Solar Terrestrial Activity Report [Image] Last update December 5, 2001 at 04:05 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update December 2, 2001)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update December 2, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update December 2, 2001)] [Historical solar and geomagnetic data charts 1954-2001 (last update October 16, 2001)] Recent development The geomagnetic field was quiet to slightly unsettled on December 4. Solar wind speed ranged between 441 and 561 km/sec under the influence of a fairly benign coronal stream. Solar flare activity was moderate. Solar flux was 233.3, the planetary A index was 6 (3-hour K indices: 3212 2222, Boulder K indices: 3212 2222). Region 9715 decayed slowly and quietly. Minor M class flares are possible. Region 9716 lost some of its spots and was otherwise mostly unchanged and quiet. Region 9717 decayed slowly and was quiet. Region 9718 developed slowly and has major flare potential. Region 9720 decayed slowly and quietly. Region 9721 was mostly unchanged and quiet. Region 9723 developed slowly and was quiet. Region 9724 was mostly quiet and stable, as were regions 9725 and 9726. Region 9727 is developing fairly quickly and could soon become capable of major flaring. New region 9728 emerged at a high northern latitude at the central meridian. Flares and CMEs A total of 5 C and 2 M class events were recorded on December 4. Region 9718 produced an M1.0 flare at 00:45, an M1.3 flare at 05:46, a C3.3 flare at 07:31, a C4.3 flare at 09:00 and a C1.9 flare at 22:02 UTC. Region 9725 generated a C3.8 flare at 01:25 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 December 5-7. 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 no. Location at region numbered sunspots midnight Area Classification Comment 9715 2001.11.23 16 N05W63 0550 DKO beta-gamma 9716 2001.11.25 11 S06W49 0080 DAO beta-gamma 9717 2001.11.27 6 N04W13 0170 EAO 9718 2001.11.27 27 S06W09 0660 EKI beta-gamma 9719 2001.11.28 N04W77 plage 9720 2001.11.28 6 S20W08 0040 ESO 9721 2001.11.28 3 N12E02 0200 CSO 9722 2001.12.01 S15W60 plage 9723 2001.12.01 5 S05E03 0040 DSO 9724 2001.12.01 3 N10E33 0050 CSO 9725 2001.12.02 6 S10W72 0050 DSO 9726 2001.12.02 4 S16E42 0060 CSO 9727 2001.12.03 4 S22E57 0220 CKO 9728 2001.12.04 3 N36W07 0020 DSO Total number of sunspots: 94 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 2000.10 167.4 99.4 114.5 (-1.8) 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 (108.5 predicted, -0.2) 2001.07 131.3 82.2 (108.1 predicted, -0.4) 2001.08 162.9 106.8 (108.7 predicted, +0.6) 2001.09 233.2 150.7 (108.1 predicted, -0.6) 2001.10 207.6 125.6 (105.3 predicted, -2.8) 2001.11 210.6 106.5 (103.7 predicted, -1.6) 2001.12 233.7 (1) 29.8 (2) (100.3 predicted, -3.4) 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]