Solar Terrestrial Activity Report [Image] Last update August 7, 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 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 unsettled to active on August 6. Solar wind speed ranged between 468 and 594 km/sec. Solar flare activity was low. Solar flux was 166.0, the planetary A index was 18 (3-hour K indices: 4433 3333, Boulder K indices: 4533 3322). Regions 9104, 9105, 9107 and 9110 were mostly quiet and stable. Region 9113 decayed and was quiet. Region 9114 was mostly unchanged and could produce C flares and perhaps a minor M flare. Region 9115 decayed slowly and could produce occasional C flares. Regions 9116 and 9117 were quiet and stable. Region 9118 decayed into spotless plage. Region 9119 developed slowly and could produce C flares. New region 9120 emerged in the southeast quadrant. New region 9121 emerged at a high latitude in the southeast quadrant. The region has so far developed at a moderate pace and could soon begin producing C flares. Flares and CMEs A total of 4 C class events were recorded on August 6. Region 9114 produced a C2.1 flare at 15:45 and a C1.1 flare at 17:49 UTC. Region 9107 generated a C1.7 flare at 18:49 UTC. The background x-ray flux is at the class B6 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to unsettled on August 7-8 with a chance of isolated active intervals. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is 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 9104 20000726 1 S19W67 0040 HSX 9105 20000727 1 N18W52 0050 HSX 9107 20000729 3 S16W41 0020 CAO 9109 20000729 S06W64 plage 9110 20000731 9 S18W19 0050 DSO 9111 20000801 N10W42 plage 9112 20000802 N14W66 plage 9113 20000802 2 S25W65 0010 BXO 9114 20000802 14 N12E28 0250 EAO 9115 20000803 5 N17E43 0170 DAO 9116 20000804 2 S13E37 0050 HSX 9117 20000805 1 S10W23 0020 HAX 9118 20000805 N18W15 plage 9119 20000805 7 S12W06 0040 CRO 9120 20000806 4 S22E24 0020 HSX 9121 20000806 5 S35E27 0070 CSO Total number of sunspots: 54 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 2000.08 155.5 (1) 28.9 (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]