Solar Terrestrial Activity Report [Image] Last update August 9, 2000 at 04:15 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update August 4, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update August 4, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update August 4, 2000)] [Historical solar and geomagnetic data charts 1954-2000 (last update April 12, 2000)] Recent development The geomagnetic field was quiet to unsettled on August 8. Solar wind speed ranged between 366 and 461 km/sec. Solar flare activity was moderate. Solar flux was 170, the planetary A index was 9 (3-hour K indices: 2232 2232, Boulder K indices: 2231 2222). Regions 9105, 9107 and 9110 were quiet and stable, region 9105 is rotating off the visible disk. Region 9114 was quiet and stable. The region still has a weak magnetic delta configuration and could produce C flares and minor M class. Region 9115 was quiet and stable. Regions 9116 and 9117 both decayed slowly and could become spotless in a day or two. Region 9119 was quiet and mostly unchanged. Regions 9120 and 9121 were quiet and mostly stable. Region 9122 developed further and could produce C flares and perhaps a minor M class flare. New region 9123 rotated into view at the northeast limb. Very strong emissions are observed above the southeast limb as a hot, active region is beginning to rotate into view. Further M class flares can be expected from this region, a major flare is possible as well. Flares and CMEs A total of 3 C and 1 M class events were recorded on August 8. The region at the southeast limb produced a long duration M1.9 event peaking at 11:15 UTC. A filament eruption was observed in the southeast quadrant near regions 9120 and 9116 on August 7. The eruption started at 22:00 UTC and was followed by a coronal mass ejection which spanned most of the east limb. There is a small chance of a weak terrestrial impact on August 11. The background x-ray flux is at the class B7-B8 level. Coronal holes A coronal hole in the southern hemisphere will rotate into a geoeffective position on August 11-13 and could cause unsettled to active intervals on August 14-16. Forecast The geomagnetic field is expected to be quiet to unsettled on August 9-11. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is 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 Location region numbered no. at Area Classification Comment sunspots midnight 9105 20000727 1 N17W80 0060 HSX 9107 20000729 3 S13W75 0030 CRO 9110 20000731 5 S18W47 0040 DSO 9111 20000801 N10W68 plage 9114 20000802 21 N11W01 0290 EKI beta-gamma-delta 9115 20000803 5 N18E14 0170 CAO 9116 20000804 3 S12E14 0010 AXX 9117 20000805 1 S10W51 0000 AXX 9118 20000805 N18W41 plage 9119 20000805 7 S13W34 0050 CAO 9120 20000806 3 S21W04 0010 BXO 9121 20000806 3 S34E01 0100 DAO 9122 20000807 15 N22E35 0160 DAI beta-gamma 9123 20000808 1 N18E72 0080 HSX Total number of sunspots: 68 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.07 165.6 113.5 94.3 (+1.2) 1999.08 170.7 93.7 97.5 (+3.2) 1999.09 135.7 71.5 102.3 (+4.8) 1999.10 164.8 116.7 107.8 (+5.5) 1999.11 191.5 133.2 110.9 (+3.1) 1999.12 169.8 84.6 111.0 (+0.1) 2000.01 158.1 90.1 112.8 (+1.8) 2000.02 174.1 112.9 (117.0 predicted, +4.2) 2000.03 208.2 138.5 (120.7 predicted, +3.7) 2000.04 184.2 125.3 (122.9 predicted, +2.2) 2000.05 184.9 120.8 (123.7 predicted, +0.8) 2000.06 179.8 124.9 (125.3 predicted, +1.6) 2000.07 202.3 169.1 2000.08 158.8 (1) 41.1 (2) 1) Running average based on the daily 20:00 UTC solar flux value at 2800 MHz. 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]