Solar Terrestrial Activity Report [Image] Last update March 16, 2000 at 02:50 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update 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 on March 15. Solar wind speed ranged between 277 and 338 km/sec. Solar flare activity was moderate. Solar flux was 177.8, the planetary A index was 3 (3-hour K indices: 1000 1211, Boulder K indices: 1010 1100). Region 8898 rotated off the visible disk. Regions 8901 and 8903 were mostly quiet and stable, region 8903 will rotate over the west limb today. Region 8902 decayed into spotless plage. Region 8906 developed a second magnetic delta (penumbra containing opposite polarity umbra) could produce a major flare any time. Region 8908 decayed into spotless plage. Region 8909 was quiet and stable. Region 8910 was mostly unchanged and has minor M class flaring potential. Region 8911 was quiet and stable. Region 8912 decayed into spotless plage. Region 8913 was quiet and stable. Several active regions are approaching the east limb. Flares and CMEs 14 C flares and 1 M flare were recorded on March 15. Region 8901 produced a C1.7 flare at 14:14 UTC. Region 8906 was the source of an impulsive M1.4/1N flare at 18:39 UTC. Minor filament eruptions were observed in both the southwest and southeast quadrants. The background x-ray flux is at the class B7 level. Coronal holes No obvious coronal holes are approaching geoeffective positions. Forecast The geomagnetic field is expected to be mostly quiet on March 16-17. 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 Location region numbered no. at Area Classification Comment sunspots midnight 8898 20000302 1 S12W89 0020 AXX 8901 20000305 4 S14W60 0020 BXO 8902 20000306 S17W43 plage 8903 20000307 1 S12W85 0020 HSX 8905 20000308 S06W70 plage 8906 20000308 47 S16W20 0720 EKC beta-gamma-delta 8907 20000308 S17W74 plage 8908 20000309 S23W05 plage 8909 20000311 3 S28E27 0020 BXO 8910 20000312 23 N11E31 0250 DAO beta-gamma-delta 8911 20000314 3 N12W55 0010 BXO 8912 20000314 N15W15 plage 8913 20000314 5 S16E57 0030 BXO Total number of sunspots: 87 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 2000.03 206.2 (1) 92.5 (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]