Solar Terrestrial Activity Report [Image] Last update June 12, 2000 at 04:40 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 unsettled to major storm on June 11. Solar wind speed ranged between 453 and 579 km/sec. A solar wind shock was observed at 07:12 UTC at ACE. From then on and until approximately 16h UTC the interplanetary magnetic field was moderately to strongly southwards. Solar flare activity was moderate. Solar flux was 186.8, the planetary A index was 32 (3-hour K indices: 3336 5553, Boulder K indices: 3434 4452). Region 9026 decayed further and was quiet. Occasional C class flares are possible. Region 9030 developed early in the day, then produced a C7 flare and began to decay. Region 9032 decayed and was quiet, the region is spotless early on June 12. Region 9033 is fairly complex and could produce further M class flares. Region 9034 was quiet and stable, as was region 9035. Region 9036 developed slowly and could generate a minor M flare. Region 9037 is developing quickly and could become capable of M class flaring today. New region 9038 emerged in the northwest quadrant and is developing quickly. C class flares are possible, as is a minor M class flare should the current rate of development continue. New region 9039 emerged near the central meridian in the northwest quadrant. This region is exhibiting fairly strong growth as well and could produce C flares as well as a minor M flare should development continue. New region 9040 rotated partly into view at the northeast limb. New region 9041 emerged just to the north of region 9039 and has developed quickly. C class flares are likely. Flares and CMEs A total of 6 C class flares and 1 M flare were observed on June 11. Region 9030 produced a C3.8 flare at 03:04 and a C7.2/1F flare at 12:52 UTC. Region 9036 generated a C2.4 flare at 09:49 UTC. Region 9033 was the source of an M1.0/1F flare at 10:49 and a C2.9 flare at 18:18 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 June 12. The arrival of a CME on June 13 could cause unsettled to major storm conditions. 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 8 N21W52 0190 DSO 9030 20000603 10 N12W51 0020 CRO 9032 20000605 1 S17W37 0000 AXX 9033 20000605 43 N22E01 0540 FKO beta-gamma 9034 20000606 2 S10E01 0120 HSX 9035 20000608 3 S16W25 0010 CRO 9036 20000608 11 S23E40 0280 EAO beta-gamma 9037 20000610 8 N19E36 0100 DSO beta-gamma 9038 20000611 5 N15W29 0030 CAO 9039 20000611 4 N07W10 0040 DSO 9040 20000611 1 N19E73 0090 HSX 9041 20000611 8 N17W11 0020 BXO Total number of sunspots: 104 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 2000.06 174.4 (1) 56.8 (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]