Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update January 30, 2000 at 03:00 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update January 1, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update January 1, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update January 1, 2000)] [Historical solar and geomagnetic data charts 1954-1999] [Experimental solar data chart January 1998-September 1999] Recent development The geomagnetic field was unsettled to minor storm on January 29. Solar wind speed ranged between 651 and 749 km/sec under the influence of a high speed coronal stream. Solar flare activity was very low. Solar flux was 127.7, the planetary A index was 25 (3-hour Kp indices: 3444 5443, Boulder K indices: 3444 4433). Region 8841 decayed slowly and was quiet. Region 8844 could produce isolated C flares while rotating over the west limb today. Region 8845 was quiet and stable. Region 8846 decayed into spotless plage. Region 8847 reemerged with a couple of spots and will rotate off the visible disk on January 31. Region 8848 was mostly quiet and stable and could produce occasional C flares. Region 8849 was quiet and stable. Active regions are approaching the east limb (both northeast and southeast limbs) and should rotate into view within 2-3 days. Flares and CMEs No flaring was observed on January 29. The background x-ray flux is at the class B2 level. Coronal holes A large trans equatorial coronal hole was in a geoeffective position on January 25-31. Forecast The geomagnetic field is expected to be quiet to active January 30 to February 3. Low frequency (below 2 MHz) radio wave propagation along east-west paths over high and upper middle latitudes is generally very 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 8838 20000118 N12W80 plage 8840 20000121 S24W89 plage 8841 20000121 3 S30W33 0130 CAO 8843 20000123 N14W66 plage 8844 20000124 3 N05W83 0200 DSO 8845 20000125 5 S17W33 0020 BXO 8846 20000126 N37E12 plage 8847 20000126 2 S26W71 0030 BXO 8848 20000126 6 S09E41 0100 CSO 8849 20000128 2 S17E07 0010 CRO Total number of sunspots: 21 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 (94.8 predicted, +1.8) 1999.08 170.7 93.7 (99.4 predicted, +4.6) 1999.09 135.7 70.6 (105.7 predicted, +6.3) 1999.10 164.8 116.4 1999.11 191.5 132.7 1999.12 169.8 86.4 2000.01 159.6 (1) 135.3 (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]