Solar Terrestrial Activity Report [Image] Last update March 1, 2000 at 04:50 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update February 3, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update February 3, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update February 3, 2000)] [Historical solar and geomagnetic data charts 1954-1999] Recent development The geomagnetic field was quiet to unsettled on February 29. Solar wind speed ranged between 494 and 640 km/sec. A weak disturbance arrived shortly after 02h UTC on March 1. The interplanetary magnetic field strengthened and swung almost fully southwards. This could cause the geomagnetic field to become unsettled to active. Solar flare activity was low. Solar flux was 219.0, the planetary A index was 6 (3-hour K indices: 0133 2221, Boulder K indices: 1233 2221). Region 8879 will rotate over the west limb late today. Region 8881 was mostly quiet and stable. Region 8882 increased its areal coverage slowly and is still capable of producing a major flare. Region 8883 decayed slowly and was quiet. Region 8886 was quiet and stable. Region 8888 was quiet and stable. Region 8889 did not change significantly and was quiet, the region could produce a minor M flare. Region 8891 developed further and has major flare potential. Region 8892 was quiet and stable, as were regions 8893 and 8894 (region 8894 is rotating over the west limb). New region 8895 emerged in the northwest quadrant. New region 8896 rotated into view at the northeast limb. Flares and CMEs 9 C flares were recorded on February 29. Region 8879 produced a C6.9 flare at 15:23 UTC. Region 8882 was the source of the most significant flare of the day, a C9.4/1F flare at 17:08 UTC. Region 8891 generated a C3.0 flare at 15:05 UTC. The background x-ray flux is at the class B8 level. Coronal holes A small coronal hole in the northern hemisphere may have been in a geoeffective position on February 28. Forecast The geomagnetic field is expected to be quiet to active on March 1 and quiet to unsettled on March 2. 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 8879 20000217 1 N22W79 0180 HSX 8881 20000221 5 N19W58 0060 CSO 8882 20000221 18 S18W31 1080 EKI 8883 20000222 3 N12W36 0040 DSO 8886 20000223 5 S13W51 0070 DSO 8887 20000224 S11W17 plage 8888 20000224 3 N37W07 0040 CSO 8889 20000224 10 N21E06 0380 FSO 8890 20000224 S11W01 plage 8891 20000225 26 S16E21 1030 EKI beta-gamma 8892 20000226 2 N05E27 0010 CSO 8893 20000226 1 S19W67 0000 AXX 8894 20000228 1 S34W83 0010 AXX 8895 20000229 3 N13W48 0010 BXO 8896 20000229 3 N18E62 0050 DSO Total number of sunspots: 91 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.01 140.6 62.4 82.6 (+4.8) 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 (97.4 predicted, + 3.0) 1999.09 135.7 70.9 (102.4 predicted, +5.0) 1999.10 164.8 116.4 (107.5 predicted, +5.1) 1999.11 191.5 132.7 1999.12 169.8 86.4 2000.01 158.1 90.2 2000.02 174.1 (1) 161.4 (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 in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]