Solar Terrestrial Activity Report [Image] Last update February 13, 2002 at 05:00 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update February 2, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update February 2, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update February 2, 2002)] [Historical solar and geomagnetic data charts 1954-2001 (last update January 12, 2002)] Recent development The geomagnetic field was quiet to slightly unsettled on February 12. Solar wind speed ranged between 453 and 595 km/sec. Solar flare activity was low. Solar flux was 208.3, the planetary A index was 6 (3-hour K indices: 3221 1222, Boulder K indices: 3221 1222). Region 9809 rotated quietly off the visible disk. Region 9810 was quiet and stable and will rotate over the northwest limb on Feb.14. Region 9811 decayed slowly and was mostly quiet. Region 9821 simplified but could still produce occasional minor M class flares. Region 9822 decayed slowly and was quiet. Region 9823 was mostly unchanged and quiet. Region 9824 was quiet and stable. Region 9825 developed slowly and could produce M class flares. Region 9826 was quiet and stable. Region 9827 decayed into spotless plage. Region 9828 decayed slowly and appears to be spotless early on Feb.13. Flares and CMEs A total of 7 C class events were recorded on February 12. Region 9821 produced a C5.2 flare at 02:59 UTC. Region 9825 generated a C2.3 flare at 08:53, a C3.0 flare at 12:40 and a C5.8/1F long duration event peaking at 14:42 UTC. Region 9811 was the source of a C5.0 flare at 21:36 UTC. The background x-ray flux is at the class C1 level. Coronal holes What could be a small coronal hole in the southern hemisphere was in a geoeffective position on February 12. Forecast The geomagnetic field is expected to be quiet to unsettled on February 13-14. There is a possibility of a few unsettled to active intervals on February 15 as a coronal stream could reach the Earth. 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 no. Location at region numbered sunspots midnight Area Classification Comment 9807 2002.01.30 S27W86 plage 9809 2002.01.31 1 S06W91 0030 HSX 9810 2002.02.01 1 N10W68 0070 HSX 9811 2002.02.02 4 S26W45 0040 CSO 9815 2002.02.03 N11W50 plage 9817 2002.02.05 S06W71 plage 9818 2002.02.05 N06W38 plage 9819 2002.02.05 S30W19 plage 9820 2002.02.07 N14W25 plage 9821 2002.02.08 30 S13W38 0350 EKI 9822 2002.02.08 4 N18E12 0030 CSO 9823 2002.02.09 4 S04W19 0120 CAO 9824 2002.02.09 1 N22E30 0140 HAX 9825 2002.02.09 30 N13E30 0310 EKI beta-gamma 9826 2002.02.10 6 S22E12 0030 CSO 9827 2002.02.11 S25W56 plage 9828 2002.02.11 1 S16E38 0010 AXX Total number of sunspots: 86 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 2000.12 173.6 104.4 112.0 (-0.7) 2001.01 166.6 95.6 108.7 (-3.3) 2001.02 146.6 80.6 104.1 (-4.6) 2001.03 177.7 113.5 104.8 (+0.7) 2001.04 177.7 107.7 107.6 (+2.8) 2001.05 147.1 96.6 108.7 (+1.1) 2001.06 173.0 134.0 109.8 (+1.1) 2001.07 131.3 82.2 111.7 (+1.9) 2001.08 162.9 106.8 (113.5 predicted, +1.8) 2001.09 233.2 150.7 (113.3 predicted, -0.2) 2001.10 207.6 125.6 (111.0 predicted, -2.3) 2001.11 210.6 106.5 (109.6 predicted, -1.4) 2001.12 235.1 131.8 (106.2 predicted, -3.4) 2002.01 226.6 113.9 (102.6 predicted, -3.6) 2002.02 215.5 (1) 98.6 (2) (101.2 predicted, -1.4) 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 25-40% 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]