Solar Terrestrial Activity Report [Image] Last update September 3, 2002 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 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 active on September 2. Solar wind speed ranged between 328 and 362 km/sec. Solar flare activity was low. Solar flux was 173.8, the planetary A index was 14 (3-hour planetary K indices: 3324 3332, Boulder K indices: 2324 3312). Region 10087 decayed moderately quickly and was quiet, the region will soon rotate over the southwest limb. Region 10090 decayed slowly and quietly. Region 10094 decayed slowly and appears to be losing the trailing spots. Region 10095 lost some of its smaller penumbra, particularly in the central and trailing spots section, however, both the main leading and trailing penumbrae increased their area. Currently the region is fairly simple magnetically with no polarity intermixing. A negative polarity area could be developing near the southern edge of the leading positive penumbra. Region 10096 was mostly unchanged and quiet. Region 10097 developed slowly and quietly. Region 10098 decayed and could soon become spotless. Region 10099 appears to be losing its trailing spots, the leading penumbra increased its areal coverage. Region 10100 was quiet and stable. Region 10101 was quiet and stable. New region 10102 rotated into view at the northeast limb. Early on September 3 there appears to be another region coming into view at the northeast limb. Flares and CMEs A total of 7 C class events was recorded on September 2. Region 10094 produced a C1.6 flare at 12:04 UTC, none of the other flares were optically correlated. 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 September 3 and quiet to unsettled on September 4-5. 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 area much too large, 10087 2002.08.22 5 S08W74 0180 CSO 0080 is a better estimate 10089 2002.08.24 S16W57 plage 10090 2002.08.26 4 S06W51 0030 CSO 10091 2002.08.27 N06W41 plage 10092 2002.08.27 S19W74 plage 10093 2002.08.29 S16W39 plage 10094 2002.08.29 8 S18E13 0160 DHO 10095 2002.08.29 53 N08E24 0840 FKI too many spots 10096 2002.08.30 10 S15E38 0170 DSO 10097 2002.08.31 19 N13E08 0110 DAI 10098 2002.08.31 2 S09E51 0030 CRO 10099 2002.09.01 8 S04E12 0070 DSO 10100 2002.09.01 6 S19E56 0210 DAO 10101 2002.09.01 1 N02E56 0040 HAX 10102 2002.09.02 1 N09E65 0050 HSX area too large, actually near 0030 Total number of sunspots: 117 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) 2002.09 177.2 (1) 13.8 (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]