Solar Terrestrial Activity Report [Image] Last update January 28, 2002 at 04:25 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update January 1, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update January 1, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update January 1, 2002)] [Historical solar and geomagnetic data charts 1954-2001 (last update January 12, 2002)] Recent development The geomagnetic field was quiet to unsettled on January 27. Solar wind speed ranged between 318 and 417 km/sec. Solar flare activity was low. Solar flux was 248.0, the planetary A index was 7 (3-hour K indices: 3312 2222, Boulder K indices: 3322 2222). Region 9787 was quiet and stable. The huge main penumbra appears to be splitting into two. Minor M class flaring is still possible. Region 9788 was mostly quiet and stable, the region will rotate off the visible disk on January 29. Region 9793 decayed and was spotless by the end of the day. Region 9794 decayed slowly and quietly. Region 9798 was quiet and stable. Region 9799 decayed slowly and was quiet. Region 9800 developed quickly early in the day, then the positive and negative polarity areas began to drift apart slowly. The region is now magnetically simple and is likely to decay. Region 9801 was quiet and stable. Region 9802 developed slowly in the trailing section, but overall the area with tighter magnetic gradients weakened. There remains a possibility of minor M class flaring. New region 9803 emerged in the southwest quadrant. Flares and CMEs Only 1 C class event was recorded on January 27. Region 9787 produced a C2.7 flare at 17:23 UTC. The background x-ray flux is at the class C1 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to unsettled on January 28-30. 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 region numbered sunspots at Area Classification Comment midnight 9787 2002.01.17 5 S08W48 0450 CKO 9788 2002.01.18 12 N17W70 0120 DAO 9790 2002.01.19 N27W82 plage 9792 2002.01.20 N03W68 plage 9793 2002.01.20 3 S14W66 0010 BXO now spotless 9794 2002.01.20 5 N13W30 0040 CSO 9796 2002.01.23 N09W34 plage 9797 2002.01.23 S18W25 plage 9798 2002.01.23 5 S02W13 0020 CRO 9799 2002.01.23 7 S24E03 0100 DAO 9800 2002.01.25 35 N07E35 0330 EAI 9801 2002.01.25 3 S03E50 0110 DAO 9802 2002.01.26 10 S15E60 0230 DSO 9803 2002.01.27 4 S24W47 0030 CSO Total number of sunspots: 89 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 2000.11 178.8 106.8 112.7 (-1.8) 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 (111.2 predicted, +1.4) 2001.08 162.9 106.8 (111.7 predicted, +0.5) 2001.09 233.2 150.7 (110.7 predicted, -1.0) 2001.10 207.6 125.6 (108.0 predicted, -2.7) 2001.11 210.6 106.5 (106.3 predicted, -1.7) 2001.12 235.1 131.8 (103.0 predicted, -3.3) 2002.01 222.3 (1) 160.1 (2) (99.4 predicted, -3.6) 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 25-40% 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]