Solar Terrestrial Activity Report [Image] Last update January 31, 2002 at 04:30 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 on January 30. Solar wind speed ranged between 298 and 351 km/sec. Solar flare activity was low. Solar flux was 256.3, the planetary A index was 3 (3-hour K indices: 1010 1112, Boulder K indices: 0011 1122). Region 9787 rotated quietly over the southwest limb. Region 9799 decayed further and could become spotless today. Region 9800 decayed slowly and was mostly quiet. M class flares are possible. Region 9801 was quiet and stable. Region 9802 was mostly quiet despite having a magnetic delta structure. The delta weakened during the day. M class flares are possible. Region 9803 rotated quietly off the visible disk. Region 9805 decayed further and could become spotless today. Region 9806 was quiet and stable. New region 9807 rotated into view at the southeast limb. Another region, further north on the southeast limb, rotated partly into view but was not numbered by SEC/NOAA. Flares and CMEs A total of 7 C class events were recorded on January 30. Region 9802 produced a C3.6 flare at 02:40 UTC. The remaining C flares were all optically uncorrelated, however, a C7.4 flare at 16:39 UTC had its origin behind the northeast limb according to LASCO EIT images. The background x-ray flux is at the class C1 level. Coronal holes A coronal hole in the southern hemisphere will rotate into a geoeffective position on February 3. Forecast The geomagnetic field is expected to be quiet to unsettled on January 31-February 2. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is fair to good. 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 9787 2002.01.17 2 S07W89 0190 DSO 9794 2002.01.20 N14W72 plage 9796 2002.01.23 N09W73 plage 9797 2002.01.23 S18W64 plage 9798 2002.01.23 S02W52 plage 9799 2002.01.23 6 S23W35 0040 CSO 9800 2002.01.25 52 N08W03 0600 FKC beta-gamma 9801 2002.01.25 7 S04E12 0080 DSO 9802 2002.01.26 41 S17E22 0510 EAC beta-gamma-delta 9803 2002.01.27 2 S24W84 0040 CSO 9804 2002.01.28 S19E00 plage 9805 2002.01.28 4 N14E39 0010 CSO 9806 2002.01.28 1 N10E44 0040 HSX 9807 2002.01.30 5 S27E74 0160 ESO Total number of sunspots: 120 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) 2002.01 226.0 (1) 180.5 (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]