Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update January 22, 2000 at 02:45 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 quiet on January 21. Solar wind speed ranged between 337 and 411 km/sec. A weak solar wind shock was observed at 00:25 UTC on January 22. Solar wind speed increased abruptly from 330 to 360 km/sec. Solar flare activity was moderate. Solar flux was 159.1, the planetary A index was 3 (3-hour Kp indices: 1000 1111, Boulder K indices: 1000 1112). Region 8824 rotated off the visible disk. Region 8829 was quiet and stable. Region 8831 decayed slowly and was quiet. Region 8833 was mostly unchanged and could generate C flares. Region 8836 reemerged with a couple of spots. Region 8837 developed further and has M class flaring potential. Region 8838 was mostly quiet and stable. Region 8839 developed slowly and could produce C flares. New region 8840 emerged in the southeast quadrant. New region 8841 rotated into view at the southeast limb. Flares and CMEs 5 C flares and 1 M flare were recorded on January 21. Region 8837 produced a C5.8 flare at 01:41 UTC, a C3.5 flare at 08:45 UTC and a C5.1 flare at 11:42 UTC. Region 8838 generated a C6.7 flare at 05:10 UTC. Region 8833 was the source of an M1.4 flare at 06:48 UTC. A filament erupted over the central meridian in the southern hemisphere starting at 10:12 UTC. The eruption was fairly slow and probably did not result in a significant CME. January 18: Region 8831 was the source of a long duration M3.9/1N event peaking at 17:27 UTC. This flare was associated with moderately strong type II and IV sweeps and a full halo coronal mass ejection. The CME will likely impact Earth sometime on January 21 or 22 and cause unsettled to major storm conditions. The background x-ray flux is at the class B5 level. Coronal holes A large trans equatorial coronal hole is rotating around the east limb. The southern part could rotate into a geoeffective position on January 25 and start a geomagnetic disturbance on January 28. Forecast The geomagnetic field is expected to be quiet to minor storm on January 22 as the CME observed on Jan.18 is likely to impact Earth today. Low frequency (below 2 MHz) radio wave propagation along east-west paths over high and upper middle latitudes is generally fair. 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 8825 20000110 N11W82 plage 8828 20000111 S23W73 plage 8829 20000111 2 N16W59 0060 HSX 8831 20000112 11 S18W38 0180 EAO 8833 20000113 6 N18W24 0180 CSO 8835 20000115 N08W24 plage 8836 20000116 2 S13W15 0000 AXX 8837 20000118 6 S07W69 0580 EKO 8838 20000118 9 N13E27 0050 DAO 8839 20000120 11 N12W07 0060 DAO 8840 20000121 4 S24E22 0000 BXO 8841 20000121 3 S28E70 0030 CAO Total number of sunspots: 54 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 2000.01 168.3 (1) 103.9 (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]