Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update January 6, 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 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 predominantly unsettled on January 5 with a single active interval at the end of the day. Solar wind speed ranged between 491 and 568 km/sec still under the influence of a high speed coronal stream. Solar flare activity was low. Solar flux was 136.5, the planetary A index was 15 (3-hour Kp indices: 3333 3334, Boulder K indices: 3323 3333). Region 8810 was quiet and stable. Region 8813 decayed slowly and was quiet. Region 8814 was quiet and stable. Region 8815 decayed quickly and lost most of its spots. Region 8816 was quiet and stable, the region has developed fairly quickly early on Jan.6 and should be capable of C class flaring. Region 8817 was quiet and stable. New region 8818 emerged in the southwest quadrant. An active region is rotating onto the disk at the southeast limb. Flares and CMEs 3 C flares were recorded on January 5, none of which were optically correlated. A C2.4 flare was observed at 01:36 UTC and a C1.0 flare at 04:15 UTC. A long duration C1.7 event peaked at 22:00 UTC. There was no obvious event on the visible disk in LASCO EIT images, the source may have been behind the southeast limb. The background x-ray flux is at the class B3 level. Coronal holes A trans equatorial coronal hole will rotate into a geoeffective position on January 6-7. Forecast The geomagnetic field is expected to be quiet to unsettled on January 6-8. Low frequency (below 2 MHz) radio wave propagation along east-west paths over high and upper middle latitudes is generally 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 8809 19991224 N24W85 plage 8810 19991224 3 N38W65 0140 ESO 8813 19991229 6 S15W32 0120 DSO 8814 19991229 5 N11W19 0090 CSO 8815 19991231 3 N11W02 0010 HRX 8816 20000104 4 N23W29 0010 BXO 8817 20000104 7 N25W03 0030 CSO 8818 20000105 2 S10W33 0010 BXO Total number of sunspots: 30 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 2000.01 133.4 (1) 13.5 (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]