Solar Terrestrial Activity Report [Image] Last update December 4, 2000 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 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 to active on December 3. Solar wind speed ranged between 356 and 508 km/sec. A weak solar wind shock was observed at 03:20 UTC, this CME was probably related to the filament eruption observed near region 9247 on November 30. Solar wind speed increased abruptly from 380 to 420 km/sec and the interplanetary magnetic field swung moderately southwards. Solar flare activity was low. Solar flux was 163.6, the planetary A index was 12 (3-hour K indices: 1133 4431, Boulder K indices: 1243 3431). Region 9239 was quiet and stable, the region is rotating off the visible disk. Region 9240 was quiet and stable. Region 9242 did not change much and could produce C flares, a minor M class flare is a possibility. Region 9243 was quiet and stable, as was region 9245. Region 9246 decayed further and was quiet. Region 9247 decayed into spotless plage. Region 9248 developed slowly and was quiet. Region 9249 decayed into spotless plage. New region 9250 emerged near the southwest limb and will rotate out of view today. New regions 9251 and 9252 emerged in the southwest quadrant. New region 9253 emerged in the southeast quadrant. New regions 9254 and 9255 rotated into view at the northeast limb. Flares and CMEs A total of 3 C class events were recorded on December 3, none of the flare were optically assigned to any of the numbered regions. December 1: A filament near region 9243 erupted during the day. LASCO images were not available and it is difficult to know if a geoeffective CME was produced. A CME could reach Earth on December 4. The background x-ray flux is at the class B4 level. Coronal holes A 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 3 with a possibility of isolated active intervals. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is 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 9239 20001121 2 S21W82 0020 HSX 9240 20001122 1 N09W74 0140 HSX 9242 20001124 10 N20W54 0180 DSO 9243 20001127 6 S10W53 0030 DSO 9245 20001128 1 N04E00 0020 HSX 9246 20001128 17 S12W21 0130 EAO 9247 20001129 N14W33 plage 9248 20001130 5 N05W54 0020 DAO 9249 20001130 N12E04 plage 9250 20001203 1 S11W80 0000 AXX 9251 20001203 5 S22W34 0030 CSO 9252 20001203 4 S02W36 0020 CAO 9253 20001203 2 S14E11 0020 CSO 9254 20001203 1 N10E59 0010 HSX 9255 20001203 1 N21E64 0010 HSX Total number of sunspots: 56 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.10 164.8 116.7 107.8 (+5.5) 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) 2000.12 171.7 (1) 15.6 (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]