Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update January 12, 2000 at 05:00 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 quiet to minor storm on January 11. Solar wind speed ranged between 410 and 561 km/sec. A solar wind shock was observed at 13:40 UTC at ACE. The interplanetary magnetic field was at times strongly southwards following the shock and this again caused the geomagnetic field to become disturbed (in the unsettled to minor storm range). Solar flare activity was moderate. Solar flux was 177.6, the planetary A index was 16 (3-hour Kp indices: 2112 3454, Boulder K indices: 2212 3444). Region 8820 was quiet and stable. Region 8821 developed slowly and should be capable of C class flaring. Region 8822 decayed into spotless plage. Region 8823 was mostly unchanged and quiet. Region 8824 developed slowly and is likely to continue to produce C flares and minor M flares. There is a possibility of a major (proton) flare as well. Region 8825 was quiet and stable. New region 8826 emerged quickly in the northwest quadrant and is capable of C class flaring. New region 8827 emerged in the southwest quadrant. New region 8828 emerged near the southeast limb. New region 8829 rotated partly into view at the northeast limb. This region is bright and capable of M class flaring, major flares are possible as well. Flares and CMEs 8 C flares and 1 M flare were recorded on January 11. Region 8824 produced most of the flares with the most energetic ones being a C9.4 flare at 01:16 UTC and an M1.5 long duration event at 04:24 UTC. Region 8829 generated a C7.5 flare at 21:50 UTC. Early on January 12 two M flares have been observed. Region 8824 was the source of an M1.2/1F event at 00:17 UTC. A moderately strong type II sweep was noted around the same time but may have had its origin in an event in region 8815 at the west limb. Region 8829 produced an M2.8 flare at 01:38 UTC. The background x-ray flux is at the class C1 level. Coronal holes No obvious coronal holes are approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to active on January 12, quiet to unsettled is expected for January 13-14. 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 8815 19991231 N12W85 plage 8817 20000104 N24W84 plage 8820 20000106 4 S13E05 0020 DSO 8821 20000106 9 N28E15 0190 ESO 8822 20000107 N16W54 plage 8823 20000108 8 S33E26 0050 DSO 8824 20000109 21 S13E47 0250 EAI beta-gamma 8825 20000110 2 N11E45 0000 BXO 8826 20000111 6 N18W21 0030 DSO 8827 20000111 5 S11W20 0020 CSO 8828 20000111 1 S19E58 0000 AXX 8829 20000111 2 N16E78 0110 CAO Total number of sunspots: 58 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 2000.01 147.0 (1) 37.8 (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]