Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update February 3, 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 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] [Experimental solar data chart January 1998-September 1999] Recent development The geomagnetic field was quiet to unsettled on February 2. Solar wind speed ranged between 438 and 494 km/sec. Solar flare activity was low. Solar flux was 144.4, the planetary A index was 7 (3-hour Kp indices: 3102 3321, Boulder K indices: 2202 3221). Regions 8841 and 8845 were quiet and stable, both rotated over the west limb early today. Region 8848 decayed slowly and was quiet. Region 8851 was quiet and stable. The region could produce occasional C flares. Region 8852 decayed and was quiet. Region 8853 was quiet and stable, as was region 8854. New region 8855 rotated into view at the northeast limb. New region 8856 (old region 8824) rotated partly into view at the southeast limb. Region 8856 probably has M class flaring potential. An active region at the northeast limb could be capable of M class flaring as well. Flares and CMEs 2 C flares were recorded on February 2. A region at the northeast limb produced a C4.4 long duration flare peaking at 22:38 UTC. The background x-ray flux is at the class B6 level. Coronal holes A trans equatorial coronal hole will likely rotate into a geoeffective position on February 2-4. Forecast The geomagnetic field is expected to be quiet to unsettled on February 3-5. Unsettled to active is likely on February 6-7 due to a coronal stream. Low frequency (below 2 MHz) radio wave propagation along east-west paths over high and upper middle latitudes is generally 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 8841 20000121 3 S32W85 0050 CSO 8845 20000125 1 S16W86 0030 HRX 8846 20000126 N37W40 plage 8848 20000126 3 S08W16 0070 CSO 8849 20000128 S17W45 plage 8850 20000130 S17W15 plage 8851 20000130 18 N26E03 0110 DSO 8852 20000131 5 N10W12 0010 BXO 8853 20000201 2 S10E52 0010 AXX 8854 20000201 1 S35E70 0080 HAX 8855 20000202 3 N15E57 0020 BXO 8856 20000202 1 S13E81 0040 HSX Total number of sunspots: 37 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1998.12 150.1 81.9 77.9 (+4.9) 1999.01 140.6 62.0 82.6 (+4.7) 1999.02 141.9 66.3 84.6 (+2.0) 1999.03 126.3 68.8 83.8 (-0.8) 1999.04 117.2 63.7 85.4 (+1.6) 1999.05 148.4 106.4 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 2000.02 141.3 (1) 8.1 (2) 1) Running average based on the daily 20:00 UTC solar flux measurement at 2800 MHz by DRAO. 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]