Solar Terrestrial Activity Report [Image] Last update March 4, 2000 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 March 2, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update March 2, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update March 2, 2000)] [Historical solar and geomagnetic data charts 1954-1999] Recent development The geomagnetic field was quiet to unsettled on March 3. Solar wind speed ranged between 382 and 441 km/sec. Solar flare activity was moderate. Solar flux was 203.8, the planetary A index was 5 (3-hour K indices: 1001 2322, Boulder K indices: 1001 2322). Region 8882 could produce M flares before departing the visible disk on March 5. Region 8883 was quiet and stable. Region 8886 was quite active and could produce further M flares while at or just behind the west limb today. Region 8888 decayed into spotless plage. Region 8889 decayed slowly and was mostly quiet. Region 8891 decayed slowly. Although the region still has major flare potential, there has been little activity of interest over the past couple of days. Region 8892 was quiet and stable. Region 8896 was quiet and stable, as were regions 8897 and 8898. New region 8899 emerged in the southeast quadrant. Flares and CMEs 6 C flares and 2 M flares were recorded on March 3. Region 8882 produced an impulsive M3.8/1B flare at 02:14 UTC. It was accompanied by a strong type IV sweep and a coronal mass ejection off the southwest limb. Region 8886 was the source of an impulsive M4.0 flare at 10:46 UTC and a C3.9 flare at 07:12 UTC. Region 8889 generated a C3.7 flare at 11:53 UTC. The most interesting event of the day occurred behind the southeast limb. A very large coronal mass ejection was observed starting in LASCO C2 images at 05:54 UTC. It is uncertain if the CME was associated with a flare or an erupting prominence. The CME was fairly wide and material streamed off the southeast limb for many hours following the start of the event. We will likely see one or two active regions rotating onto the disk at the southeast limb over the next 2-3 days. The background x-ray flux is at the class B9 level. Coronal holes A coronal hole in the northern hemisphere may be too far to the north to cause a geomagnetic disturbance when it rotates over the central meridian on March 6. Forecast The geomagnetic field is expected to be quiet to unsettled on March 4-5. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is poor and improving slowly. 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 8882 20000221 17 S16W71 0850 EKC beta-gamma 8883 20000222 2 N12W74 0020 HRX 8886 20000223 1 S12W87 0030 AXX 8887 20000224 S11W56 plage 8888 20000224 N37W40 plage 8889 20000224 10 N20W33 0190 FSO 8890 20000224 S11W40 plage 8891 20000225 33 S15W17 0830 EKC beta-gamma 8892 20000226 2 N06W12 0010 AXX 8895 20000229 N14W88 plage 8896 20000229 12 N19E26 0040 CSO 8897 20000301 5 S35W38 0030 CSO 8898 20000302 3 S16E60 0030 BXO 8899 20000303 4 S11E33 0010 BXO Total number of sunspots: 89 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.02 141.9 66.1 84.6 (+2.0) 1999.03 126.3 69.1 83.8 (-0.8) 1999.04 117.2 63.9 85.4 (+1.6) 1999.05 148.4 106.3 90.4 (+5.0) 1999.06 169.8 137.7 93.0 (+2.6) 1999.07 165.6 113.5 94.4 (+1.4) 1999.08 170.7 93.7 97.5 (+3.1) 1999.09 135.7 70.9 (102.6 predicted, +5.1) 1999.10 164.8 116.4 (107.7 predicted, +5.1) 1999.11 191.5 132.7 (110.2 predicted, +2.5) 1999.12 169.8 86.4 2000.01 158.1 90.2 2000.02 174.1 112.3 2000.03 216.6 (1) 19.9 (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 in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]