Solar Terrestrial Activity Report [Image] Last update August 30, 2002 at 03:40 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update August 7, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update August 7, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update August 7, 2002)] [Historical solar and geomagnetic data charts 1954-2002 (last update August 16, 2002)] Recent development The geomagnetic field was quiet to unsettled on August 29. Solar wind speed ranged between 415 and 562 km/sec under the decreasing influence of a weak coronal stream. Solar flare activity was moderate. Solar flux was 169.3, the planetary A index was 10 (3-hour planetary K indices: 3212 3333, Boulder K indices: 3111 3322). Region 10084 decayed and was spotless by midnight. Region 10085 decayed slowly and was mostly quiet. Region 10087 decayed slowly but still has a magnetic delta structure in a central penumbra. Occasional minor M class flares are possible. Region 10090 developed quite a few new spots and was quiet. Region 10092 developed slowly and quietly. New region 10093, which emerged in the southeast quadrant on August 27, was finally numbered. The region had decayed into spotless plage by late afternoon. New region 10094 emerged quickly near the southeast limb and could have a small magnetic delta structure. New region 10095 rotated partly into view at the northeast limb. This region appears to have been the source of the increase in solar activity over the last two days. Magnetograms indicate that there is a magnetic delta structure in the northeastern part of the region. The region is slightly cooler compared to one day ago but still has the potential to produce M class flares and perhaps major flares. Flares and CMEs A total of 10 C and 4 M class events was recorded on August 29. Region 10095 produced an M1.6 flare at 02:53, an M1.8 flare at 05:09, an M1.7 flare at 05:19 (not reported by SEC/NOAA, but this was clearly a separate flare in 1 minute x-ray plots) and an M3.2 flare at 12:52 UTC. Region 10085 generated a C4.5 flare at 10:39 UTC. The background x-ray flux is at the class C1 level. Coronal holes A coronal hole in the southeast quadrant will likely rotate into a geoeffective position on August 30. Forecast The geomagnetic field is expected to be quiet to unsettled on August 30 to September 1. On September 2 a coronal stream could begin to influence the field and cause unsettled to active conditions. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is poor but could improve to fair over the next couple of days. 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 area too large, 10084 2002.08.18 1 S17W79 0030 HSX was 0010, now spotless 10085 2002.08.19 3 S08W63 0310 HHX 10086 2002.08.22 S26W63 plage 10087 2002.08.22 26 S08W20 0250 DAI beta-gamma-delta 10089 2002.08.24 S16W05 plage 10090 2002.08.26 15 S04E07 0050 DSO 10091 2002.08.27 N06E11 plage 10092 2002.08.27 5 S19W22 0040 DSO 10093 2002.08.29 2 S16E13 0010 HRX now spotless 10094 2002.08.29 3 S17E67 0040 CSO beta-delta? 10095 2002.08.29 11 N07E76 0180 EAO beta-gamma-delta Total number of sunspots: 66 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 2001.07 131.3 81.8 111.7 (+1.9) 2001.08 162.9 106.4 113.6 (+1.8) 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 (114.0 predicted, -0.5) 2002.03 179.5 98.4 (110.3 predicted, -3.7) 2002.04 189.8 120.4 (104.5 predicted, -5.8) 2002.05 178.4 120.8 (100.0 predicted, -4.5) 2002.06 148.7 88.5 (95.5 predicted, -4.5) 2002.07 173.5 99.9 (90.6 predicted, -4.9) 2002.08 184.2 (1) 181.8 (2) (86.6 predicted, -4.0) 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 25-45% 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]