Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update January 29, 2000 at 03:40 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 28. Solar wind speed ranged between 608 and 740 km/sec under the influence of a high speed coronal stream. Solar flare activity was low. Solar flux was 126.0, the planetary A index was 29 (3-hour Kp indices: 4544 5334, Boulder K indices: 3644 5434). Region 8841 was mostly unchanged and could produce further C flares. Region 8842 decayed into spotless plage, as did region 8840. Region 8844 did not change significantly and remains capable of C class flaring. The region will rotate over the west limb on January 30. Region 8845 was quiet and stable, as was region 8846. Region 8848 could produce further C flares. New region 8849 emerged in the southeast quadrant. Flares and CMEs 2 C flares were recorded on January 28. Region 8848 produced a C1.1 flare at 06:59 UTC. Region 8841 generated a long duration C4.7 flare peaking at 20:09 UTC. The background x-ray flux is at the class B4 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 unsettled to active on January 29 with a chance of isolated minor storm intervals. Quiet to active is likely for 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 N12W67 plage 8840 20000121 S24W76 plage 8841 20000121 8 S30W22 0180 CAO 8842 20000123 S16W79 plage 8843 20000123 N14W53 plage 8844 20000124 13 N05W73 0280 EAI 8845 20000125 4 S16W20 0030 CSO 8846 20000126 3 N37E25 0000 BXO 8847 20000126 S26W54 plage 8848 20000126 5 S09E54 0080 CAO 8849 20000128 3 S16E19 0010 BXO Total number of sunspots: 36 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 2000.01 160.8 (1) 132.7 (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]