Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update January 3, 2000 at 03:35 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 active on January 2. Solar wind speed ranged between 632 and 730 km/sec under the influence of a high speed coronal stream. Solar flare activity was low. Solar flux was 132.9, the planetary A index was 14 (3-hour Kp indices: 3334 3333, Boulder K indices: 2344 2332). Region 8810 decayed further and was quiet. Region 8813 developed quickly towards the end of the day and early on Jan.3. The region could soon become capable of minor M class flaring. Region 8814 was quiet and stable. Region 8815 developed several new spots late in the day. This development continues early on Jan.3 and the region is likely to produce C flares. Isolated minor M class flares will become possible should the current rate of development continue. Flares and CMEs Only 1 C flare was recorded on January 2. Region 8813 produced a C5.1 flare at 22:27 UTC. A filament erupted near the central meridian in the southern hemisphere (southwest of region 8813). As LASCO images are not available it is unknown if the eruption produced a possibly geoeffective coronal mass ejection. The background x-ray flux is at the class B3 level. Coronal holes A large trans equatorial coronal hole was in a geoeffective position on December 28 - January 1. Forecast The geomagnetic field is expected to be quiet to active on January 3-4 with a chance of isolated minor storm intervals. Low frequency (below 2 MHz) radio wave propagation along east-west paths over high and upper middle latitudes is generally poor to 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 8809 19991224 N24W46 plage 8810 19991224 7 N38W29 0180 EAO 8812 19991229 S27W73 plage 8813 19991229 7 S16E08 0060 DAO 8814 19991229 3 N10E21 0150 HAX 8815 19991231 12 N08E35 0070 CAO Total number of sunspots: 29 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 2000.01 131.4 (1) 4.5 (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]