Solar Terrestrial Activity Report [Image] Last update December 6, 2000 at 05:20 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, 2000) - Has cycle 23 peaked?] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update December 2, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update December 2, 2000)] [Historical solar and geomagnetic data charts 1954-2000 (last update October 20, 2000)] Recent development The geomagnetic field was quiet on December 5. Solar wind speed ranged between 324 and 372 km/sec. Solar flare activity was low. Solar flux was 147.0, the planetary A index was 4 (3-hour K indices: 1111 2221, Boulder K indices: 1111 2200). Region 9242 was quiet and stable and is rotating over the west limb. Region 9243 decayed into spotless plage. Region 9245 was quiet and stable. Region 9246 was quiet and stable. Region 9248 decayed into spotless plage. Region 9254 is developing and could produce C and minor M class flares. Region 9255 was quiet and stable, as was region 9256. Flares and CMEs A total of 4 C class events were recorded on December 5. Spotless plage region 9248 produced a C2.2 flare at 04:47 while the other 3 events were optically uncorrelated. The background x-ray flux is at the class B4 level. Coronal holes A large trans equatorial coronal hole will rotate into a geoeffective position on December 6-9 and cause unsettled to major storm conditions on December 9-12. Forecast The geomagnetic field is expected to be quiet to unsettled on December 6-8. Quiet to minor storm is expected on December 9 due to a coronal stream. 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 9242 20001124 2 N19W81 0120 CAO 9243 20001127 S08W83 plage 9245 20001128 2 N04W25 0010 AXX 9246 20001128 13 S12W52 0100 CSO 9247 20001129 N14W59 plage 9248 20001130 N06W80 plage 9249 20001130 N12W22 plage 9251 20001203 S22W60 plage 9252 20001203 S02W62 plage 9253 20001203 S14W15 plage 9254 20001203 10 N10E36 0070 DAO 9255 20001203 1 N22E40 0010 AXX 9256 20001204 2 S17E51 0010 AXX Total number of sunspots: 30 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.11 191.5 133.2 111.0 (+3.2) 1999.12 169.8 84.6 111.1 (+0.1) 2000.01 158.1 90.1 112.9 (+1.8) 2000.02 174.1 112.9 116.7 (+3.8) 2000.03 208.2 138.5 119.9 (+3.2) 2000.04 184.2 125.5 120.8 (+0.9) 2000.05 184.9 121.6 119.0 (-1.8) 2000.06 179.8 124.9 (118.3 predicted, -0.7) 2000.07 202.3 169.1 (119.8 predicted, +1.5) 2000.08 163.0 130.5 (120.5 predicted, +0.7) 2000.09 182.1 109.9 (119.6 predicted, -0.9) 2000.10 167.4 100.1 (118.4 predicted, -1.2) 2000.11 178.8 106.5 (116.4 predicted, -2.0) 2000.12 162.8 (1) 22.4 (2) 1) Running average based on the daily 20:00 UTC solar flux value at 2800 MHz. 2) Unofficial, accumulated value. The official value 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] [StudyWeb]