.6 125.5 114.0 (-0.1) 2001.11 210.6 106.5 115.5 (+1.5) 2001.12 235.1 132.2 114.6 (-0.9) 2002.01 226.6 114.1 113.5 (-1.1) 2002.02 205.0 107.4 114.7 (+1.2) 2002.03 179.5 98.4 113.4 (-1.3) 2002.04 189.8 120.4 (109.7 predicted, -3.7) 2002.05 178.4 120.8 (105.9 predicted, -3.8) 2002.06 148.7 88.5 (101.4 predicted, -4.5) 2002.07 173.5 99.9 (96.5 predicted, -4.9) 2002.08 183.6 116.4 (92.5 predicted, -4.0) 2002.09 175.8 109.3 (88.7 predicted, -3.8) 2002.10 158.5 (1) 51.1 (2) (84.6 predicted, -4.1) 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 25-45% 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]