Solar Terrestrial Activity Report [Image] Last update June 10, 2000 at 04:20 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update June 2, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update June 2, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update June 2, 2000)] [Historical solar and geomagnetic data charts 1954-2000 (last update April 12, 2000)] Recent development The geomagnetic field was quiet to unsettled on June 9. Solar wind speed ranged between 570 and 751 km/sec. The CME associated with the X1 flare on June 7 arrived late in the day. The actual time of arrival is difficult to pinpoint as there was no solar wind shock, anyway, just after midnight solar wind speed increased from 520 to 680 km/sec. Solar wind speed was back to 520 km/sec again by 03:30 UTC. The interplanetary magnetic field swung moderately southwards just before midnight and has since then remained southwards. Solar flare activity was low. Solar flux was 168.9, the planetary A index was 8 (3-hour K indices: 2222 3333, Boulder K indices: 1113 2322). Region 9026 decayed significantly and lost its magnetic delta. The region has only a minor chance of producing an M flare, C class flaring is more likely. Region 9028 was quiet and stable and will rotate off the visible disk late today. Region 9030 developed slowly and was quiet. Region 9032 was quiet and stable. Region 9033 developed slowly and could produce isolated M class flares. Region 9034 was quiet and stable, as were regions 9035 and 9036. A fairly active region is approaching the northeast limb, it produced a couple of CMEs during the day. Flares and CMEs A total of 7 C class events were observed on June 9. Region 9026 produced a C2.2 flare at 20:48 UTC. The background x-ray flux is at the class B6 level. Coronal holes No obvious coronal holes are approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to active on June 10 with a chance of isolated minor storm intervals. Quiet to unsettled is expected for June 11-12. 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 9026 20000601 33 N22W29 0400 ESI 9028 20000601 4 N16W79 0050 CAO 9030 20000603 6 N12W24 0020 DSO 9032 20000605 8 S17W16 0020 CSO 9033 20000605 43 N22E28 0550 FKC beta-gamma 9034 20000606 1 S10E27 0080 HSX 9035 20000608 6 S17E01 0030 DAO 9036 20000608 2 S23E60 0170 HAX Total number of sunspots: 103 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.05 148.4 106.3 90.5 (+5.0) 1999.06 169.8 137.7 93.1 (+2.6) 1999.07 165.6 113.5 94.5 (+1.4) 1999.08 170.7 93.7 97.4 (+2.9) 1999.09 135.7 71.5 102.3 (+4.8) 1999.10 164.8 116.7 107.7 (+5.4) 1999.11 191.5 133.2 110.9 (+3.2) 1999.12 169.8 84.6 (111.2 predicted, +0.3) 2000.01 158.1 90.2 (112.4 predicted, +1.2) 2000.02 174.1 112.3 (115.8 predicted, +3.4) 2000.03 208.2 138.2 (119.6 predicted, +3.8) 2000.04 184.2 125.3 (121.7 predicted, +2.1) 2000.05 184.9 120.8 2000.06 172.4 (1) 43.8 (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]