Solar Terrestrial Activity Report [Image] Last update September 16, 2002 at 03:55 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 3, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update September 3, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update September 3, 2002)] [Historical solar and geomagnetic data charts 1954-2002 (last update August 16, 2002)] Recent development The geomagnetic field was quiet to unsettled on September 15. Solar wind speed ranged between 343 and 382 km/sec. Solar flare activity was moderate. Solar flux was 187.8, the planetary A index was 8 (3-hour planetary K indices: 2233 2232, Boulder K indices: 1132 2222). Region 10103 decayed further as it began rotating over the northwest limb. Region 10105 decayed slightly and lost some its smaller spots. The region has become more active over the last day and could produce further M class flares. Region 10107 decayed and appears to be losing all its trailing spots. Region 10110 reemerged with a few spots, then began to decay slowly again. Region 10114 decayed slowly losing penumbral area in all parts of the region. M class flares are still possible. Region 10115 developed slowly as the negative and positive polarity drifted apart. New region 10116 emerged in the northeast quadrant. New region 10117 rotated into view at the southeast limb. Sometime after noon a new region emerged in the southeast quadrant and southeast of region 10115. Flares and CMEs A total of 10 C and 1 M class events was recorded on September 15. Region 10105 produced a C3.7 flare at 07:52 and an impulsive M1.0 flare at 17:38 UTC. Region 10114 generated a C3.1 flare at 15:38 and a C1.7 flare at 23:38 UTC. Region 10103 was the source of a C1.3 flare at 09:26 UTC. The background x-ray flux is at the class B7 level. Coronal holes No obvious coronal holes are currently rotating into geoeffective positions. Forecast The geomagnetic field is expected to be quiet to unsettled on September 16-18. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is fair to 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 only 4 small spots visible by 10103 2002.09.03 8 N16W84 0100 EAO early afternoon, area was 0030 then in a CAO classification 10104 2002.09.07 N09W49 plage 10105 2002.09.07 22 S07W31 0670 DKI beta-gamma 10106 2002.09.08 N27W42 plage 10107 2002.09.08 11 N11W23 0100 DAO 10108 2002.09.10 S24W19 plage 10109 2002.09.10 S08W49 plage 10110 2002.09.10 3 N19W48 0020 CRO 10111 2002.09.12 N11W38 plage 10112 2002.09.12 N00W35 plage 10113 2002.09.12 N30W77 plage 10114 2002.09.14 25 S12W15 0300 DAI beta-gamma 10115 2002.09.14 14 S03E32 0120 DSO 10116 2002.09.15 4 N15E05 0020 CSO 10117 2002.09.15 1 S09E72 0130 HSX Total number of sunspots: 88 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 2001.08 162.9 106.4 113.6 (+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) 2002.02 205.0 107.4 114.7 (+1.2) 2002.03 179.5 98.4 (113.2 predicted, -1.5) 2002.04 189.8 120.4 (108.7 predicted, -4.5) 2002.05 178.4 120.8 (104.2 predicted, -4.5) 2002.06 148.7 88.5 (99.7 predicted, -4.5) 2002.07 173.5 99.9 (94.9 predicted, -4.8) 2002.08 183.6 116.4 (90.8 predicted, -4.1) 2002.09 192.0 (1) 109.4 (2) (87.1 predicted, -3.7) 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]