Solar Terrestrial Activity Report [Image] Last update June 18, 2002 at 04:00 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update June 2, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update June 2, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update June 2, 2002)] [Historical solar and geomagnetic data charts 1954-2002 (last update April 13, 2002)] Recent development The geomagnetic field was quiet to unsettled on June 17. Solar wind speed ranged between 326 and 365 km/sec. Solar flare activity was low. Solar flux was 142.9, the planetary A index was 7 (3-hour K indices: 2212 2322, Boulder K indices: 2221 2211). Region 9991 was mostly quiet and stable. Region 9992 developed slowly and quietly. Region 9997 was quiet and stable. Region 10000 developed slowly and has many small spots early on June 18. Region 10001 lost some of its trailing spots and was otherwise mostly unchanged and quiet. Region 10003 decayed slowly and had a single tiny spot left at the end of the day, the region could become spotless later today. Region 10004 decayed early in the day, then began to develop slowly and has many small spots early on June 18. Region 10005 was quiet and stable. Flares and CMEs A total of 2 C class events were recorded on June 17. Region 9991 produced a C1.4 flare at 20:16 UTC. The background x-ray flux is at the class B4 level. Coronal holes A recurrent trans equatorial coronal hole was in a geoeffective position on June 16 and could cause a minor geomagnetic disturbance on June 19. Forecast The geomagnetic field is expected to be quiet to unsettled on June 18 and quiet to active on June 19-20. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is fair. 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 no. Location at region numbered sunspots midnight Area Classification Comment 9991 2002.06.07 2 S22W61 0330 CKO 9992 2002.06.08 3 S18W45 0010 BXO 9994 2002.06.09 N10W45 plage 9996 2002.06.12 S28W17 plage 9997 2002.06.12 3 N10E05 0010 BXO 10000 2002.06.14 9 N18E12 0030 CSO 10001 2002.06.14 8 N20E33 0190 DSO 10002 2002.06.15 S24W34 plage 10003 2002.06.15 1 S02E35 0000 AXX 10004 2002.06.15 9 S15W20 0020 CSO 10005 2002.06.16 1 N13E62 0120 HSX Total number of sunspots: 36 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 2001.05 147.1 96.6 108.6 (+1.1) 2001.06 173.0 134.0 109.8 (+1.2) 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 (115.1 predicted, -0.4) 2002.01 226.6 114.1 (113.8 predicted, -1.3) 2002.02 205.0 107.4 (112.9 predicted, -0.9) 2002.03 179.5 98.4 (108.4 predicted, -4.5) 2002.04 189.8 120.4 (102.5 predicted, -5.9) 2002.05 178.4 120.8 (98.1 predicted, -4.4) 2002.06 152.9 (1) 94.0 (2) (93.5 predicted, -4.6) 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]