Solar Terrestrial Activity Report [Image] Last update August 27, 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 minor storm on August 26. Solar wind speed ranged between 300 and 437 km/sec. Solar flare activity was moderate. Solar flux was 172.2, the planetary A index was 18 (3-hour planetary K indices: 3323 4533, Boulder K indices: 2223 4633). Region 10080 decayed slowly and rotated out of view at the northwest limb. Region 10083 decayed further losing about half its penumbral area. Region 10084 decayed slowly and quietly. Region 10085 decayed slightly and remains capable of producing occasional minor M class flares. Region 10087 developed slowly and could produce minor M class flares. Region 10088 decayed further and was quiet. New region 10090 was numbered as SEC/NOAA finally noticed this small region in the southeast quadrant. The region appears to be slowly decaying. Flares and CMEs A total of 7 C and 1 M class events was recorded on August 26. Region 10083 was the source of a long duration M1.8 event peaking at 01:00 UTC. A CME was observed mainly off the west limb, however, a faint halo could be observed all around the disk. A minor geomagnetic disturbance is possible on August 29. The region also produced a C7.6 flare at 16:24 and a C7.8 long duration event peaking at 20:11 UTC. Region 10085 generated a C2.9 flare at 05:37, a C4.0/1F flare at 09:45, a C2.5 flare at 13:00, a C3.4 flare at 18:42 and a C3.8 flare at 21:35 UTC. The background x-ray flux is at the class B7 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to active on August 27 and 29 and quiet to unsettled on August 28. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is poor to very 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 10080 2002.08.14 3 N12W83 0080 DAO area too large 10081 2002.08.16 N18W70 plage 10083 2002.08.17 2 S19W56 0090 HAX 10084 2002.08.18 3 S17W39 0050 CAO 10085 2002.08.19 12 S09W19 0500 DKO 10086 2002.08.22 S26W24 plage 10087 2002.08.22 9 S08E21 0390 DKO beta-gamma-delta 10088 2002.08.23 5 S23W68 0200 DAO 10089 2002.08.24 S16E34 plage 10090 2002.08.26 1 S03E48 0010 AXX Total number of sunspots: 35 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) 2002.08 186.5 (1) 170.0 (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]