Solar Terrestrial Activity Report [Image] Last update December 9, 2001 at 04:10 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 on December 8. Solar wind speed ranged between 403 and 481 km/sec. Solar flare activity was moderate. Solar flux was 220.5, the planetary A index was 5 (3-hour K indices: 2022 2222, Boulder K indices: 2122 3111). Region 9717 was quiet and stable and will rotate off the visible disk early on Dec.10. Region 9718 was mostly quiet and stable but could still produce occasional minor M class flares. Region 9720 was quiet and stable as were regions 9721, 9723, 9724 and 9726. Region 9727 was mostly unchanged and remains capable of producing M class flares. Region 9728 decayed slowly and was quiet. Regions 9731 and 9732 were quiet and stable. New region 9733 rotated into view at the northeast limb. Further M class flares are possible. Flares and CMEs A total of 5 C and 1 M class events were recorded on December 8. Region 9733 was the source of a C5.3 flare at 02:24, a long duration M3.4 event peaking at 06:34 and a C4.5 flare at 11:14 UTC. Region 9718 generated a C2.9 flare at 04:32. Region 9727 produced a C4.2/1F flare at 21:43 and a C5.3 flare at 22:21 UTC. The background x-ray flux is at the class C1 level. Coronal holes An extension of a large southern hemisphere coronal hole will rotate into a geoeffective position on December 11. Forecast The geomagnetic field is expected to be quiet to unsettled on December 9-11. There is a minor chance of a weak CME impact on December 10. 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 9717 2001.11.27 1 N05W74 0100 HSX 9718 2001.11.27 15 S06W63 0470 DKI 9720 2001.11.28 10 S27W52 0050 DAO 9721 2001.11.28 4 N11W52 0100 DAO 9723 2001.12.01 3 S04W54 0040 DSO 9724 2001.12.01 5 N10W20 0040 CSO 9726 2001.12.02 8 S17W09 0060 DSO 9727 2001.12.03 21 S22E03 0370 DKI beta-gamma-delta 9728 2001.12.04 4 N36W60 0070 ESO 9729 2001.12.05 N23W35 plage 9730 2001.12.05 S12E08 plage 9731 2001.12.06 3 N24E09 0020 CRO 9732 2001.12.07 5 N04E52 0080 DSO 9733 2001.12.08 19 N14E67 0240 EAO beta-gamma Total number of sunspots: 98 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) 2001.12 233.1 (1) 58.9 (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]